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http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#Factor
Factor
USING: calendar formatting io kernel math.ranges sequences ;   : long-year? ( n -- ? ) 12 28 <date> week-number 53 = ;   "Year Long?\n-----------" print 1990 2021 [a,b] [ dup long-year? "yes" "no" ? "%d  %s\n" printf ] each
http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#Forth
Forth
: dec31wd ( year -- weekday ) dup dup 4 / swap dup 100 / swap 400 / swap - + + 7 mod ; : long? ( year -- flag ) dup dec31wd 4 = if drop 1 else 1 - dec31wd 3 = if 1 else 0 then then ; : demo ( startyear endyear -- ) cr swap do i long? if i . then loop cr ;
http://rosettacode.org/wiki/Long_primes
Long primes
A   long prime   (as defined here)   is a prime number whose reciprocal   (in decimal)   has a   period length   of one less than the prime number. Long primes   are also known as:   base ten cyclic numbers   full reptend primes   golden primes   long period primes   maximal period primes   proper primes Another definition:   primes   p   such that the decimal expansion of   1/p   has period   p-1,   which is the greatest period possible for any integer. Example 7   is the first long prime,   the reciprocal of seven is   1/7,   which is equal to the repeating decimal fraction   0.142857142857··· The length of the   repeating   part of the decimal fraction is six,   (the underlined part)   which is one less than the (decimal) prime number   7. Thus   7   is a long prime. There are other (more) general definitions of a   long prime   which include wording/verbiage for bases other than ten. Task   Show all long primes up to   500   (preferably on one line).   Show the   number   of long primes up to        500   Show the   number   of long primes up to     1,000   Show the   number   of long primes up to     2,000   Show the   number   of long primes up to     4,000   Show the   number   of long primes up to     8,000   Show the   number   of long primes up to   16,000   Show the   number   of long primes up to   32,000   Show the   number   of long primes up to   64,000   (optional)   Show all output here. Also see   Wikipedia: full reptend prime   MathWorld: full reptend prime   OEIS: A001913
#Factor
Factor
USING: formatting fry io kernel math math.functions math.primes math.primes.factors memoize prettyprint sequences ; IN: rosetta-code.long-primes   : period-length ( p -- len ) [ 1 - divisors ] [ '[ 10 swap _ ^mod 1 = ] ] bi find nip ;   MEMO: long-prime? ( p -- ? ) [ period-length ] [ 1 - ] bi = ;   : .lp<=500 ( -- ) 500 primes-upto [ long-prime? ] filter "Long primes <= 500:" print [ pprint bl ] each nl ;   : .#lp<=n ( n -- ) dup primes-upto [ long-prime? t = ] count swap "%-4d long primes <= %d\n" printf ;   : long-primes-demo ( -- ) .lp<=500 nl { 500 1,000 2,000 4,000 8,000 16,000 32,000 64,000 } [ .#lp<=n ] each ;   MAIN: long-primes-demo
http://rosettacode.org/wiki/Long_primes
Long primes
A   long prime   (as defined here)   is a prime number whose reciprocal   (in decimal)   has a   period length   of one less than the prime number. Long primes   are also known as:   base ten cyclic numbers   full reptend primes   golden primes   long period primes   maximal period primes   proper primes Another definition:   primes   p   such that the decimal expansion of   1/p   has period   p-1,   which is the greatest period possible for any integer. Example 7   is the first long prime,   the reciprocal of seven is   1/7,   which is equal to the repeating decimal fraction   0.142857142857··· The length of the   repeating   part of the decimal fraction is six,   (the underlined part)   which is one less than the (decimal) prime number   7. Thus   7   is a long prime. There are other (more) general definitions of a   long prime   which include wording/verbiage for bases other than ten. Task   Show all long primes up to   500   (preferably on one line).   Show the   number   of long primes up to        500   Show the   number   of long primes up to     1,000   Show the   number   of long primes up to     2,000   Show the   number   of long primes up to     4,000   Show the   number   of long primes up to     8,000   Show the   number   of long primes up to   16,000   Show the   number   of long primes up to   32,000   Show the   number   of long primes up to   64,000   (optional)   Show all output here. Also see   Wikipedia: full reptend prime   MathWorld: full reptend prime   OEIS: A001913
#Forth
Forth
: prime? ( n -- ? ) here + c@ 0= ; : notprime! ( n -- ) here + 1 swap c! ;   : sieve ( n -- ) here over erase 0 notprime! 1 notprime! 2 begin 2dup dup * > while dup prime? if 2dup dup * do i notprime! dup +loop then 1+ repeat 2drop ;   : modpow { c b a -- a^b mod c } c 1 = if 0 exit then 1 a c mod to a begin b 0> while b 1 and 1 = if a * c mod then a a * c mod to a b 2/ to b repeat ;   : divide_out ( n1 n2 -- n ) begin 2dup mod 0= while tuck / swap repeat drop ;   : long_prime? ( n -- ? ) dup prime? invert if drop false exit then 10 over mod 0= if drop false exit then dup 1- 2 >r begin over r@ dup * > while r@ prime? if dup r@ mod 0= if over dup 1- r@ / 10 modpow 1 = if 2drop rdrop false exit then r@ divide_out then then r> 1+ >r repeat rdrop dup 1 = if 2drop true exit then over 1- swap / 10 modpow 1 <> ;   : next_long_prime ( n -- n ) begin 2 + dup long_prime? until ;   500 constant limit1 512000 constant limit2   : main limit2 1+ sieve limit2 limit1 3 0 >r ." Long primes up to " over 1 .r ." :" cr begin 2 pick over > while next_long_prime dup limit1 < if dup . then dup 2 pick > if over limit1 = if cr then ." Number of long primes up to " over 6 .r ." : " r@ 5 .r cr swap 2* swap then r> 1+ >r repeat 2drop drop rdrop ;   main bye
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously
Loop over multiple arrays simultaneously
Task Loop over multiple arrays   (or lists or tuples or whatever they're called in your language)   and display the   i th   element of each. Use your language's   "for each"   loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: (a,b,c) (A,B,C) (1,2,3) to produce the output: aA1 bB2 cC3 If possible, also describe what happens when the arrays are of different lengths. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#BaCon
BaCon
  DECLARE a1$[] = {"a", "b", "c"} TYPE STRING DECLARE a2$[] = {"A", "B", "C"} TYPE STRING DECLARE a3[] = {1, 2, 3} TYPE int     WHILE (a3[i] <= 3) PRINT a1$[i], a2$[i], a3[i] INCR i WEND  
http://rosettacode.org/wiki/Loops/Break
Loops/Break
Task Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive). If a number is 10, stop the loop after printing it, and do not generate any further numbers. Otherwise, generate and print a second random number before restarting the loop. If the number 10 is never generated as the first number in a loop, loop forever. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges
#C.2B.2B
C++
#include <iostream> #include <ctime> #include <cstdlib>   int main(){ srand(time(NULL)); // randomize seed while(true){ const int a = rand() % 20; // biased towards lower numbers if RANDMAX % 20 > 0 std::cout << a << std::endl; if(a == 10) break; const int b = rand() % 20; std::cout << b << std::endl; } return 0; }
http://rosettacode.org/wiki/Longest_common_subsequence
Longest common subsequence
Introduction Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string. The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings. Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be strings drawn from an alphabet Σ of size s, containing every distinct symbol in A + B. An ordered pair (i, j) will be referred to as a match if A[i] = B[j], where 0 < i ≤ m and 0 < j ≤ n. Define a non-strict product-order (≤) over ordered pairs, such that (i1, j1) ≤ (i2, j2) ⇔ i1 ≤ i2 and j1 ≤ j2. We define (≥) similarly. We say m1, m2 are comparable if either m1 ≤ m2 or m1 ≥ m2 holds. If i1 < i2 and j2 < j1 (or i2 < i1 and j1 < j2) then neither m1 ≤ m2 nor m1 ≥ m2 are possible; and we say m1, m2 are incomparable. We also define the strict product-order (<) over ordered pairs, such that (i1, j1) < (i2, j2) ⇔ i1 < i2 and j1 < j2. We define (>) similarly. Given a set of matches M, a chain C is a subset of M consisting of at least one element m; and where either m1 < m2 or m1 > m2 for every pair of distinct elements m1 and m2. An antichain D is any subset of M in which every pair of distinct elements m1 and m2 are incomparable. The set M represents a relation over match pairs: M[i, j] ⇔ (i, j) ∈ M. A chain C can be visualized as a curve which strictly increases as it passes through each match pair in the m*n coordinate space. Finding an LCS can be restated as the problem of finding a chain of maximum cardinality p over the set of matches M. According to [Dilworth 1950], this cardinality p equals the minimum number of disjoint antichains into which M can be decomposed. Note that such a decomposition into the minimal number p of disjoint antichains may not be unique. Contours Forward Contours FC[k] of class k are defined inductively, as follows: FC[0] consists of those elements m1 for which there exists no element m2 such that m2 < m1. FC[k] consists of those elements m1 for which there exists no element m2 such that m2 < m1; and where neither m1 nor m2 are contained in FC[l] for any class l < k. Reverse Contours RC[k] of class k are defined similarly. Members of the Meet (∧), or Infimum of a Forward Contour are referred to as its Dominant Matches: those m1 for which there exists no m2 such that m2 < m1. Members of the Join (∨), or Supremum of a Reverse Contour are referred to as its Dominant Matches: those m1 for which there exists no m2 such that m2 > m1. Where multiple Dominant Matches exist within a Meet (or within a Join, respectively) the Dominant Matches will be incomparable to each other. Background Where the number of symbols appearing in matches is small relative to the length of the input strings, reuse of the symbols increases; and the number of matches will tend towards quadratic, O(m*n) growth. This occurs, for example, in the Bioinformatics application of nucleotide and protein sequencing. The divide-and-conquer approach of [Hirschberg 1975] limits the space required to O(n). However, this approach requires O(m*n) time even in the best case. This quadratic time dependency may become prohibitive, given very long input strings. Thus, heuristics are often favored over optimal Dynamic Programming solutions. In the application of comparing file revisions, records from the input files form a large symbol space; and the number of symbols approaches the length of the LCS. In this case the number of matches reduces to linear, O(n) growth. A binary search optimization due to [Hunt and Szymanski 1977] can be applied to the basic Dynamic Programming approach, resulting in an expected performance of O(n log m). Performance can degrade to O(m*n log m) time in the worst case, as the number of matches grows to O(m*n). Note [Rick 2000] describes a linear-space algorithm with a time bound of O(n*s + p*min(m, n - p)). Legend A, B are input strings of lengths m, n respectively p is the length of the LCS M is the set of match pairs (i, j) such that A[i] = B[j] r is the magnitude of M s is the magnitude of the alphabet Σ of distinct symbols in A + B References [Dilworth 1950] "A decomposition theorem for partially ordered sets" by Robert P. Dilworth, published January 1950, Annals of Mathematics [Volume 51, Number 1, pp. 161-166] [Goeman and Clausen 2002] "A New Practical Linear Space Algorithm for the Longest Common Subsequence Problem" by Heiko Goeman and Michael Clausen, published 2002, Kybernetika [Volume 38, Issue 1, pp. 45-66] [Hirschberg 1975] "A linear space algorithm for computing maximal common subsequences" by Daniel S. Hirschberg, published June 1975 Communications of the ACM [Volume 18, Number 6, pp. 341-343] [Hunt and McIlroy 1976] "An Algorithm for Differential File Comparison" by James W. Hunt and M. Douglas McIlroy, June 1976 Computing Science Technical Report, Bell Laboratories 41 [Hunt and Szymanski 1977] "A Fast Algorithm for Computing Longest Common Subsequences" by James W. Hunt and Thomas G. Szymanski, published May 1977 Communications of the ACM [Volume 20, Number 5, pp. 350-353] [Rick 2000] "Simple and fast linear space computation of longest common subsequences" by Claus Rick, received 17 March 2000, Information Processing Letters, Elsevier Science [Volume 75, pp. 275–281] Examples The sequences "1234" and "1224533324" have an LCS of "1234": 1234 1224533324 For a string example, consider the sequences "thisisatest" and "testing123testing". An LCS would be "tsitest": thisisatest testing123testing In this puzzle, your code only needs to deal with strings. Write a function which returns an LCS of two strings (case-sensitive). You don't need to show multiple LCS's. For more information on this problem please see Wikipedia. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#CoffeeScript
CoffeeScript
  lcs = (s1, s2) -> len1 = s1.length len2 = s2.length   # Create a virtual matrix that is (len1 + 1) by (len2 + 1), # where m[i][j] is the longest common string using only # the first i chars of s1 and first j chars of s2. The # matrix is virtual, because we only keep the last two rows # in memory. prior_row = ('' for i in [0..len2])   for i in [0...len1] row = [''] for j in [0...len2] if s1[i] == s2[j] row.push prior_row[j] + s1[i] else subs1 = row[j] subs2 = prior_row[j+1] if subs1.length > subs2.length row.push subs1 else row.push subs2 prior_row = row   row[len2]   s1 = "thisisatest" s2 = "testing123testing" console.log lcs(s1, s2)
http://rosettacode.org/wiki/Look-and-say_sequence
Look-and-say sequence
The   Look and say sequence   is a recursively defined sequence of numbers studied most notably by   John Conway. The   look-and-say sequence   is also known as the   Morris Number Sequence,   after cryptographer Robert Morris,   and the puzzle   What is the next number in the sequence 1,   11,   21,   1211,   111221?   is sometimes referred to as the Cuckoo's Egg,   from a description of Morris in Clifford Stoll's book   The Cuckoo's Egg. Sequence Definition Take a decimal number Look at the number, visually grouping consecutive runs of the same digit. Say the number, from left to right, group by group; as how many of that digit there are - followed by the digit grouped. This becomes the next number of the sequence. An example: Starting with the number 1,   you have one 1 which produces 11 Starting with 11,   you have two 1's.   I.E.:   21 Starting with 21,   you have one 2, then one 1.   I.E.:   (12)(11) which becomes 1211 Starting with 1211,   you have one 1, one 2, then two 1's.   I.E.:   (11)(12)(21) which becomes 111221 Task Write a program to generate successive members of the look-and-say sequence. Related tasks   Fours is the number of letters in the ...   Number names   Self-describing numbers   Self-referential sequence   Spelling of ordinal numbers See also   Look-and-Say Numbers (feat John Conway), A Numberphile Video.   This task is related to, and an application of, the Run-length encoding task.   Sequence A005150 on The On-Line Encyclopedia of Integer Sequences.
#BCPL
BCPL
get "libhdr"   manifest $( amount = 15 bufsize = 128 $)   let move(dest,src) be $( until !src = 0 do $(  !dest := !src dest := dest + 1 src := src + 1 $)  !dest := 0 $)   let count(v) = valof $( let i=1 while v!i = !v do i := i + 1 resultis i $)   let looksay(in,out) be $( until !in = 0 do $( let n = count(in) out!0 := n out!1 := !in out := out + 2 in := in + n $)  !out := 0 $)   let show(v) be $( until !v = 0 do $( writen(!v) v := v + 1 $) wrch('*N') $)   let start() be $( let buf1 = vec bufsize and buf2 = vec bufsize buf1!0 := 1 buf1!1 := 0 for n = 1 to amount do $( show(buf1) looksay(buf1,buf2) move(buf1,buf2) $) $)
http://rosettacode.org/wiki/Longest_string_challenge
Longest string challenge
Background This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the challenge and fun part came through the introduction of restrictions. Experience has shown that the original restrictions required some adjustment to bring out the intent of the challenge and make it suitable for Rosetta Code. Basic problem statement Write a program that reads lines from standard input and, upon end of file, writes the longest line to standard output. If there are ties for the longest line, the program writes out all the lines that tie. If there is no input, the program should produce no output. Task Implement a solution to the basic problem that adheres to the spirit of the restrictions (see below). Describe how you circumvented or got around these 'restrictions' and met the 'spirit' of the challenge. Your supporting description may need to describe any challenges to interpreting the restrictions and how you made this interpretation. You should state any assumptions, warnings, or other relevant points. The central idea here is to make the task a bit more interesting by thinking outside of the box and perhaps by showing off the capabilities of your language in a creative way. Because there is potential for considerable variation between solutions, the description is key to helping others see what you've done. This task is likely to encourage a variety of different types of solutions. They should be substantially different approaches. Given the input: a bb ccc ddd ee f ggg the output should be (possibly rearranged): ccc ddd ggg Original list of restrictions No comparison operators may be used. No arithmetic operations, such as addition and subtraction, may be used. The only datatypes you may use are integer and string. In particular, you may not use lists. Do not re-read the input file. Avoid using files as a replacement for lists (this restriction became apparent in the discussion). Intent of restrictions Because of the variety of languages on Rosetta Code and the wide variety of concepts used in them, there needs to be a bit of clarification and guidance here to get to the spirit of the challenge and the intent of the restrictions. The basic problem can be solved very conventionally, but that's boring and pedestrian. The original intent here wasn't to unduly frustrate people with interpreting the restrictions, it was to get people to think outside of their particular box and have a bit of fun doing it. The guiding principle here should be to be creative in demonstrating some of the capabilities of the programming language being used. If you need to bend the restrictions a bit, explain why and try to follow the intent. If you think you've implemented a 'cheat', call out the fragment yourself and ask readers if they can spot why. If you absolutely can't get around one of the restrictions, explain why in your description. Now having said that, the restrictions require some elaboration. In general, the restrictions are meant to avoid the explicit use of these features. "No comparison operators may be used" - At some level there must be some test that allows the solution to get at the length and determine if one string is longer. Comparison operators, in particular any less/greater comparison should be avoided. Representing the length of any string as a number should also be avoided. Various approaches allow for detecting the end of a string. Some of these involve implicitly using equal/not-equal; however, explicitly using equal/not-equal should be acceptable. "No arithmetic operations" - Again, at some level something may have to advance through the string. Often there are ways a language can do this implicitly advance a cursor or pointer without explicitly using a +, - , ++, --, add, subtract, etc. The datatype restrictions are amongst the most difficult to reinterpret. In the language of the original challenge strings are atomic datatypes and structured datatypes like lists are quite distinct and have many different operations that apply to them. This becomes a bit fuzzier with languages with a different programming paradigm. The intent would be to avoid using an easy structure to accumulate the longest strings and spit them out. There will be some natural reinterpretation here. To make this a bit more concrete, here are a couple of specific examples: In C, a string is an array of chars, so using a couple of arrays as strings is in the spirit while using a second array in a non-string like fashion would violate the intent. In APL or J, arrays are the core of the language so ruling them out is unfair. Meeting the spirit will come down to how they are used. Please keep in mind these are just examples and you may hit new territory finding a solution. There will be other cases like these. Explain your reasoning. You may want to open a discussion on the talk page as well. The added "No rereading" restriction is for practical reasons, re-reading stdin should be broken. I haven't outright banned the use of other files but I've discouraged them as it is basically another form of a list. Somewhere there may be a language that just sings when doing file manipulation and where that makes sense; however, for most there should be a way to accomplish without resorting to an externality. At the end of the day for the implementer this should be a bit of fun. As an implementer you represent the expertise in your language, the reader may have no knowledge of your language. For the reader it should give them insight into how people think outside the box in other languages. Comments, especially for non-obvious (to the reader) bits will be extremely helpful. While the implementations may be a bit artificial in the context of this task, the general techniques may be useful elsewhere.
#Pascal
Pascal
program LongestStringChallenge_1(input, output);   var Line: string; Lines: array of string; position, len: integer;   begin if not eoln(input) then begin len := 1; position := 0; readln (line); setlength(lines, len); lines[position] := line; while not eoln(input) do begin readln (line); if length(line) = length(lines[0]) then begin inc(position); inc(len); setlength(lines, len); lines[position] := line; end; if length(line) > length(lines[0]) then begin position := 0; len := 1; setlength(lines, 1); lines[0] := line; end; end; for position := low(lines) to high(lines) do writeln (lines[position]); end; end.
http://rosettacode.org/wiki/Longest_increasing_subsequence
Longest increasing subsequence
Calculate and show here a longest increasing subsequence of the list: { 3 , 2 , 6 , 4 , 5 , 1 } {\displaystyle \{3,2,6,4,5,1\}} And of the list: { 0 , 8 , 4 , 12 , 2 , 10 , 6 , 14 , 1 , 9 , 5 , 13 , 3 , 11 , 7 , 15 } {\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}} Note that a list may have more than one subsequence that is of the maximum length. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet Ref Dynamic Programming #1: Longest Increasing Subsequence on YouTube An efficient solution can be based on Patience sorting.
#Kotlin
Kotlin
// version 1.1.0   fun longestIncreasingSubsequence(x: IntArray): IntArray = when (x.size) { 0 -> IntArray(0) 1 -> x else -> { val n = x.size val p = IntArray(n) val m = IntArray(n + 1) var len = 0 for (i in 0 until n) { var lo = 1 var hi = len while (lo <= hi) { val mid = Math.ceil((lo + hi) / 2.0).toInt() if (x[m[mid]] < x[i]) lo = mid + 1 else hi = mid - 1 } val newLen = lo p[i] = m[newLen - 1] m[newLen] = i if (newLen > len) len = newLen } val s = IntArray(len) var k = m[len] for (i in len - 1 downTo 0) { s[i] = x[k] k = p[k] } s } }   fun main(args: Array<String>) { val lists = listOf( intArrayOf(3, 2, 6, 4, 5, 1), intArrayOf(0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15) ) lists.forEach { println(longestIncreasingSubsequence(it).asList()) } }
http://rosettacode.org/wiki/Loops/Continue
Loops/Continue
Task Show the following output using one loop. 1, 2, 3, 4, 5 6, 7, 8, 9, 10 Try to achieve the result by forcing the next iteration within the loop upon a specific condition, if your language allows it. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Dyalect
Dyalect
for i in 1..10 { print(i, terminator: "") if i % 5 == 0 { print() continue } print(", ", terminator: "") }
http://rosettacode.org/wiki/Loops/Continue
Loops/Continue
Task Show the following output using one loop. 1, 2, 3, 4, 5 6, 7, 8, 9, 10 Try to achieve the result by forcing the next iteration within the loop upon a specific condition, if your language allows it. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Ela
Ela
open monad io   loop n = if n > 10 then do return () else do putStr (show n) putStr f loop (n + 1) where f | n % 5 == 0 = "\r\n" | else = ", "   _ = loop 1 ::: IO
http://rosettacode.org/wiki/Longest_common_substring
Longest common substring
Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are consecutive characters within a string.   This distinguishes them from subsequences, which is any sequence of characters within a string, even if there are extraneous characters in between them. Hence, the longest common subsequence between "thisisatest" and "testing123testing" is "tsitest", whereas the longest common substring is just "test". Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet References Generalize Suffix Tree Ukkonen’s Suffix Tree Construction
#J
J
lcstr=:4 :0 C=. ({.~ 1+$) x=/y M=. >./ (* * * >. * + (_1&|.)@:|:^:2)^:_ C N=. >./ M y {~ (M i. N)-i.-N )
http://rosettacode.org/wiki/Longest_common_substring
Longest common substring
Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are consecutive characters within a string.   This distinguishes them from subsequences, which is any sequence of characters within a string, even if there are extraneous characters in between them. Hence, the longest common subsequence between "thisisatest" and "testing123testing" is "tsitest", whereas the longest common substring is just "test". Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet References Generalize Suffix Tree Ukkonen’s Suffix Tree Construction
#Java
Java
public class LongestCommonSubstring {   public static void main(String[] args) { System.out.println(lcs("testing123testing", "thisisatest")); System.out.println(lcs("test", "thisisatest")); System.out.println(lcs("testing", "sting")); System.out.println(lcs("testing", "thisisasting")); }   static String lcs(String a, String b) { if (a.length() > b.length()) return lcs(b, a);   String res = ""; for (int ai = 0; ai < a.length(); ai++) { for (int len = a.length() - ai; len > 0; len--) {   for (int bi = 0; bi <= b.length() - len; bi++) {   if (a.regionMatches(ai, b, bi, len) && len > res.length()) { res = a.substring(ai, ai + len); } } } } return res; } }
http://rosettacode.org/wiki/Loops/Nested
Loops/Nested
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over [ 1 , … , 20 ] {\displaystyle [1,\ldots ,20]} . The loops iterate rows and columns of the array printing the elements until the value 20 {\displaystyle 20} is met. Specifically, this task also shows how to break out of nested loops. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Smalltalk
Smalltalk
|i|   i := 1. [:exit | Transcript showCR:i. i == 5 ifTrue:[ exit value:'stopped' ]. i := i + 1. ] loopWithExit
http://rosettacode.org/wiki/Loops/Nested
Loops/Nested
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over [ 1 , … , 20 ] {\displaystyle [1,\ldots ,20]} . The loops iterate rows and columns of the array printing the elements until the value 20 {\displaystyle 20} is met. Specifically, this task also shows how to break out of nested loops. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#SPL
SPL
'fill array mx,my = 30 > y, 1..my > x, 1..mx a[x,y] = #.rnd(20)+1 < < 'scan array > y, 1..my > x, 1..mx #.output("x=",x,", y=",y, ", a=",a[x,y]) << a[x,y] = 20 < << x!>mx <
http://rosettacode.org/wiki/Loops/Foreach
Loops/Foreach
Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#XPL0
XPL0
include c:\cxpl\codes; int List, I; [List:= ["Red", "Green", "Blue", "Black", "White"]; for I:= 0, 5-1 do [Text(0, List(I)); CrLf(0)]; ]
http://rosettacode.org/wiki/Loops/Foreach
Loops/Foreach
Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#XSLT
XSLT
<fo:block font-weight="bold">Adults:</fo:block> <xsl:for-each select="person[@age &gt;= 21]"> <fo:block><xsl:value-of select="position()"/>. <xsl:value-of select="@name"/></fo:block> </xsl:for-each>
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers
Luhn test of credit card numbers
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of the digits in the number. Take the first, third, ... and every other odd digit in the reversed digits and sum them to form the partial sum s1 Taking the second, fourth ... and every other even digit in the reversed digits: Multiply each digit by two and sum the digits if the answer is greater than nine to form partial sums for the even digits Sum the partial sums of the even digits to form s2 If s1 + s2 ends in zero then the original number is in the form of a valid credit card number as verified by the Luhn test. For example, if the trial number is 49927398716: Reverse the digits: 61789372994 Sum the odd digits: 6 + 7 + 9 + 7 + 9 + 4 = 42 = s1 The even digits: 1, 8, 3, 2, 9 Two times each even digit: 2, 16, 6, 4, 18 Sum the digits of each multiplication: 2, 7, 6, 4, 9 Sum the last: 2 + 7 + 6 + 4 + 9 = 28 = s2 s1 + s2 = 70 which ends in zero which means that 49927398716 passes the Luhn test Task Write a function/method/procedure/subroutine that will validate a number with the Luhn test, and use it to validate the following numbers: 49927398716 49927398717 1234567812345678 1234567812345670 Related tasks   SEDOL   ISIN
#Perl
Perl
sub luhn_test { my @rev = reverse split //,$_[0]; my ($sum1,$sum2,$i) = (0,0,0);   for(my $i=0;$i<@rev;$i+=2) { $sum1 += $rev[$i]; last if $i == $#rev; $sum2 += 2*$rev[$i+1]%10 + int(2*$rev[$i+1]/10); } return ($sum1+$sum2) % 10 == 0; } print luhn_test('49927398716'); print luhn_test('49927398717'); print luhn_test('1234567812345678'); print luhn_test('1234567812345670');
http://rosettacode.org/wiki/Loops/Infinite
Loops/Infinite
Task Print out       SPAM       followed by a   newline   in an infinite loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#PureBasic
PureBasic
Repeat PrintN("SPAM") ForEver
http://rosettacode.org/wiki/Loops/Infinite
Loops/Infinite
Task Print out       SPAM       followed by a   newline   in an infinite loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Python
Python
while 1: print "SPAM"
http://rosettacode.org/wiki/Loops/Infinite
Loops/Infinite
Task Print out       SPAM       followed by a   newline   in an infinite loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Quackery
Quackery
[ say "SPAM" cr again ]
http://rosettacode.org/wiki/Loops/While
Loops/While
Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreachbas   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Phix
Phix
integer i = 1024 while i!=0 do ?i i = floor(i/2) -- (see note) end while
http://rosettacode.org/wiki/Loops/While
Loops/While
Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreachbas   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#PHL
PHL
var i = 1024; while (i > 0) { printf("%i\n", i); i = i/2; }
http://rosettacode.org/wiki/Loops/Downward_for
Loops/Downward for
Task Write a   for   loop which writes a countdown from   10   to   0. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#R
R
for(i in 10:0) {print(i)}
http://rosettacode.org/wiki/Loops/Downward_for
Loops/Downward for
Task Write a   for   loop which writes a countdown from   10   to   0. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Racket
Racket
  #lang racket   (for ([i (in-range 10 -1 -1)]) (displayln i))  
http://rosettacode.org/wiki/Loops/Do-while
Loops/Do-while
Start with a value at 0. Loop while value mod 6 is not equal to 0. Each time through the loop, add 1 to the value then print it. The loop must execute at least once. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges Reference Do while loop Wikipedia.
#MIPS_Assembly
MIPS Assembly
  .text main: li $s0, 0 # start at 0. li $s1, 6 loop: addi $s0, $s0, 1 # add 1 to $s0 div $s0, $s1 # divide $s0 by $s1. Result is in the multiplication/division registers mfhi $s3 # copy the remainder from the higher multiplication register to $s3 move $a0, $s0 # variable must be in $a0 to print li $v0, 1 # 1 must be in $v0 to tell the assembler to print an integer syscall # print the integer in $a0 bnez $s3, loop # if $s3 is not 0, jump to loop   li $v0, 10 syscall # syscall to end the program  
http://rosettacode.org/wiki/Loops/For
Loops/For
“For”   loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code. Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers. Task Show how two loops may be nested within each other, with the number of iterations performed by the inner for loop being controlled by the outer for loop. Specifically print out the following pattern by using one for loop nested in another: * ** *** **** ***** Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges Reference For loop Wikipedia.
#Fortran
Fortran
C WARNING: This program is not valid ANSI FORTRAN 77 code. It uses C one nonstandard character on the line labelled 5001. Many F77 C compilers should be okay with it, but it is *not* standard. PROGRAM FORLOOP INTEGER I, J   DO 20 I = 1, 5 DO 10 J = 1, I C Print the asterisk. WRITE (*,5001) '*' 10 CONTINUE C Print a newline. WRITE (*,5000) '' 20 CONTINUE   STOP   5000 FORMAT (A) C Standard FORTRAN 77 is completely incapable of completing a C WRITE statement without printing a newline. If you wanted to C write this program in valid F77, you would have to come up with C a creative way of printing varying numbers of asterisks in a C single write statement. C C The dollar sign at the end of the format is a nonstandard C character. It tells the compiler not to print a newline. If you C are actually using FORTRAN 77, you should figure out what your C particular compiler accepts. If you are actually using Fortran C 90 or later, you should replace this line with the commented C line that follows it. 5001 FORMAT (A, $) C5001 FORMAT (A, ADVANCE='NO') END
http://rosettacode.org/wiki/Loops/For_with_a_specified_step
Loops/For with a specified step
Task Demonstrate a   for-loop   where the step-value is greater than one. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Logo
Logo
for [i 2 8 2] [type :i type "|, |] print [who do we appreciate?]
http://rosettacode.org/wiki/Loops/For_with_a_specified_step
Loops/For with a specified step
Task Demonstrate a   for-loop   where the step-value is greater than one. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Lua
Lua
  for i=2,9,2 do print(i) end  
http://rosettacode.org/wiki/Long_multiplication
Long multiplication
Task Explicitly implement   long multiplication. This is one possible approach to arbitrary-precision integer algebra. For output, display the result of   264 * 264. Optionally, verify your result against builtin arbitrary precision support. The decimal representation of   264   is: 18,446,744,073,709,551,616 The output of   264 * 264   is   2128,   and is: 340,282,366,920,938,463,463,374,607,431,768,211,456
#ALGOL_W
ALGOL W
begin  % long multiplication of large integers  %  % large integers are represented by arrays of integers whose absolute  %  % values are in 0 .. ELEMENT_MAX - 1  %  % negative large integers should have negative values in all non-zero  %  % elements  %  % the least significant digits of the large integer are in element 1  % integer ELEMENT_DIGITS; % number of digits in an element of a large  %  % integer  % integer ELEMENT_MAX;  % max absolute value of an element of a large  %  % integer - must be 10^( ELEMENT_DIGITS + 1 )  % integer ELEMENT_COUNT;  % number of elements in each large integer  %  % implements long multiplication, c is set to a * b  %  % c can be the same array as a or b  %  % n is the number of elements in the large integers a, b and c  % procedure longMultiply( integer array a, b, c ( * )  ; integer value n ) ; begin  % multiplies the large integer in b by the integer a, the result  %  % is added to c, starting from offset  %  % overflow is ignored  % procedure multiplyElement( integer value a  ; integer array b, c ( * )  ; integer value offset, n ) ; begin integer carry, cPos; carry := 0; cPos  := offset; for bPos := 1 until highestNonZeroElementPosition( b, ( n + 1 ) - offset ) do begin integer cElement; cElement := c( cPos ) + ( a * b( bPos ) ) + carry; if abs cElement < ELEMENT_MAX then carry := 0 else begin  % have digits to carry  % carry  := cElement div ELEMENT_MAX; cElement := ( abs cElement ) rem ELEMENT_MAX; if carry < 0 then cElement := - cElement end if_no_carry_ ; c( cPos ) := cElement; cPos := cPos + 1 end for_aPos ; if cPos <= n then c( cPos ) := carry end multiplyElement ; integer array mResult ( 1 :: n );  % the result will be computed in mResult, allowing a or b to be c  % for rPos := 1 until n do mResult( rPos ) := 0;  % multiply and add each element to the result  % for aPos := 1 until highestNonZeroElementPosition( a, n ) do begin if a( aPos ) not = 0 then multiplyElement( a( aPos ), b, mResult, aPos, n ) end for_aPos ;  % return the result in c  % for rPos := 1 until n do c( rPos ) := mResult( rPos ) end longMultiply ;  % writes the decimal value of a large integer a with n elements  % procedure writeonLargeInteger( integer array a ( * )  ; integer value n ) ; begin integer aMax; aMax := highestNonZeroElementPosition( a, n ); if aMax < 1 then writeon( "0" ) else begin  % the large integer is non-zero  % writeon( i_w := 1, s_w := 0, a( aMax ) ); % highest element  %  % handle the remaining elements - show leading zeros  % for aPos := aMax - 1 step -1 until 1 do begin integer v; integer array digits ( 1 :: ELEMENT_DIGITS ); v := abs a( aPos ); for dPos := ELEMENT_DIGITS step -1 until 1 do begin digits( dPos ) := v rem 10; v  := v div 10 end for_dPos; for dPos := 1 until ELEMENT_DIGITS do writeon( i_w := 1, s_w := 0, digits( dPos ) ) end for_aPos end if_aMax_lt_1_ end writeonLargeInteger ;  % returns the position of the highest non-zero element of the large  %  % integer a with n elements  % integer procedure highestNonZeroElementPosition( integer array a ( * )  ; integer value n ) ; begin integer aMax; aMax := n; while aMax > 0 and a( aMax ) = 0 do aMax := aMax - 1; aMax end highestNonZeroElementPosition ;  % allow each element to contain 4 decimal digits, so element by element %  % multiplication won't overflow 32-bits  % ELEMENT_DIGITS := 4; ELEMENT_MAX  := 10000; ELEMENT_COUNT  := 12; % allows up to 48 digits - enough for the task % begin integer array twoTo64, twoTo128 ( 1 :: ELEMENT_COUNT ); integer pwr;  % construct 2^64 in twoTo64  % for tPos := 2 until ELEMENT_COUNT do twoTo64( tPos ) := 0; twoTo64( 1 ) := 2; pwr  := 1; while pwr < 64 do begin longMultiply( twoTo64, twoTo64, twoTo64, ELEMENT_COUNT ); pwr := pwr * 2 end while_pwr_lt_64 ;  % construct 2^128  % longMultiply( twoTo64, twoTo64, twoTo128, ELEMENT_COUNT ); write( "2^128: " ); writeonLargeInteger( twoTo128, ELEMENT_COUNT ) end end.
http://rosettacode.org/wiki/Literals/String
Literals/String
Task Show literal specification of characters and strings. If supported, show how the following work:   verbatim strings   (quotes where escape sequences are quoted literally)   here-strings   Also, discuss which quotes expand variables. Related tasks   Special characters   Here document Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Arturo
Arturo
str: "Hello world"   print [str "->" type str]   fullLineStr: « This is a full-line string   print [fullLineStr "->" type fullLineStr]   multiline: { This is a multi-line string }   print [multiline "->" type multiline]   verbatim: {: This is a verbatim multi-line string :}   print [verbatim "->" type verbatim]
http://rosettacode.org/wiki/Literals/String
Literals/String
Task Show literal specification of characters and strings. If supported, show how the following work:   verbatim strings   (quotes where escape sequences are quoted literally)   here-strings   Also, discuss which quotes expand variables. Related tasks   Special characters   Here document Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#AutoHotkey
AutoHotkey
"c" ; character "text" ; string hereString = ; with interpolation of %variables% ( "<>" the time is %A_Now% \! )   hereString2 = ; with same line comments allowed, without interpolation of variables (Comments % literal %A_Now% ; no interpolation here )
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#J
J
NB. create a multi-line literal elements =: CRLF -.~ noun define hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminum silicon phosphorous sulfur chlorine argon potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon cesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson ) NB. same under words space_separated_elements =: ]&.:;: elements tally=: # ;: elements last_element=: _1 {:: ;: elements revision=: '2020-03-23' 'Last revision: ', revision 'Number of elements: ' , ": tally 'Last element: ', last_element 'first and last 30 characters:' 30 ;&({.&space_separated_elements) _30 Last revision: 2020-03-23 Number of elements: 118 Last element: oganesson first and last 30 characters: ┌──────────────────────────────┬──────────────────────────────┐ │hydrogen helium lithium beryll│vermorium tennessine oganesson│ └──────────────────────────────┴──────────────────────────────┘
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#jq
jq
# FOR FUTURE EDITORS: # To add chemical elements, modify the CHEMICAL_ELEMENTS function, # ensuring that the date is updated properly and that there is at least one # space between the element names after concatenation of the strings. # Do not include any of the "unnamed" chemical element names such as ununennium.   def CHEMICAL_ELEMENTS: {date: "Wed Jun 23 00:00:00 EDT 2021", elements: (   "hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon " + "sodium magnesium aluminum silicon phosphorus sulfur chlorine argon potassium " + "calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper " + "zinc gallium germanium arsenic selenium bromine krypton rubidium strontium " + "yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium " + "silver cadmium indium tin antimony tellurium iodine xenon cesium barium " + "lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium " + "terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum " + "tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth " + "polonium astatine radon francium radium actinium thorium protactinium uranium " + "neptunium plutonium americium curium berkelium californium einsteinium fermium " + "mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium " + "meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium " + "livermorium tennessine oganesson"   ) } ;   def chemical_elements_array: CHEMICAL_ELEMENTS.elements # remove leading and trailing whitespace | sub("^ *";"") | sub(" *$";"") # return a list after splitting using whitespace between words as a separator | [splits("[ \t]+")] ;   def report: chemical_elements_array as $a | "List last revised: \(CHEMICAL_ELEMENTS.date)", "Length of element list: \($a|length)", "Last element in list: \($a[-1])";   report
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Julia
Julia
using Dates   # FOR FUTURE EDITORS: # # Add to this list by adding more lines of text to this listing, placing the # new words of text before the last """ below, with all entries separated by # spaces. # const CHEMICAL_ELEMENTS = """   hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminum silicon phosphorus sulfur chlorine argon potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon cesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson   """ # # END OF ABOVE LISTING--DO NOT ADD ELEMENTS BELOW THIS LINE #   const EXCLUDED = split(strip( "ununennium unquadnilium triunhexium penthextrium penthexpentium " * " septhexunium octenntrium ennennbium"), r"\s+")   function process_chemical_element_list(s = CHEMICAL_ELEMENTS) # remove leading and trailing whitespace s = strip(s) # return a list after splitting using whitespace between words as a separator return [element for element in split(s, r"\s+") if !(element in EXCLUDED)] end   function report() filedate = Dates.unix2datetime(mtime(@__FILE__)) element_list = process_chemical_element_list() element_count = length(element_list) last_element_in_list = element_list[end]   println("File last revised (formatted as dateTtime): ", filedate, " GMT") println("Length of element list: ", element_count) println("last element in list: ", last_element_in_list) end   report()  
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Kotlin
Kotlin
import java.time.Instant   const val elementsChunk = """ hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminum silicon phosphorous sulfur chlorine argon potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon cesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson """   const val unamedElementsChunk = """ ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium """   fun main() { fun String.splitToList() = trim().split("\\s+".toRegex()); val elementsList = elementsChunk.splitToList() .filterNot(unamedElementsChunk.splitToList().toSet()::contains) println("Last revision Date: ${Instant.now()}") println("Number of elements: ${elementsList.size}") println("Last element  : ${elementsList.last()}") println("The elements are  : ${elementsList.joinToString(" ", limit = 5)}") }
http://rosettacode.org/wiki/List_rooted_trees
List rooted trees
You came back from grocery shopping.   After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink.   In doing so, you realize that there are various ways of nesting the bags, with all bags viewed as identical. If we use a matching pair of parentheses to represent a bag, the ways are: For 1 bag, there's one way: () <- a bag for 2 bags, there's one way: (()) <- one bag in another for 3 bags, there are two: ((())) <- 3 bags nested Russian doll style (()()) <- 2 bags side by side, inside the third for 4 bags, four: (()()()) ((())()) ((()())) (((()))) Note that because all bags are identical, the two 4-bag strings ((())()) and (()(())) represent the same configuration. It's easy to see that each configuration for n bags represents a n-node rooted tree, where a bag is a tree node, and a bag with its content forms a subtree. The outermost bag is the tree root. Number of configurations for given n is given by OEIS A81. Task Write a program that, when given n, enumerates all ways of nesting n bags.   You can use the parentheses notation above, or any tree representation that's unambiguous and preferably intuitive. This task asks for enumeration of trees only; for counting solutions without enumeration, that OEIS page lists various formulas, but that's not encouraged by this task, especially if implementing it would significantly increase code size. As an example output, run 5 bags.   There should be 9 ways.
#Haskell
Haskell
-- break n down into sum of smaller integers parts :: Int -> [[(Int, Int)]] parts n = f n 1 where f n x | n == 0 = [[]] | x > n = [] | otherwise = f n (x + 1) ++ concatMap (\c -> map ((c, x) :) (f (n - c * x) (x + 1))) [1 .. n `div` x]   -- choose n strings out of a list and join them pick :: Int -> [String] -> [String] pick _ [] = [] pick 0 _ = [""] pick n aa@(a:as) = map (a ++) (pick (n - 1) aa) ++ pick n as   -- pick parts to build a series of subtrees that add up to n-1, -- then wrap them up trees :: Int -> [String] trees n = map (\x -> "(" ++ x ++ ")") $ concatMap (foldr (prod . build) [""]) (parts (n - 1)) where build (c, x) = pick c $ trees x prod aa bb = [ a ++ b | a <- aa , b <- bb ]   main :: IO () main = mapM_ putStrLn $ trees 5
http://rosettacode.org/wiki/Literals/Integer
Literals/Integer
Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be interpreted by the compiler or interpreter as an integer written to a given base. Also show any other ways of expressing literals, e.g. for different types of integers. Related task   Literals/Floating point
#Arturo
Arturo
num: 18966   print [num "->" type num]
http://rosettacode.org/wiki/Literals/Integer
Literals/Integer
Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be interpreted by the compiler or interpreter as an integer written to a given base. Also show any other ways of expressing literals, e.g. for different types of integers. Related task   Literals/Floating point
#AutoHotkey
AutoHotkey
If (727 == 0x2d7) MsgBox true
http://rosettacode.org/wiki/Logical_operations
Logical operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a function that takes two logical (boolean) values, and outputs the result of "and" and "or" on both arguments as well as "not" on the first arguments. If the programming language doesn't provide a separate type for logical values, use the type most commonly used for that purpose. If the language supports additional logical operations on booleans such as XOR, list them as well.
#Aikido
Aikido
  function logic(a,b) { println("a AND b: " + (a && b)) println("a OR b: " + (a || b)) println("NOT a: " + (!a)) }  
http://rosettacode.org/wiki/Logical_operations
Logical operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a function that takes two logical (boolean) values, and outputs the result of "and" and "or" on both arguments as well as "not" on the first arguments. If the programming language doesn't provide a separate type for logical values, use the type most commonly used for that purpose. If the language supports additional logical operations on booleans such as XOR, list them as well.
#Aime
Aime
void out(integer a, integer b) { o_integer(a && b); o_byte('\n'); o_integer(a || b); o_byte('\n'); o_integer(!a); o_byte('\n'); }
http://rosettacode.org/wiki/Loops/N_plus_one_half
Loops/N plus one half
Quite often one needs loops which, in the last iteration, execute only part of the loop body. Goal Demonstrate the best way to do this. Task Write a loop which writes the comma-separated list 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 using separate output statements for the number and the comma from within the body of the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#UNIX_Shell
UNIX Shell
for(( Z=1; Z<=10; Z++ )); do echo -e "$Z\c" if (( Z != 10 )); then echo -e ", \c" fi done
http://rosettacode.org/wiki/Loops/N_plus_one_half
Loops/N plus one half
Quite often one needs loops which, in the last iteration, execute only part of the loop body. Goal Demonstrate the best way to do this. Task Write a loop which writes the comma-separated list 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 using separate output statements for the number and the comma from within the body of the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#UnixPipes
UnixPipes
yes \ | cat -n | head -n 10 | paste -d\ - <(yes , | head -n 9) | xargs echo
http://rosettacode.org/wiki/Literals/Floating_point
Literals/Floating point
Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF/ABNF/EBNF defining allowable formats for your language. Related tasks   Literals/Integer   Extreme floating point values
#Eiffel
Eiffel
  1. 1.23 1e-5 .5 1.23E4  
http://rosettacode.org/wiki/Literals/Floating_point
Literals/Floating point
Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF/ABNF/EBNF defining allowable formats for your language. Related tasks   Literals/Integer   Extreme floating point values
#Elena
Elena
real r := 1; r := 23.2r; r := 1.2e+11r;
http://rosettacode.org/wiki/Literals/Floating_point
Literals/Floating point
Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF/ABNF/EBNF defining allowable formats for your language. Related tasks   Literals/Integer   Extreme floating point values
#Elixir
Elixir
iex(180)> 0.123 0.123 iex(181)> -123.4 -123.4 iex(182)> 1.23e4 1.23e4 iex(183)> 1.2e-3 0.0012 iex(184)> 1.23E4 1.23e4 iex(185)> 10_000.0 1.0e4 iex(186)> .5 ** (SyntaxError) iex:186: syntax error before: '.'   iex(186)> 2. + 3 ** (CompileError) iex:186: invalid call 2.+(3)   iex(187)> 1e4 ** (SyntaxError) iex:187: syntax error before: e4
http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#Fortran
Fortran
  program longyear use iso_fortran_env, only: output_unit, input_unit implicit none   integer :: start, ende, i, counter integer, parameter :: line_break=10   write(output_unit,*) "Enter beginning of interval" read(input_unit,*) start write(output_unit,*) "Enter end of interval" read(input_unit,*) ende   if (start>=ende) error stop "Last year must be after first year!"   counter = 0 do i = start, ende if (is_long_year(i)) then write(output_unit,'(I0,x)', advance="no") i counter = counter + 1 if (modulo(counter,line_break) == 0) write(output_unit,*) end if end do contains pure function p(year) integer, intent(in) :: year integer :: p   p = modulo(year + year/4 - year/100 + year/400, 7) end function p   pure function is_long_year(year) integer, intent(in) :: year logical :: is_long_year   is_long_year = p(year) == 4 .or. p(year-1) == 3 end function is_long_year end program longyear  
http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#Go
Go
package main   import ( "fmt" "time" )   func main() { centuries := []string{"20th", "21st", "22nd"} starts := []int{1900, 2000, 2100} for i := 0; i < len(centuries); i++ { var longYears []int fmt.Printf("\nLong years in the %s century:\n", centuries[i]) for j := starts[i]; j < starts[i] + 100; j++ { t := time.Date(j, time.December, 28, 0, 0, 0, 0, time.UTC) if _, week := t.ISOWeek(); week == 53 { longYears = append(longYears, j) } } fmt.Println(longYears) } }
http://rosettacode.org/wiki/Long_primes
Long primes
A   long prime   (as defined here)   is a prime number whose reciprocal   (in decimal)   has a   period length   of one less than the prime number. Long primes   are also known as:   base ten cyclic numbers   full reptend primes   golden primes   long period primes   maximal period primes   proper primes Another definition:   primes   p   such that the decimal expansion of   1/p   has period   p-1,   which is the greatest period possible for any integer. Example 7   is the first long prime,   the reciprocal of seven is   1/7,   which is equal to the repeating decimal fraction   0.142857142857··· The length of the   repeating   part of the decimal fraction is six,   (the underlined part)   which is one less than the (decimal) prime number   7. Thus   7   is a long prime. There are other (more) general definitions of a   long prime   which include wording/verbiage for bases other than ten. Task   Show all long primes up to   500   (preferably on one line).   Show the   number   of long primes up to        500   Show the   number   of long primes up to     1,000   Show the   number   of long primes up to     2,000   Show the   number   of long primes up to     4,000   Show the   number   of long primes up to     8,000   Show the   number   of long primes up to   16,000   Show the   number   of long primes up to   32,000   Show the   number   of long primes up to   64,000   (optional)   Show all output here. Also see   Wikipedia: full reptend prime   MathWorld: full reptend prime   OEIS: A001913
#FreeBASIC
FreeBASIC
' version 01-02-2019 ' compile with: fbc -s console   Dim Shared As UByte prime()   Sub find_primes(n As UInteger)   ReDim prime(n) Dim As UInteger i, k   ' need only to consider odd primes, 2 has no repetion For i = 3 To n Step 2 If prime(i) = 0 Then For k = i * i To n Step i + i prime(k) = 1 Next End If Next   End Sub   Function find_period(p As UInteger) As UInteger ' finds period for every positive number Dim As UInteger period, r = 1   Do r = (r * 10) Mod p period += 1 If r <= 1 Then Return period Loop   End Function   ' ------=< MAIN >=------   #Define max 64000 Dim As UInteger p = 3, n1 = 3, n2 = 500, i, n50, count   find_primes(max) Print "Long primes upto 500 are ";   For i = n1 To n2 Step 2 If prime(i) = 0 Then If i -1 = find_period(i) Then If n50 <= 50 Then Print Str(i); " "; End If count += 1 End If End If Next   Print : Print   Do Print "There are "; Str(count); " long primes upto "; Str(n2)   n1 = n2 +1 n2 += n2 If n1 > max Then Exit Do   For i = n1 To n2 Step 2 If prime(i) = 0 Then If i -1 = find_period(i) Then count += 1 End If End If Next Loop   ' empty keyboard buffer While Inkey <> "" : Wend Print : Print "hit any key to end program" Sleep End
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously
Loop over multiple arrays simultaneously
Task Loop over multiple arrays   (or lists or tuples or whatever they're called in your language)   and display the   i th   element of each. Use your language's   "for each"   loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: (a,b,c) (A,B,C) (1,2,3) to produce the output: aA1 bB2 cC3 If possible, also describe what happens when the arrays are of different lengths. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#BASIC256
BASIC256
dim arr1$(3) : arr1$ = {"a", "b", "c"} dim arr2$(3) : arr2$ = {"A", "B", "C"} dim arr3(3)  : arr3 = {1, 2, 3}   for i = 0 to 2 print arr1$[i]; arr2$[i]; arr3[i] next i end
http://rosettacode.org/wiki/Loops/Break
Loops/Break
Task Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive). If a number is 10, stop the loop after printing it, and do not generate any further numbers. Otherwise, generate and print a second random number before restarting the loop. If the number 10 is never generated as the first number in a loop, loop forever. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges
#Chapel
Chapel
use Random;   var r = new RandomStream(); while true { var a = floor(r.getNext() * 20):int; writeln(a); if a == 10 then break; var b = floor(r.getNext() * 20):int; writeln(b); } delete r;
http://rosettacode.org/wiki/Loops/Break
Loops/Break
Task Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive). If a number is 10, stop the loop after printing it, and do not generate any further numbers. Otherwise, generate and print a second random number before restarting the loop. If the number 10 is never generated as the first number in a loop, loop forever. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges
#Chef
Chef
(loop [[a b & more] (repeatedly #(rand-int 20))] (println a) (when-not (= 10 a) (println b) (recur more)))
http://rosettacode.org/wiki/Longest_common_subsequence
Longest common subsequence
Introduction Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string. The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings. Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be strings drawn from an alphabet Σ of size s, containing every distinct symbol in A + B. An ordered pair (i, j) will be referred to as a match if A[i] = B[j], where 0 < i ≤ m and 0 < j ≤ n. Define a non-strict product-order (≤) over ordered pairs, such that (i1, j1) ≤ (i2, j2) ⇔ i1 ≤ i2 and j1 ≤ j2. We define (≥) similarly. We say m1, m2 are comparable if either m1 ≤ m2 or m1 ≥ m2 holds. If i1 < i2 and j2 < j1 (or i2 < i1 and j1 < j2) then neither m1 ≤ m2 nor m1 ≥ m2 are possible; and we say m1, m2 are incomparable. We also define the strict product-order (<) over ordered pairs, such that (i1, j1) < (i2, j2) ⇔ i1 < i2 and j1 < j2. We define (>) similarly. Given a set of matches M, a chain C is a subset of M consisting of at least one element m; and where either m1 < m2 or m1 > m2 for every pair of distinct elements m1 and m2. An antichain D is any subset of M in which every pair of distinct elements m1 and m2 are incomparable. The set M represents a relation over match pairs: M[i, j] ⇔ (i, j) ∈ M. A chain C can be visualized as a curve which strictly increases as it passes through each match pair in the m*n coordinate space. Finding an LCS can be restated as the problem of finding a chain of maximum cardinality p over the set of matches M. According to [Dilworth 1950], this cardinality p equals the minimum number of disjoint antichains into which M can be decomposed. Note that such a decomposition into the minimal number p of disjoint antichains may not be unique. Contours Forward Contours FC[k] of class k are defined inductively, as follows: FC[0] consists of those elements m1 for which there exists no element m2 such that m2 < m1. FC[k] consists of those elements m1 for which there exists no element m2 such that m2 < m1; and where neither m1 nor m2 are contained in FC[l] for any class l < k. Reverse Contours RC[k] of class k are defined similarly. Members of the Meet (∧), or Infimum of a Forward Contour are referred to as its Dominant Matches: those m1 for which there exists no m2 such that m2 < m1. Members of the Join (∨), or Supremum of a Reverse Contour are referred to as its Dominant Matches: those m1 for which there exists no m2 such that m2 > m1. Where multiple Dominant Matches exist within a Meet (or within a Join, respectively) the Dominant Matches will be incomparable to each other. Background Where the number of symbols appearing in matches is small relative to the length of the input strings, reuse of the symbols increases; and the number of matches will tend towards quadratic, O(m*n) growth. This occurs, for example, in the Bioinformatics application of nucleotide and protein sequencing. The divide-and-conquer approach of [Hirschberg 1975] limits the space required to O(n). However, this approach requires O(m*n) time even in the best case. This quadratic time dependency may become prohibitive, given very long input strings. Thus, heuristics are often favored over optimal Dynamic Programming solutions. In the application of comparing file revisions, records from the input files form a large symbol space; and the number of symbols approaches the length of the LCS. In this case the number of matches reduces to linear, O(n) growth. A binary search optimization due to [Hunt and Szymanski 1977] can be applied to the basic Dynamic Programming approach, resulting in an expected performance of O(n log m). Performance can degrade to O(m*n log m) time in the worst case, as the number of matches grows to O(m*n). Note [Rick 2000] describes a linear-space algorithm with a time bound of O(n*s + p*min(m, n - p)). Legend A, B are input strings of lengths m, n respectively p is the length of the LCS M is the set of match pairs (i, j) such that A[i] = B[j] r is the magnitude of M s is the magnitude of the alphabet Σ of distinct symbols in A + B References [Dilworth 1950] "A decomposition theorem for partially ordered sets" by Robert P. Dilworth, published January 1950, Annals of Mathematics [Volume 51, Number 1, pp. 161-166] [Goeman and Clausen 2002] "A New Practical Linear Space Algorithm for the Longest Common Subsequence Problem" by Heiko Goeman and Michael Clausen, published 2002, Kybernetika [Volume 38, Issue 1, pp. 45-66] [Hirschberg 1975] "A linear space algorithm for computing maximal common subsequences" by Daniel S. Hirschberg, published June 1975 Communications of the ACM [Volume 18, Number 6, pp. 341-343] [Hunt and McIlroy 1976] "An Algorithm for Differential File Comparison" by James W. Hunt and M. Douglas McIlroy, June 1976 Computing Science Technical Report, Bell Laboratories 41 [Hunt and Szymanski 1977] "A Fast Algorithm for Computing Longest Common Subsequences" by James W. Hunt and Thomas G. Szymanski, published May 1977 Communications of the ACM [Volume 20, Number 5, pp. 350-353] [Rick 2000] "Simple and fast linear space computation of longest common subsequences" by Claus Rick, received 17 March 2000, Information Processing Letters, Elsevier Science [Volume 75, pp. 275–281] Examples The sequences "1234" and "1224533324" have an LCS of "1234": 1234 1224533324 For a string example, consider the sequences "thisisatest" and "testing123testing". An LCS would be "tsitest": thisisatest testing123testing In this puzzle, your code only needs to deal with strings. Write a function which returns an LCS of two strings (case-sensitive). You don't need to show multiple LCS's. For more information on this problem please see Wikipedia. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Common_Lisp
Common Lisp
(defun longest-common-subsequence (array1 array2) (let* ((l1 (length array1)) (l2 (length array2)) (results (make-array (list l1 l2) :initial-element nil))) (declare (dynamic-extent results)) (labels ((lcs (start1 start2) ;; if either sequence is empty, return (() 0) (if (or (eql start1 l1) (eql start2 l2)) (list '() 0) ;; otherwise, return any memoized value (let ((result (aref results start1 start2))) (if (not (null result)) result ;; otherwise, compute and store a value (setf (aref results start1 start2) (if (eql (aref array1 start1) (aref array2 start2)) ;; if they start with the same element, ;; move forward in both sequences (destructuring-bind (seq len) (lcs (1+ start1) (1+ start2)) (list (cons (aref array1 start1) seq) (1+ len))) ;; otherwise, move ahead in each separately, ;; and return the better result. (let ((a (lcs (1+ start1) start2)) (b (lcs start1 (1+ start2)))) (if (> (second a) (second b)) a b))))))))) (destructuring-bind (seq len) (lcs 0 0) (values (coerce seq (type-of array1)) len)))))
http://rosettacode.org/wiki/Look-and-say_sequence
Look-and-say sequence
The   Look and say sequence   is a recursively defined sequence of numbers studied most notably by   John Conway. The   look-and-say sequence   is also known as the   Morris Number Sequence,   after cryptographer Robert Morris,   and the puzzle   What is the next number in the sequence 1,   11,   21,   1211,   111221?   is sometimes referred to as the Cuckoo's Egg,   from a description of Morris in Clifford Stoll's book   The Cuckoo's Egg. Sequence Definition Take a decimal number Look at the number, visually grouping consecutive runs of the same digit. Say the number, from left to right, group by group; as how many of that digit there are - followed by the digit grouped. This becomes the next number of the sequence. An example: Starting with the number 1,   you have one 1 which produces 11 Starting with 11,   you have two 1's.   I.E.:   21 Starting with 21,   you have one 2, then one 1.   I.E.:   (12)(11) which becomes 1211 Starting with 1211,   you have one 1, one 2, then two 1's.   I.E.:   (11)(12)(21) which becomes 111221 Task Write a program to generate successive members of the look-and-say sequence. Related tasks   Fours is the number of letters in the ...   Number names   Self-describing numbers   Self-referential sequence   Spelling of ordinal numbers See also   Look-and-Say Numbers (feat John Conway), A Numberphile Video.   This task is related to, and an application of, the Run-length encoding task.   Sequence A005150 on The On-Line Encyclopedia of Integer Sequences.
#BQN
BQN
LookSay ← ∾´((⊑∾˜ ≠+'0'˙)¨1↓((+`»≠⊢)⊸⊔))   >((⌈´≠¨)↑¨⊢) LookSay⍟(↕15)"1"
http://rosettacode.org/wiki/Longest_string_challenge
Longest string challenge
Background This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the challenge and fun part came through the introduction of restrictions. Experience has shown that the original restrictions required some adjustment to bring out the intent of the challenge and make it suitable for Rosetta Code. Basic problem statement Write a program that reads lines from standard input and, upon end of file, writes the longest line to standard output. If there are ties for the longest line, the program writes out all the lines that tie. If there is no input, the program should produce no output. Task Implement a solution to the basic problem that adheres to the spirit of the restrictions (see below). Describe how you circumvented or got around these 'restrictions' and met the 'spirit' of the challenge. Your supporting description may need to describe any challenges to interpreting the restrictions and how you made this interpretation. You should state any assumptions, warnings, or other relevant points. The central idea here is to make the task a bit more interesting by thinking outside of the box and perhaps by showing off the capabilities of your language in a creative way. Because there is potential for considerable variation between solutions, the description is key to helping others see what you've done. This task is likely to encourage a variety of different types of solutions. They should be substantially different approaches. Given the input: a bb ccc ddd ee f ggg the output should be (possibly rearranged): ccc ddd ggg Original list of restrictions No comparison operators may be used. No arithmetic operations, such as addition and subtraction, may be used. The only datatypes you may use are integer and string. In particular, you may not use lists. Do not re-read the input file. Avoid using files as a replacement for lists (this restriction became apparent in the discussion). Intent of restrictions Because of the variety of languages on Rosetta Code and the wide variety of concepts used in them, there needs to be a bit of clarification and guidance here to get to the spirit of the challenge and the intent of the restrictions. The basic problem can be solved very conventionally, but that's boring and pedestrian. The original intent here wasn't to unduly frustrate people with interpreting the restrictions, it was to get people to think outside of their particular box and have a bit of fun doing it. The guiding principle here should be to be creative in demonstrating some of the capabilities of the programming language being used. If you need to bend the restrictions a bit, explain why and try to follow the intent. If you think you've implemented a 'cheat', call out the fragment yourself and ask readers if they can spot why. If you absolutely can't get around one of the restrictions, explain why in your description. Now having said that, the restrictions require some elaboration. In general, the restrictions are meant to avoid the explicit use of these features. "No comparison operators may be used" - At some level there must be some test that allows the solution to get at the length and determine if one string is longer. Comparison operators, in particular any less/greater comparison should be avoided. Representing the length of any string as a number should also be avoided. Various approaches allow for detecting the end of a string. Some of these involve implicitly using equal/not-equal; however, explicitly using equal/not-equal should be acceptable. "No arithmetic operations" - Again, at some level something may have to advance through the string. Often there are ways a language can do this implicitly advance a cursor or pointer without explicitly using a +, - , ++, --, add, subtract, etc. The datatype restrictions are amongst the most difficult to reinterpret. In the language of the original challenge strings are atomic datatypes and structured datatypes like lists are quite distinct and have many different operations that apply to them. This becomes a bit fuzzier with languages with a different programming paradigm. The intent would be to avoid using an easy structure to accumulate the longest strings and spit them out. There will be some natural reinterpretation here. To make this a bit more concrete, here are a couple of specific examples: In C, a string is an array of chars, so using a couple of arrays as strings is in the spirit while using a second array in a non-string like fashion would violate the intent. In APL or J, arrays are the core of the language so ruling them out is unfair. Meeting the spirit will come down to how they are used. Please keep in mind these are just examples and you may hit new territory finding a solution. There will be other cases like these. Explain your reasoning. You may want to open a discussion on the talk page as well. The added "No rereading" restriction is for practical reasons, re-reading stdin should be broken. I haven't outright banned the use of other files but I've discouraged them as it is basically another form of a list. Somewhere there may be a language that just sings when doing file manipulation and where that makes sense; however, for most there should be a way to accomplish without resorting to an externality. At the end of the day for the implementer this should be a bit of fun. As an implementer you represent the expertise in your language, the reader may have no knowledge of your language. For the reader it should give them insight into how people think outside the box in other languages. Comments, especially for non-obvious (to the reader) bits will be extremely helpful. While the implementations may be a bit artificial in the context of this task, the general techniques may be useful elsewhere.
#Perl
Perl
#!/usr/bin/perl -n END{ print $all }   substr($_, length($l)) and $all = $l = $_ or substr($l, length) or $all .= $_;
http://rosettacode.org/wiki/Longest_string_challenge
Longest string challenge
Background This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the challenge and fun part came through the introduction of restrictions. Experience has shown that the original restrictions required some adjustment to bring out the intent of the challenge and make it suitable for Rosetta Code. Basic problem statement Write a program that reads lines from standard input and, upon end of file, writes the longest line to standard output. If there are ties for the longest line, the program writes out all the lines that tie. If there is no input, the program should produce no output. Task Implement a solution to the basic problem that adheres to the spirit of the restrictions (see below). Describe how you circumvented or got around these 'restrictions' and met the 'spirit' of the challenge. Your supporting description may need to describe any challenges to interpreting the restrictions and how you made this interpretation. You should state any assumptions, warnings, or other relevant points. The central idea here is to make the task a bit more interesting by thinking outside of the box and perhaps by showing off the capabilities of your language in a creative way. Because there is potential for considerable variation between solutions, the description is key to helping others see what you've done. This task is likely to encourage a variety of different types of solutions. They should be substantially different approaches. Given the input: a bb ccc ddd ee f ggg the output should be (possibly rearranged): ccc ddd ggg Original list of restrictions No comparison operators may be used. No arithmetic operations, such as addition and subtraction, may be used. The only datatypes you may use are integer and string. In particular, you may not use lists. Do not re-read the input file. Avoid using files as a replacement for lists (this restriction became apparent in the discussion). Intent of restrictions Because of the variety of languages on Rosetta Code and the wide variety of concepts used in them, there needs to be a bit of clarification and guidance here to get to the spirit of the challenge and the intent of the restrictions. The basic problem can be solved very conventionally, but that's boring and pedestrian. The original intent here wasn't to unduly frustrate people with interpreting the restrictions, it was to get people to think outside of their particular box and have a bit of fun doing it. The guiding principle here should be to be creative in demonstrating some of the capabilities of the programming language being used. If you need to bend the restrictions a bit, explain why and try to follow the intent. If you think you've implemented a 'cheat', call out the fragment yourself and ask readers if they can spot why. If you absolutely can't get around one of the restrictions, explain why in your description. Now having said that, the restrictions require some elaboration. In general, the restrictions are meant to avoid the explicit use of these features. "No comparison operators may be used" - At some level there must be some test that allows the solution to get at the length and determine if one string is longer. Comparison operators, in particular any less/greater comparison should be avoided. Representing the length of any string as a number should also be avoided. Various approaches allow for detecting the end of a string. Some of these involve implicitly using equal/not-equal; however, explicitly using equal/not-equal should be acceptable. "No arithmetic operations" - Again, at some level something may have to advance through the string. Often there are ways a language can do this implicitly advance a cursor or pointer without explicitly using a +, - , ++, --, add, subtract, etc. The datatype restrictions are amongst the most difficult to reinterpret. In the language of the original challenge strings are atomic datatypes and structured datatypes like lists are quite distinct and have many different operations that apply to them. This becomes a bit fuzzier with languages with a different programming paradigm. The intent would be to avoid using an easy structure to accumulate the longest strings and spit them out. There will be some natural reinterpretation here. To make this a bit more concrete, here are a couple of specific examples: In C, a string is an array of chars, so using a couple of arrays as strings is in the spirit while using a second array in a non-string like fashion would violate the intent. In APL or J, arrays are the core of the language so ruling them out is unfair. Meeting the spirit will come down to how they are used. Please keep in mind these are just examples and you may hit new territory finding a solution. There will be other cases like these. Explain your reasoning. You may want to open a discussion on the talk page as well. The added "No rereading" restriction is for practical reasons, re-reading stdin should be broken. I haven't outright banned the use of other files but I've discouraged them as it is basically another form of a list. Somewhere there may be a language that just sings when doing file manipulation and where that makes sense; however, for most there should be a way to accomplish without resorting to an externality. At the end of the day for the implementer this should be a bit of fun. As an implementer you represent the expertise in your language, the reader may have no knowledge of your language. For the reader it should give them insight into how people think outside the box in other languages. Comments, especially for non-obvious (to the reader) bits will be extremely helpful. While the implementations may be a bit artificial in the context of this task, the general techniques may be useful elsewhere.
#Phix
Phix
with javascript_semantics --integer fn = open(command_line()[2],"r") -- (reading the source file) sequence fn = unix_dict()[1..40]&-1 function allx(string line) line[1..-1] = 'x' return line end function function longest(string mask) -- object line = gets(fn) object line = fn[1]; fn = fn[2..$]; if atom(line) then return mask end if string newmask = allx(line) if not match(mask,newmask) then return longest(mask) end if mask = longest(newmask) if match(mask,newmask) then -- puts(1,line) printf(1,"%s\n",line) end if return mask end function {} = longest("x") --close(fn)
http://rosettacode.org/wiki/Longest_increasing_subsequence
Longest increasing subsequence
Calculate and show here a longest increasing subsequence of the list: { 3 , 2 , 6 , 4 , 5 , 1 } {\displaystyle \{3,2,6,4,5,1\}} And of the list: { 0 , 8 , 4 , 12 , 2 , 10 , 6 , 14 , 1 , 9 , 5 , 13 , 3 , 11 , 7 , 15 } {\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}} Note that a list may have more than one subsequence that is of the maximum length. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet Ref Dynamic Programming #1: Longest Increasing Subsequence on YouTube An efficient solution can be based on Patience sorting.
#Lua
Lua
function buildLIS(seq) local piles = { { {table.remove(seq, 1), nil} } } while #seq>0 do local x=table.remove(seq, 1) for j=1,#piles do if piles[j][#piles[j]][1]>x then table.insert(piles[j], {x, (piles[j-1] and #piles[j-1])}) break elseif j==#piles then table.insert(piles, {{x, #piles[j]}}) end end end local t={} table.insert(t, piles[#piles][1][1]) local p=piles[#piles][1][2] for i=#piles-1,1,-1 do table.insert(t, piles[i][p][1]) p=piles[i][p][2] end table.sort(t) print(unpack(t)) end   buildLIS({3,2,6,4,5,1}) buildLIS({0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15})  
http://rosettacode.org/wiki/Loops/Continue
Loops/Continue
Task Show the following output using one loop. 1, 2, 3, 4, 5 6, 7, 8, 9, 10 Try to achieve the result by forcing the next iteration within the loop upon a specific condition, if your language allows it. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Elixir
Elixir
defmodule Loops do def continue do Enum.each(1..10, fn i -> IO.write i IO.write if rem(i,5)==0, do: "\n", else: ", " end) end end   Loops.continue
http://rosettacode.org/wiki/Loops/Continue
Loops/Continue
Task Show the following output using one loop. 1, 2, 3, 4, 5 6, 7, 8, 9, 10 Try to achieve the result by forcing the next iteration within the loop upon a specific condition, if your language allows it. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Erlang
Erlang
%% Implemented by Arjun Sunel -module(continue). -export([main/0, for_loop/1]).   main() -> for_loop(1).   for_loop(N) when N /= 5 , N <10 -> io:format("~p, ",[N] ), for_loop(N+1);   for_loop(N) when N >=10-> if N=:=10 -> io:format("~p\n",[N] ) end;   for_loop(N) -> if N=:=5 -> io:format("~p\n",[N] ), for_loop(N+1) end.  
http://rosettacode.org/wiki/Longest_common_substring
Longest common substring
Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are consecutive characters within a string.   This distinguishes them from subsequences, which is any sequence of characters within a string, even if there are extraneous characters in between them. Hence, the longest common subsequence between "thisisatest" and "testing123testing" is "tsitest", whereas the longest common substring is just "test". Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet References Generalize Suffix Tree Ukkonen’s Suffix Tree Construction
#JavaScript
JavaScript
(() => { 'use strict';   // longestCommon :: String -> String -> String const longestCommon = (s1, s2) => maximumBy( comparing(length), intersect(...apList( [s => map( concat, concatMap(tails, compose(tail, inits)(s)) )], [s1, s2] )) );   // main :: IO () const main = () => console.log( longestCommon( "testing123testing", "thisisatest" ) );   // GENERIC FUNCTIONS ----------------------------   // Each member of a list of functions applied to each // of a list of arguments, deriving a list of new values.   // apList (<*>) :: [(a -> b)] -> [a] -> [b] const apList = (fs, xs) => // fs.reduce((a, f) => a.concat( xs.reduce((a, x) => a.concat([f(x)]), []) ), []);   // comparing :: (a -> b) -> (a -> a -> Ordering) const comparing = f => (x, y) => { const a = f(x), b = f(y); return a < b ? -1 : (a > b ? 1 : 0); };   // compose (<<<) :: (b -> c) -> (a -> b) -> a -> c const compose = (f, g) => x => f(g(x));   // concat :: [[a]] -> [a] // concat :: [String] -> String const concat = xs => 0 < xs.length ? (() => { const unit = 'string' !== typeof xs[0] ? ( [] ) : ''; return unit.concat.apply(unit, xs); })() : [];   // concatMap :: (a -> [b]) -> [a] -> [b] const concatMap = (f, xs) => xs.reduce((a, x) => a.concat(f(x)), []);   // inits([1, 2, 3]) -> [[], [1], [1, 2], [1, 2, 3] // inits('abc') -> ["", "a", "ab", "abc"]   // inits :: [a] -> [[a]] // inits :: String -> [String] const inits = xs => [ [] ] .concat(('string' === typeof xs ? xs.split('') : xs) .map((_, i, lst) => lst.slice(0, i + 1)));   // intersect :: (Eq a) => [a] -> [a] -> [a] const intersect = (xs, ys) => xs.filter(x => -1 !== ys.indexOf(x));   // Returns Infinity over objects without finite length. // This enables zip and zipWith to choose the shorter // argument when one is non-finite, like cycle, repeat etc   // length :: [a] -> Int const length = xs => (Array.isArray(xs) || 'string' === typeof xs) ? ( xs.length ) : Infinity;   // map :: (a -> b) -> [a] -> [b] const map = (f, xs) => xs.map(f);   // maximumBy :: (a -> a -> Ordering) -> [a] -> a const maximumBy = (f, xs) => 0 < xs.length ? ( xs.slice(1) .reduce((a, x) => 0 < f(x, a) ? x : a, xs[0]) ) : undefined;   // tail :: [a] -> [a] const tail = xs => 0 < xs.length ? xs.slice(1) : [];   // tails :: [a] -> [[a]] const tails = xs => { const es = ('string' === typeof xs) ? ( xs.split('') ) : xs; return es.map((_, i) => es.slice(i)) .concat([ [] ]); };   // MAIN --- return main(); })();
http://rosettacode.org/wiki/Loops/Nested
Loops/Nested
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over [ 1 , … , 20 ] {\displaystyle [1,\ldots ,20]} . The loops iterate rows and columns of the array printing the elements until the value 20 {\displaystyle 20} is met. Specifically, this task also shows how to break out of nested loops. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Stata
Stata
matrix a=J(20,20,0) forv i=1/20 { forv j=1/20 { matrix a[`i',`j']=runiformint(1,20) } }
http://rosettacode.org/wiki/Loops/Nested
Loops/Nested
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over [ 1 , … , 20 ] {\displaystyle [1,\ldots ,20]} . The loops iterate rows and columns of the array printing the elements until the value 20 {\displaystyle 20} is met. Specifically, this task also shows how to break out of nested loops. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Swift
Swift
let array = [[2, 12, 10, 4], [18, 11, 20, 2]]   loop: for row in array { for element in row { println(" \(element)") if element == 20 { break loop } } } print("done")
http://rosettacode.org/wiki/Loops/Foreach
Loops/Foreach
Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#zig
zig
const warn = @import("std").debug.warn;   pub fn main() void { const items = [_]i16{ 0, 1, 1, 2, 3, 5, 8 };   for (items) |i| { warn("{}\n", .{i}); } }  
http://rosettacode.org/wiki/Loops/Foreach
Loops/Foreach
Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#zkl
zkl
foreach c in (T("Red","Green","Blue","Black","White")) { print(c," "); }
http://rosettacode.org/wiki/Loops/Foreach
Loops/Foreach
Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Zig_2
Zig
const std = @import("std");   pub fn main() !void { const stdout_wr = std.io.getStdOut().writer();   // 1. Index element index sizes are comptime-known const a1: []const u8 = &[_]u8{ 'a', 'b', 'c' }; // also works with slices //const a2: [] u8 = &a1; for (a1) |el_a| try stdout_wr.print("{c}\n", .{el_a}); // 2. Index element index sizes are not comptime-known // Convention is to provide a `next()` method. // TODO }
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers
Luhn test of credit card numbers
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of the digits in the number. Take the first, third, ... and every other odd digit in the reversed digits and sum them to form the partial sum s1 Taking the second, fourth ... and every other even digit in the reversed digits: Multiply each digit by two and sum the digits if the answer is greater than nine to form partial sums for the even digits Sum the partial sums of the even digits to form s2 If s1 + s2 ends in zero then the original number is in the form of a valid credit card number as verified by the Luhn test. For example, if the trial number is 49927398716: Reverse the digits: 61789372994 Sum the odd digits: 6 + 7 + 9 + 7 + 9 + 4 = 42 = s1 The even digits: 1, 8, 3, 2, 9 Two times each even digit: 2, 16, 6, 4, 18 Sum the digits of each multiplication: 2, 7, 6, 4, 9 Sum the last: 2 + 7 + 6 + 4 + 9 = 28 = s2 s1 + s2 = 70 which ends in zero which means that 49927398716 passes the Luhn test Task Write a function/method/procedure/subroutine that will validate a number with the Luhn test, and use it to validate the following numbers: 49927398716 49927398717 1234567812345678 1234567812345670 Related tasks   SEDOL   ISIN
#Phix
Phix
with javascript_semantics function Luhn(string st) integer s=0, d for i=1 to length(st) do d = st[-i]-'0' s += iff(mod(i,2)?d,d*2-(d>4)*9) end for return remainder(s,10)=0 end function procedure test(string s) printf(1,"%20s : %t\n",{s,Luhn(s)}) end procedure papply({"49927398716","49927398717","1234567812345678","1234567812345670"},test)
http://rosettacode.org/wiki/Loops/Infinite
Loops/Infinite
Task Print out       SPAM       followed by a   newline   in an infinite loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#R
R
repeat print("SPAM")
http://rosettacode.org/wiki/Loops/Infinite
Loops/Infinite
Task Print out       SPAM       followed by a   newline   in an infinite loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Racket
Racket
  #lang racket   ;; Using recursion (define (loop) (displayln "SPAM") (loop))   (loop)   ;; Using a for loop (for ([i (in-naturals)]) (displayln "SPAM"))  
http://rosettacode.org/wiki/Loops/While
Loops/While
Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreachbas   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#PHP
PHP
$i = 1024; while ($i > 0) { echo "$i\n"; $i >>= 1; }
http://rosettacode.org/wiki/Loops/While
Loops/While
Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreachbas   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Picat
Picat
go => N = 1024, while (N > 0) println(N), N := N // 2 end.
http://rosettacode.org/wiki/Loops/Downward_for
Loops/Downward for
Task Write a   for   loop which writes a countdown from   10   to   0. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Raku
Raku
for 10 ... 0 { .say; }
http://rosettacode.org/wiki/Loops/Downward_for
Loops/Downward for
Task Write a   for   loop which writes a countdown from   10   to   0. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#REBOL
REBOL
for i 10 0 -1 [print i]
http://rosettacode.org/wiki/Loops/Do-while
Loops/Do-while
Start with a value at 0. Loop while value mod 6 is not equal to 0. Each time through the loop, add 1 to the value then print it. The loop must execute at least once. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges Reference Do while loop Wikipedia.
#.D0.9C.D0.9A-61.2F52
МК-61/52
0 П4 КИП4 ИП4 6 / {x} x=0 02 С/П
http://rosettacode.org/wiki/Loops/Do-while
Loops/Do-while
Start with a value at 0. Loop while value mod 6 is not equal to 0. Each time through the loop, add 1 to the value then print it. The loop must execute at least once. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges Reference Do while loop Wikipedia.
#Modula-2
Modula-2
MODULE DoWhile; IMPORT InOut;   VAR i: INTEGER;   BEGIN i := 0; REPEAT INC(i); InOut.WriteInt(i, 1); InOut.WriteLn; UNTIL i MOD 6 = 0; END DoWhile.
http://rosettacode.org/wiki/Loops/For
Loops/For
“For”   loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code. Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers. Task Show how two loops may be nested within each other, with the number of iterations performed by the inner for loop being controlled by the outer for loop. Specifically print out the following pattern by using one for loop nested in another: * ** *** **** ***** Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges Reference For loop Wikipedia.
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   For i As Integer = 1 To 5 For j As Integer = 1 To i Print "*"; Next Print Next   Sleep
http://rosettacode.org/wiki/Loops/For_with_a_specified_step
Loops/For with a specified step
Task Demonstrate a   for-loop   where the step-value is greater than one. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#M2000_Interpreter
M2000 Interpreter
  Module LoopFor { Locale 1036 Document doc$ \\ define i as a single def single i for i=1 to 21 step 5/3 Print i doc$=format$(" {0}", i) next i doc$={ } \\ make i as a single for i=21 to 1 step 5/3 Print i doc$=format$(" {0}", i) next i clipboard doc$ report doc$ } LoopFor  
http://rosettacode.org/wiki/Long_multiplication
Long multiplication
Task Explicitly implement   long multiplication. This is one possible approach to arbitrary-precision integer algebra. For output, display the result of   264 * 264. Optionally, verify your result against builtin arbitrary precision support. The decimal representation of   264   is: 18,446,744,073,709,551,616 The output of   264 * 264   is   2128,   and is: 340,282,366,920,938,463,463,374,607,431,768,211,456
#Arturo
Arturo
print 2^64 * 2
http://rosettacode.org/wiki/Literals/String
Literals/String
Task Show literal specification of characters and strings. If supported, show how the following work:   verbatim strings   (quotes where escape sequences are quoted literally)   here-strings   Also, discuss which quotes expand variables. Related tasks   Special characters   Here document Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#AWK
AWK
c = "x" str= "hello" s1 = "abcd" # simple string s2 = "ab\"cd" # string containing a double quote, escaped with backslash print s1 print s2
http://rosettacode.org/wiki/Literals/String
Literals/String
Task Show literal specification of characters and strings. If supported, show how the following work:   verbatim strings   (quotes where escape sequences are quoted literally)   here-strings   Also, discuss which quotes expand variables. Related tasks   Special characters   Here document Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Axe
Axe
'A'
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Lua
Lua
revised = "February 2, 2021" -- the long literal string is delimited by double square brackets: [[...]] -- each word must be separated by at least one whitespace character -- additional whitespace may optionally be used to improve readability -- (starting column does not matter, clause length is more than adequate) longliteral = [[ hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminum silicon phosphorous sulfur chlorine argon potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon cesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson ]] -- the task requires the "final list" as single-space-between string version -- (a more idiomatic overall approach would be to directly split into a table) finallist = longliteral:gsub("%s+"," ")   elements = {} -- longliteral could be used here DIRECTLY instead of using finallist: for name in finallist:gmatch("%w+") do elements[#elements+1]=name end print("revised date: " .. revised) print("# elements  : " .. #elements) print("last element: " .. elements[#elements])   -- then, if still required, produce a single-space-between string version: --finallist = table.concat(elements," ")
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Nim
Nim
import strutils   const RevDate = "2021-02-05"   # We use the concatenation operator "&" to assemble the strings. # This is done at compile time and so the result is a long literal. const ElementString = "hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine " & "neon sodium magnesium aluminum silicon phosphorous sulfur chlorine argon " & "potassium calcium scandium titanium vanadium chromium manganese iron " & "cobalt nickel copper zinc gallium germanium arsenic selenium bromine " & "krypton rubidium strontium yttrium zirconium niobium molybdenum " & "technetium ruthenium rhodium palladium silver cadmium indium tin " & "antimony tellurium iodine xenon cesium barium lanthanum cerium " & "praseodymium neodymium promethium samarium europium gadolinium terbium " & "dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum " & "tungsten rhenium osmium iridium platinum gold mercury thallium lead " & "bismuth polonium astatine radon francium radium actinium thorium " & "protactinium uranium neptunium plutonium americium curium berkelium " & "californium einsteinium fermium mendelevium nobelium lawrencium " & "rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium " & "roentgenium copernicium nihonium flerovium moscovium livermorium " & "tennessine oganesson"   when isMainModule:   const ElementList = ElementString.split()   echo "Last revision date: ", RevDate echo "Number of elements: ", ElementList.len echo "Last element in list: ", ElementList[^1]
http://rosettacode.org/wiki/Long_literals,_with_continuations
Long literals, with continuations
This task is about writing a computer program that has long literals   (character literals that may require specifying the words/tokens on more than one (source) line,   either with continuations or some other method, such as abutments or concatenations   (or some other mechanisms). The literal is to be in the form of a "list",   a literal that contains many words (tokens) separated by a blank (space),   in this case   (so as to have a common list),   the (English) names of the chemical elements of the periodic table. The list is to be in (ascending) order of the (chemical) element's atomic number: hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium aluminum silicon ... ... up to the last known (named) chemical element   (at this time). Do not include any of the   "unnamed"   chemical element names such as: ununennium unquadnilium triunhexium penthextrium penthexpentium septhexunium octenntrium ennennbium To make computer programming languages comparable,   the statement widths should be restricted to less than   81   bytes (characters),   or less if a computer programming language has more restrictive limitations or standards. Also mention what column the programming statements can start in if   not   in column one. The list   may   have leading/embedded/trailing blanks during the declaration   (the actual program statements),   this is allow the list to be more readable.   The "final" list shouldn't have any leading/trailing or superfluous blanks   (when stored in the program's "memory"). This list should be written with the idea in mind that the program   will   be updated,   most likely someone other than the original author,   as there will be newer (discovered) elements of the periodic table being added   (possibly in the near future).   These future updates should be one of the primary concerns in writing these programs and it should be "easy" for someone else to add chemical elements to the list   (within the computer program). Attention should be paid so as to not exceed the   clause length   of continued or specified statements,   if there is such a restriction.   If the limit is greater than (say) 4,000 bytes or so,   it needn't be mentioned here. Task   Write a computer program (by whatever name) to contain a list of the known elements.   The program should eventually contain a long literal of words   (the elements).   The literal should show how one could create a long list of blank-delineated words.   The "final" (stored) list should only have a single blank between elements.   Try to use the most idiomatic approach(es) in creating the final list.   Use continuation if possible, and/or show alternatives   (possibly using concatenation).   Use a program comment to explain what the continuation character is if it isn't obvious.   The program should contain a variable that has the date of the last update/revision.   The program, when run, should display with verbiage:   The last update/revision date   (and should be unambiguous).   The number of chemical elements in the list.   The name of the highest (last) element name. Show all output here, on this page. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Pascal
Pascal
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Long_literals,_with_continuations use warnings;   my $longliteral = join ' ', split ' ', <<END; hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminum silicon phosphorous sulfur chlorine argon potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon cesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson END   my $version = 'Tue Feb 2 22:30:48 UTC 2021'; my $count = my @elements = split ' ', $longliteral; my $last = $elements[-1];   print <<END; version: $version element count: $count last element: $last END
http://rosettacode.org/wiki/List_rooted_trees
List rooted trees
You came back from grocery shopping.   After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink.   In doing so, you realize that there are various ways of nesting the bags, with all bags viewed as identical. If we use a matching pair of parentheses to represent a bag, the ways are: For 1 bag, there's one way: () <- a bag for 2 bags, there's one way: (()) <- one bag in another for 3 bags, there are two: ((())) <- 3 bags nested Russian doll style (()()) <- 2 bags side by side, inside the third for 4 bags, four: (()()()) ((())()) ((()())) (((()))) Note that because all bags are identical, the two 4-bag strings ((())()) and (()(())) represent the same configuration. It's easy to see that each configuration for n bags represents a n-node rooted tree, where a bag is a tree node, and a bag with its content forms a subtree. The outermost bag is the tree root. Number of configurations for given n is given by OEIS A81. Task Write a program that, when given n, enumerates all ways of nesting n bags.   You can use the parentheses notation above, or any tree representation that's unambiguous and preferably intuitive. This task asks for enumeration of trees only; for counting solutions without enumeration, that OEIS page lists various formulas, but that's not encouraged by this task, especially if implementing it would significantly increase code size. As an example output, run 5 bags.   There should be 9 ways.
#J
J
root=: 1 1 $ _ incr=: ,/@(,"1 0/ i.@{:@$)   boxed=: $:&0 :(<@\:~@([ $:^:(0 < #@]) I.@:=))"1 1 0
http://rosettacode.org/wiki/List_rooted_trees
List rooted trees
You came back from grocery shopping.   After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink.   In doing so, you realize that there are various ways of nesting the bags, with all bags viewed as identical. If we use a matching pair of parentheses to represent a bag, the ways are: For 1 bag, there's one way: () <- a bag for 2 bags, there's one way: (()) <- one bag in another for 3 bags, there are two: ((())) <- 3 bags nested Russian doll style (()()) <- 2 bags side by side, inside the third for 4 bags, four: (()()()) ((())()) ((()())) (((()))) Note that because all bags are identical, the two 4-bag strings ((())()) and (()(())) represent the same configuration. It's easy to see that each configuration for n bags represents a n-node rooted tree, where a bag is a tree node, and a bag with its content forms a subtree. The outermost bag is the tree root. Number of configurations for given n is given by OEIS A81. Task Write a program that, when given n, enumerates all ways of nesting n bags.   You can use the parentheses notation above, or any tree representation that's unambiguous and preferably intuitive. This task asks for enumeration of trees only; for counting solutions without enumeration, that OEIS page lists various formulas, but that's not encouraged by this task, especially if implementing it would significantly increase code size. As an example output, run 5 bags.   There should be 9 ways.
#Java
Java
import java.util.ArrayList; import java.util.List;   public class ListRootedTrees { private static final List<Long> TREE_LIST = new ArrayList<>();   private static final List<Integer> OFFSET = new ArrayList<>();   static { for (int i = 0; i < 32; i++) { if (i == 1) { OFFSET.add(1); } else { OFFSET.add(0); } } }   private static void append(long t) { TREE_LIST.add(1 | (t << 1)); }   private static void show(long t, int l) { while (l-- > 0) { if (t % 2 == 1) { System.out.print('('); } else { System.out.print(')'); } t = t >> 1; } }   private static void listTrees(int n) { for (int i = OFFSET.get(n); i < OFFSET.get(n + 1); i++) { show(TREE_LIST.get(i), n * 2); System.out.println(); } }   private static void assemble(int n, long t, int sl, int pos, int rem) { if (rem == 0) { append(t); return; }   var pp = pos; var ss = sl;   if (sl > rem) { ss = rem; pp = OFFSET.get(ss); } else if (pp >= OFFSET.get(ss + 1)) { ss--; if (ss == 0) { return; } pp = OFFSET.get(ss); }   assemble(n, t << (2 * ss) | TREE_LIST.get(pp), ss, pp, rem - ss); assemble(n, t, ss, pp + 1, rem); }   private static void makeTrees(int n) { if (OFFSET.get(n + 1) != 0) { return; } if (n > 0) { makeTrees(n - 1); } assemble(n, 0, n - 1, OFFSET.get(n - 1), n - 1); OFFSET.set(n + 1, TREE_LIST.size()); }   private static void test(int n) { if (n < 1 || n > 12) { throw new IllegalArgumentException("Argument must be between 1 and 12"); }   append(0);   makeTrees(n); System.out.printf("Number of %d-trees: %d\n", n, OFFSET.get(n + 1) - OFFSET.get(n)); listTrees(n); }   public static void main(String[] args) { test(5); } }
http://rosettacode.org/wiki/Literals/Integer
Literals/Integer
Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be interpreted by the compiler or interpreter as an integer written to a given base. Also show any other ways of expressing literals, e.g. for different types of integers. Related task   Literals/Floating point
#Avail
Avail
Print: "0b11001101 = " ++ “0b11001101”; Print: "0o755 = " ++ “0o755”; Print: "0xDEADBEEF = " ++ “0xDEADBEEF”;
http://rosettacode.org/wiki/Literals/Integer
Literals/Integer
Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be interpreted by the compiler or interpreter as an integer written to a given base. Also show any other ways of expressing literals, e.g. for different types of integers. Related task   Literals/Floating point
#AWK
AWK
BEGIN { if ( (0x2d7 == 727) && (01327 == 727) ) { print "true with GNU awk" } }
http://rosettacode.org/wiki/Logical_operations
Logical operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation | Comparison | Matching Memory Operations Pointers & references | Addresses Task Write a function that takes two logical (boolean) values, and outputs the result of "and" and "or" on both arguments as well as "not" on the first arguments. If the programming language doesn't provide a separate type for logical values, use the type most commonly used for that purpose. If the language supports additional logical operations on booleans such as XOR, list them as well.
#ALGOL_68
ALGOL 68
PROC print_logic = (BOOL a, b)VOID: ( # for a 6-7 bit/byte compiler # printf(($"a and b is "gl$, a AND b); printf(($"a or b is "gl$, a OR b); printf(($"not a is "gl$, NOT a); printf(($"a equivalent to b is "gl$, a EQ b); printf(($"a not equivalent to b is "gl$, a NE b);   # Alternatively ASCII # printf(($"a and b is "gl$, a & b); printf(($"a and b is "gl$, a /\ b); <!-- http://web.archive.org/web/20021207211127/http://www.bobbemer.com/BRACES.HTM --> printf(($"a or b is "gl$, a \/ b); printf(($"a equivalent to b "gl$, a = b); printf(($"a not equivalent to b "gl$, a /= b);   ¢ for a European 8 bit/byte charcter set eg. ALCOR or GOST ¢ printf(($"a and b is "gl$, a ∧ b); printf(($"a or b is "gl$, a ∨ b); printf(($"not a is "gl$, ¬ a) printf(($"a not equivalent to b is "gl$, a ≠ b) )
http://rosettacode.org/wiki/Loops/N_plus_one_half
Loops/N plus one half
Quite often one needs loops which, in the last iteration, execute only part of the loop body. Goal Demonstrate the best way to do this. Task Write a loop which writes the comma-separated list 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 using separate output statements for the number and the comma from within the body of the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#Ursa
Ursa
decl int i for (set i 1) (< i 11) (inc i) out i console if (= i 10) break end if out ", " console end for out endl console
http://rosettacode.org/wiki/Loops/N_plus_one_half
Loops/N plus one half
Quite often one needs loops which, in the last iteration, execute only part of the loop body. Goal Demonstrate the best way to do this. Task Write a loop which writes the comma-separated list 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 using separate output statements for the number and the comma from within the body of the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#V
V
[loop [ [10 =] [puts] [true] [dup put ',' put succ loop] ] when].
http://rosettacode.org/wiki/Literals/Floating_point
Literals/Floating point
Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF/ABNF/EBNF defining allowable formats for your language. Related tasks   Literals/Integer   Extreme floating point values
#Erlang
Erlang
  printf(1,"Exponential:\t%e, %e, %e, %e\n",{-10.1246,10.2356,16.123456789,64.12}) printf(1,"Floating Point\t%03.3f, %04.3f, %+3.3f, %3.3f\n",{-10.1246,10.2356,16.123456789,64.12}) printf(1,"Floating Point or Exponential:  %g, %g, %g, %g\n",{10,16.123456789,64,123456789.123})  
http://rosettacode.org/wiki/Literals/Floating_point
Literals/Floating point
Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF/ABNF/EBNF defining allowable formats for your language. Related tasks   Literals/Integer   Extreme floating point values
#Euphoria
Euphoria
  printf(1,"Exponential:\t%e, %e, %e, %e\n",{-10.1246,10.2356,16.123456789,64.12}) printf(1,"Floating Point\t%03.3f, %04.3f, %+3.3f, %3.3f\n",{-10.1246,10.2356,16.123456789,64.12}) printf(1,"Floating Point or Exponential:  %g, %g, %g, %g\n",{10,16.123456789,64,123456789.123})  
http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#Haskell
Haskell
import Data.Time.Calendar (fromGregorian) import Data.Time.Calendar.WeekDate (toWeekDate)   longYear :: Integer -> Bool longYear y = let (_, w, _) = toWeekDate $ fromGregorian y 12 28 in 52 < w   main :: IO () main = mapM_ print $ filter longYear [2000 .. 2100]
http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#J
J
p =: 1 4 _100 400&(7 | [: <. +/ @: %~)"1 0 ily =: (4=p) +. 3=p@:<: ply =: (#~ ily)@:([ + 1+i.@:-~)
http://rosettacode.org/wiki/Long_primes
Long primes
A   long prime   (as defined here)   is a prime number whose reciprocal   (in decimal)   has a   period length   of one less than the prime number. Long primes   are also known as:   base ten cyclic numbers   full reptend primes   golden primes   long period primes   maximal period primes   proper primes Another definition:   primes   p   such that the decimal expansion of   1/p   has period   p-1,   which is the greatest period possible for any integer. Example 7   is the first long prime,   the reciprocal of seven is   1/7,   which is equal to the repeating decimal fraction   0.142857142857··· The length of the   repeating   part of the decimal fraction is six,   (the underlined part)   which is one less than the (decimal) prime number   7. Thus   7   is a long prime. There are other (more) general definitions of a   long prime   which include wording/verbiage for bases other than ten. Task   Show all long primes up to   500   (preferably on one line).   Show the   number   of long primes up to        500   Show the   number   of long primes up to     1,000   Show the   number   of long primes up to     2,000   Show the   number   of long primes up to     4,000   Show the   number   of long primes up to     8,000   Show the   number   of long primes up to   16,000   Show the   number   of long primes up to   32,000   Show the   number   of long primes up to   64,000   (optional)   Show all output here. Also see   Wikipedia: full reptend prime   MathWorld: full reptend prime   OEIS: A001913
#Go
Go
package main   import "fmt"   func sieve(limit int) []int { var primes []int c := make([]bool, limit + 1) // composite = true // no need to process even numbers p := 3 p2 := p * p for p2 <= limit { for i := p2; i <= limit; i += 2 * p { c[i] = true } for ok := true; ok; ok = c[p] { p += 2 } p2 = p * p } for i := 3; i <= limit; i += 2 { if !c[i] { primes = append(primes, i) } } return primes }   // finds the period of the reciprocal of n func findPeriod(n int) int { r := 1 for i := 1; i <= n + 1; i++ { r = (10 * r) % n } rr := r period := 0 for ok := true; ok; ok = r != rr { r = (10 * r) % n period++ } return period }   func main() { primes := sieve(64000) var longPrimes []int for _, prime := range primes { if findPeriod(prime) == prime - 1 { longPrimes = append(longPrimes, prime) } } numbers := []int{500, 1000, 2000, 4000, 8000, 16000, 32000, 64000} index := 0 count := 0 totals := make([]int, len(numbers)) for _, longPrime := range longPrimes { if longPrime > numbers[index] { totals[index] = count index++ } count++ } totals[len(numbers)-1] = count fmt.Println("The long primes up to", numbers[0], "are: ") fmt.Println(longPrimes[:totals[0]])   fmt.Println("\nThe number of long primes up to: ") for i, total := range totals { fmt.Printf("  %5d is %d\n", numbers[i], total) } }
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously
Loop over multiple arrays simultaneously
Task Loop over multiple arrays   (or lists or tuples or whatever they're called in your language)   and display the   i th   element of each. Use your language's   "for each"   loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: (a,b,c) (A,B,C) (1,2,3) to produce the output: aA1 bB2 cC3 If possible, also describe what happens when the arrays are of different lengths. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges   Loops/Wrong ranges
#BBC_BASIC
BBC BASIC
DIM array1$(2), array2$(2), array3%(2) array1$() = "a", "b", "c" array2$() = "A", "B", "C" array3%() = 1, 2, 3   FOR index% = 0 TO 2 PRINT array1$(index%) ; array2$(index%) ; array3%(index%) NEXT
http://rosettacode.org/wiki/Loops/Break
Loops/Break
Task Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive). If a number is 10, stop the loop after printing it, and do not generate any further numbers. Otherwise, generate and print a second random number before restarting the loop. If the number 10 is never generated as the first number in a loop, loop forever. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop body   Loops/Infinite   Loops/N plus one half   Loops/Nested   Loops/While   Loops/with multiple ranges
#Clojure
Clojure
(loop [[a b & more] (repeatedly #(rand-int 20))] (println a) (when-not (= 10 a) (println b) (recur more)))
http://rosettacode.org/wiki/Longest_common_subsequence
Longest common subsequence
Introduction Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string. The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings. Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be strings drawn from an alphabet Σ of size s, containing every distinct symbol in A + B. An ordered pair (i, j) will be referred to as a match if A[i] = B[j], where 0 < i ≤ m and 0 < j ≤ n. Define a non-strict product-order (≤) over ordered pairs, such that (i1, j1) ≤ (i2, j2) ⇔ i1 ≤ i2 and j1 ≤ j2. We define (≥) similarly. We say m1, m2 are comparable if either m1 ≤ m2 or m1 ≥ m2 holds. If i1 < i2 and j2 < j1 (or i2 < i1 and j1 < j2) then neither m1 ≤ m2 nor m1 ≥ m2 are possible; and we say m1, m2 are incomparable. We also define the strict product-order (<) over ordered pairs, such that (i1, j1) < (i2, j2) ⇔ i1 < i2 and j1 < j2. We define (>) similarly. Given a set of matches M, a chain C is a subset of M consisting of at least one element m; and where either m1 < m2 or m1 > m2 for every pair of distinct elements m1 and m2. An antichain D is any subset of M in which every pair of distinct elements m1 and m2 are incomparable. The set M represents a relation over match pairs: M[i, j] ⇔ (i, j) ∈ M. A chain C can be visualized as a curve which strictly increases as it passes through each match pair in the m*n coordinate space. Finding an LCS can be restated as the problem of finding a chain of maximum cardinality p over the set of matches M. According to [Dilworth 1950], this cardinality p equals the minimum number of disjoint antichains into which M can be decomposed. Note that such a decomposition into the minimal number p of disjoint antichains may not be unique. Contours Forward Contours FC[k] of class k are defined inductively, as follows: FC[0] consists of those elements m1 for which there exists no element m2 such that m2 < m1. FC[k] consists of those elements m1 for which there exists no element m2 such that m2 < m1; and where neither m1 nor m2 are contained in FC[l] for any class l < k. Reverse Contours RC[k] of class k are defined similarly. Members of the Meet (∧), or Infimum of a Forward Contour are referred to as its Dominant Matches: those m1 for which there exists no m2 such that m2 < m1. Members of the Join (∨), or Supremum of a Reverse Contour are referred to as its Dominant Matches: those m1 for which there exists no m2 such that m2 > m1. Where multiple Dominant Matches exist within a Meet (or within a Join, respectively) the Dominant Matches will be incomparable to each other. Background Where the number of symbols appearing in matches is small relative to the length of the input strings, reuse of the symbols increases; and the number of matches will tend towards quadratic, O(m*n) growth. This occurs, for example, in the Bioinformatics application of nucleotide and protein sequencing. The divide-and-conquer approach of [Hirschberg 1975] limits the space required to O(n). However, this approach requires O(m*n) time even in the best case. This quadratic time dependency may become prohibitive, given very long input strings. Thus, heuristics are often favored over optimal Dynamic Programming solutions. In the application of comparing file revisions, records from the input files form a large symbol space; and the number of symbols approaches the length of the LCS. In this case the number of matches reduces to linear, O(n) growth. A binary search optimization due to [Hunt and Szymanski 1977] can be applied to the basic Dynamic Programming approach, resulting in an expected performance of O(n log m). Performance can degrade to O(m*n log m) time in the worst case, as the number of matches grows to O(m*n). Note [Rick 2000] describes a linear-space algorithm with a time bound of O(n*s + p*min(m, n - p)). Legend A, B are input strings of lengths m, n respectively p is the length of the LCS M is the set of match pairs (i, j) such that A[i] = B[j] r is the magnitude of M s is the magnitude of the alphabet Σ of distinct symbols in A + B References [Dilworth 1950] "A decomposition theorem for partially ordered sets" by Robert P. Dilworth, published January 1950, Annals of Mathematics [Volume 51, Number 1, pp. 161-166] [Goeman and Clausen 2002] "A New Practical Linear Space Algorithm for the Longest Common Subsequence Problem" by Heiko Goeman and Michael Clausen, published 2002, Kybernetika [Volume 38, Issue 1, pp. 45-66] [Hirschberg 1975] "A linear space algorithm for computing maximal common subsequences" by Daniel S. Hirschberg, published June 1975 Communications of the ACM [Volume 18, Number 6, pp. 341-343] [Hunt and McIlroy 1976] "An Algorithm for Differential File Comparison" by James W. Hunt and M. Douglas McIlroy, June 1976 Computing Science Technical Report, Bell Laboratories 41 [Hunt and Szymanski 1977] "A Fast Algorithm for Computing Longest Common Subsequences" by James W. Hunt and Thomas G. Szymanski, published May 1977 Communications of the ACM [Volume 20, Number 5, pp. 350-353] [Rick 2000] "Simple and fast linear space computation of longest common subsequences" by Claus Rick, received 17 March 2000, Information Processing Letters, Elsevier Science [Volume 75, pp. 275–281] Examples The sequences "1234" and "1224533324" have an LCS of "1234": 1234 1224533324 For a string example, consider the sequences "thisisatest" and "testing123testing". An LCS would be "tsitest": thisisatest testing123testing In this puzzle, your code only needs to deal with strings. Write a function which returns an LCS of two strings (case-sensitive). You don't need to show multiple LCS's. For more information on this problem please see Wikipedia. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#D
D
import std.stdio, std.array;   T[] lcs(T)(in T[] a, in T[] b) pure nothrow @safe { if (a.empty || b.empty) return null; if (a[0] == b[0]) return a[0] ~ lcs(a[1 .. $], b[1 .. $]); const longest = (T[] x, T[] y) => x.length > y.length ? x : y; return longest(lcs(a, b[1 .. $]), lcs(a[1 .. $], b)); }   void main() { lcs("thisisatest", "testing123testing").writeln; }
http://rosettacode.org/wiki/Look-and-say_sequence
Look-and-say sequence
The   Look and say sequence   is a recursively defined sequence of numbers studied most notably by   John Conway. The   look-and-say sequence   is also known as the   Morris Number Sequence,   after cryptographer Robert Morris,   and the puzzle   What is the next number in the sequence 1,   11,   21,   1211,   111221?   is sometimes referred to as the Cuckoo's Egg,   from a description of Morris in Clifford Stoll's book   The Cuckoo's Egg. Sequence Definition Take a decimal number Look at the number, visually grouping consecutive runs of the same digit. Say the number, from left to right, group by group; as how many of that digit there are - followed by the digit grouped. This becomes the next number of the sequence. An example: Starting with the number 1,   you have one 1 which produces 11 Starting with 11,   you have two 1's.   I.E.:   21 Starting with 21,   you have one 2, then one 1.   I.E.:   (12)(11) which becomes 1211 Starting with 1211,   you have one 1, one 2, then two 1's.   I.E.:   (11)(12)(21) which becomes 111221 Task Write a program to generate successive members of the look-and-say sequence. Related tasks   Fours is the number of letters in the ...   Number names   Self-describing numbers   Self-referential sequence   Spelling of ordinal numbers See also   Look-and-Say Numbers (feat John Conway), A Numberphile Video.   This task is related to, and an application of, the Run-length encoding task.   Sequence A005150 on The On-Line Encyclopedia of Integer Sequences.
#Bracmat
Bracmat
( 1:?number & 0:?lines & whl ' ( 1+!lines:~>10:?lines & :?say { This will accumulate all that has to be said after one iteration. } & 0:?begin & ( @( !number { Pattern matching. The '@' indicates we're looking in a string rather than a tree structure. }  :  ? ( [!begin  %@?digit  ? [?end ( (|(%@:~!digit) ?) { The %@ guarantees we're testing one character - not less (%) and not more (@). The ? takes the rest. } & !say !end+-1*!begin !digit:?say & !end:?begin { When backtracking, 'begin' advances to the begin of the next sequence, or to the end of the string. } ) & ~ { fail! This forces backtracking. Backtracking stops when all begin positions have been tried. } ) ) | out$(str$!say:?number) { After backtracking, output string and set number to string for next iteration. } ) ) );
http://rosettacode.org/wiki/Longest_string_challenge
Longest string challenge
Background This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the challenge and fun part came through the introduction of restrictions. Experience has shown that the original restrictions required some adjustment to bring out the intent of the challenge and make it suitable for Rosetta Code. Basic problem statement Write a program that reads lines from standard input and, upon end of file, writes the longest line to standard output. If there are ties for the longest line, the program writes out all the lines that tie. If there is no input, the program should produce no output. Task Implement a solution to the basic problem that adheres to the spirit of the restrictions (see below). Describe how you circumvented or got around these 'restrictions' and met the 'spirit' of the challenge. Your supporting description may need to describe any challenges to interpreting the restrictions and how you made this interpretation. You should state any assumptions, warnings, or other relevant points. The central idea here is to make the task a bit more interesting by thinking outside of the box and perhaps by showing off the capabilities of your language in a creative way. Because there is potential for considerable variation between solutions, the description is key to helping others see what you've done. This task is likely to encourage a variety of different types of solutions. They should be substantially different approaches. Given the input: a bb ccc ddd ee f ggg the output should be (possibly rearranged): ccc ddd ggg Original list of restrictions No comparison operators may be used. No arithmetic operations, such as addition and subtraction, may be used. The only datatypes you may use are integer and string. In particular, you may not use lists. Do not re-read the input file. Avoid using files as a replacement for lists (this restriction became apparent in the discussion). Intent of restrictions Because of the variety of languages on Rosetta Code and the wide variety of concepts used in them, there needs to be a bit of clarification and guidance here to get to the spirit of the challenge and the intent of the restrictions. The basic problem can be solved very conventionally, but that's boring and pedestrian. The original intent here wasn't to unduly frustrate people with interpreting the restrictions, it was to get people to think outside of their particular box and have a bit of fun doing it. The guiding principle here should be to be creative in demonstrating some of the capabilities of the programming language being used. If you need to bend the restrictions a bit, explain why and try to follow the intent. If you think you've implemented a 'cheat', call out the fragment yourself and ask readers if they can spot why. If you absolutely can't get around one of the restrictions, explain why in your description. Now having said that, the restrictions require some elaboration. In general, the restrictions are meant to avoid the explicit use of these features. "No comparison operators may be used" - At some level there must be some test that allows the solution to get at the length and determine if one string is longer. Comparison operators, in particular any less/greater comparison should be avoided. Representing the length of any string as a number should also be avoided. Various approaches allow for detecting the end of a string. Some of these involve implicitly using equal/not-equal; however, explicitly using equal/not-equal should be acceptable. "No arithmetic operations" - Again, at some level something may have to advance through the string. Often there are ways a language can do this implicitly advance a cursor or pointer without explicitly using a +, - , ++, --, add, subtract, etc. The datatype restrictions are amongst the most difficult to reinterpret. In the language of the original challenge strings are atomic datatypes and structured datatypes like lists are quite distinct and have many different operations that apply to them. This becomes a bit fuzzier with languages with a different programming paradigm. The intent would be to avoid using an easy structure to accumulate the longest strings and spit them out. There will be some natural reinterpretation here. To make this a bit more concrete, here are a couple of specific examples: In C, a string is an array of chars, so using a couple of arrays as strings is in the spirit while using a second array in a non-string like fashion would violate the intent. In APL or J, arrays are the core of the language so ruling them out is unfair. Meeting the spirit will come down to how they are used. Please keep in mind these are just examples and you may hit new territory finding a solution. There will be other cases like these. Explain your reasoning. You may want to open a discussion on the talk page as well. The added "No rereading" restriction is for practical reasons, re-reading stdin should be broken. I haven't outright banned the use of other files but I've discouraged them as it is basically another form of a list. Somewhere there may be a language that just sings when doing file manipulation and where that makes sense; however, for most there should be a way to accomplish without resorting to an externality. At the end of the day for the implementer this should be a bit of fun. As an implementer you represent the expertise in your language, the reader may have no knowledge of your language. For the reader it should give them insight into how people think outside the box in other languages. Comments, especially for non-obvious (to the reader) bits will be extremely helpful. While the implementations may be a bit artificial in the context of this task, the general techniques may be useful elsewhere.
#PHP
PHP
<?php   echo 'Enter strings (empty string to finish) :', PHP_EOL;   $output = $previous = readline(); while ($current = readline()) { $p = $previous; $c = $current; // Remove first character from strings until one of them is empty while ($p and $c) { $p = substr($p, 1); $c = substr($c, 1); } // If $p and $c are empty : strings are of equal length if (!$p and !$c) { $output .= PHP_EOL . $current; } // If $c is not empty, $current is longer if ($c) { $output = $previous = $current; } }   echo 'Longest string(s) = ', PHP_EOL, $output, PHP_EOL;