task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Vala | Vala |
void main(){
string sentence = "This is a sample sentence.";
Regex a = new Regex("s[ai]mple"); // if using \n type expressions, use triple " for string literals as easy method to escape them
if (a.match(sentence)){
stdout.printf("\"%s\" is in \"%s\"!\n", a.get_pattern(), sentence);
}
string sentence_replacement = "cat";
sentence = a.replace(sentence, sentence.length, 0, sentence_replacement);
stdout.printf("Replaced sentence is: %s\n", sentence);
}
|
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Elm | Elm | -- The import on the next line provides the reverse string
-- functionality satisfying the rosettacode.org task description.
import String exposing (reverse)
-- The rest is fairly boilerplate code demonstrating
-- interactively that the reverse function works.
import Html exposing (Html, Attribute, text, div, input)
import Html.Attributes exposing (placeholder, value, style)
import Html.Events exposing (on, targetValue)
import Html.App exposing (beginnerProgram)
main = beginnerProgram { model = "", view = view, update = update }
update newStr oldStr = newStr
view : String -> Html String
view forward =
div []
([ input
[ placeholder "Enter a string to be reversed."
, value forward
, on "input" targetValue
, myStyle
]
[]
] ++
[ let backward = reverse forward
in div [ myStyle] [text backward]
])
myStyle : Attribute msg
myStyle =
style
[ ("width", "100%")
, ("height", "20px")
, ("padding", "5px 0 0 5px")
, ("font-size", "1em")
, ("text-align", "left")
] |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #TXR | TXR | txr reverse.txr verse.txt |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #XPL0 | XPL0 | code ChIn=7, ChOut=8;
int C, CC;
repeat C:= ChIn(1); CC:= C&~$20; \CC handles lowercase too
ChOut(0, C + (if CC>=^A & CC<=^M then +13
else if CC>=^N & CC<=^Z then -13
else 0));
until C = $1A; \EOF |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #XBasic | XBasic |
PROGRAM "romanenc"
VERSION "0.0000"
DECLARE FUNCTION Entry()
INTERNAL FUNCTION ToRoman$(aValue%%)
' 3888 or MMMDCCCLXXXVIII (15 chars) is the longest string properly encoded with these symbols.
FUNCTION Entry()
PRINT ToRoman$(1990) ' MCMXC
PRINT ToRoman$(2018) ' MMXVIII
PRINT ToRoman$(3888) ' MMMDCCCLXXXVIII
END FUNCTION
FUNCTION ToRoman$(aValue%%)
DIM weights%%[12]
DIM symbols$[12]
weights%%[0] = 1000
weights%%[1] = 900
weights%%[2] = 500
weights%%[3] = 400
weights%%[4] = 100
weights%%[5] = 90
weights%%[6] = 50
weights%%[7] = 40
weights%%[8] = 10
weights%%[9] = 9
weights%%[10] = 5
weights%%[11] = 4
weights%%[12] = 1
symbols$[0] = "M"
symbols$[1] = "CM"
symbols$[2] = "D"
symbols$[3] = "CD"
symbols$[4] = "C"
symbols$[5] = "XC"
symbols$[6] = "L"
symbols$[7] = "XL"
symbols$[8] = "X"
symbols$[9] = "IX"
symbols$[10] = "V"
symbols$[11] = "IV"
symbols$[12] = "I"
destination$ = ""
i@@ = 0
DO WHILE (i@@ <= 12) AND (aValue%% > 0)
DO WHILE aValue%% >= weights%%[i@@]
destination$ = destination$ + symbols$[i@@]
aValue%% = aValue%% - weights%%[i@@]
LOOP
i@@ = i@@ + 1
LOOP
RETURN destination$
END FUNCTION
END PROGRAM
|
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Mercury | Mercury | :- module repeat.
:- interface.
:- import_module string, char, int.
:- func repeat_char(char, int) = string.
:- func repeat(string, int) = string.
:- implementation.
:- import_module stream, stream.string_writer, string.builder.
repeat_char(C, N) = string.duplicate_char(C, N).
repeat(String, Count) = Repeated :-
S0 = string.builder.init,
Repeated = string.builder.to_string(S),
printn(string.builder.handle, Count, String, S0, S).
:- pred printn(Stream, int, string, State, State)
<= (stream.writer(Stream, string, State),
stream.writer(Stream, character, State)).
:- mode printn(in, in, in, di, uo) is det.
printn(Stream, N, String, !S) :-
( N > 0 ->
print(Stream, String, !S),
printn(Stream, N - 1, String, !S)
; true ). |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #min | min | "ha" 5 repeat print |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Julia | Julia | a = [1, 2, 3, 4, 1, 2, 3, 4]
@show unique(a) Set(a) |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Racket | Racket |
#lang racket
(require math)
(define (reduced-echelon M)
(matrix-row-echelon M #t #t))
(reduced-echelon
(matrix [[1 2 -1 -4]
[2 3 -1 -11]
[-2 0 -3 22]]))
|
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #.D0.9C.D0.9A-61.2F52 | МК-61/52 | 1 e^x С/П
пи С/П
КвКор С/П
lg С/П
e^x С/П
|x| С/П
П0 ^ [x] П1 - x=0 09 ИП0 С/П ЗН
x>=0 14 ИП1 С/П ИП1 1 - С/П
П0 ^ [x] П1 - x=0 09 ИП0 С/П ЗН
x<0 14 ИП1 С/П ИП1 1 + С/П
x^y С/П |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Modula-3 | Modula-3 | Math.E;
Math.Pi;
Math.sqrt(x);
Math.log(x);
Math.exp(x);
ABS(x); (* Built in function. *)
FLOOR(x); (* Built in function. *)
CEILING(x); (* Built in function. *)
Math.pow(x, y); |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #PARI.2FGP | PARI/GP | str = concat(apply(s->concat(s,"\n"), readstr("file.txt"))) |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Pascal | Pascal | perl -n -0777 -e 'print "file len: ".length' stuff.txt |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #VBScript | VBScript | text = "I need more coffee!!!"
Set regex = New RegExp
regex.Global = True
regex.Pattern = "\s"
If regex.Test(text) Then
WScript.StdOut.Write regex.Replace(text,vbCrLf)
Else
WScript.StdOut.Write "No matching pattern"
End If |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Vedit_macro_language | Vedit macro language | if (Match(".* string$", REGEXP)==0) {
Statline_Message("This line ends with 'string'")
} |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Emacs_Lisp | Emacs Lisp | (reverse "Hello World") |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #UNIX_Shell | UNIX Shell | while read -a words; do
for ((i=${#words[@]}-1; i>=0; i--)); do
printf "%s " "${words[i]}"
done
echo
done << END
---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------
END |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #VBA | VBA |
Option Explicit
Sub Main()
Dim Lines(9) As String, i&
'Input
Lines(0) = "------------- Ice And Fire -------------"
Lines(1) = ""
Lines(2) = "fire, in end will world the say Some"
Lines(3) = "ice. in say Some"
Lines(4) = "desire of tasted I've what From"
Lines(5) = "fire. favor who those with hold I"
Lines(6) = ""
Lines(7) = "... elided paragraph last ..."
Lines(8) = ""
Lines(9) = "Frost Robert -----------------------"
'Output
For i = 0 To 9
Debug.Print ReverseLine(Lines(i), " ")
Next
End Sub
Private Function ReverseLine(Line As String, Optional Separat As String) As String
Dim T, R, i&, j&, deb&, fin&
If Len(Line) = 0 Then
ReverseLine = vbNullString
Else
If Separat = "" Then Separat = " "
T = Split(Line, Separat)
ReDim R(UBound(T)): j = LBound(T)
deb = UBound(T): fin = deb / 2
For i = deb To fin Step -1
R(j) = T(i)
R(i) = T(j)
j = j + 1
Next i
ReverseLine = Join(R, Separat)
End If
End Function |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #XSLT | XSLT | <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" />
<xsl:variable name="alpha">ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz</xsl:variable>
<xsl:variable name="rot13">NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm</xsl:variable>
<xsl:template match="body">
<xsl:apply-templates/>
</xsl:template>
<xsl:template match="rot13">
<xsl:value-of select="translate(.,$alpha,$rot13)"/>
</xsl:template>
</xsl:stylesheet> |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #XLISP | XLISP | (defun roman (n)
(define roman-numerals '((1000 "m") (900 "cm") (500 "d") (400 "cd") (100 "c") (90 "xc") (50 "l") (40 "xl") (10 "x") (9 "ix") (5 "v") (4 "iv") (1 "i")))
(defun romanize (arabic-numeral numerals roman-numeral)
(if (= arabic-numeral 0)
roman-numeral
(if (>= arabic-numeral (caar numerals))
(romanize (- arabic-numeral (caar numerals)) numerals (string-append roman-numeral (cadar numerals)))
(romanize arabic-numeral (cdr numerals) roman-numeral))))
(romanize n roman-numerals ""))
; test the function:
(display (mapcar roman '(10 2016 800 2769 1666 476 1453))) |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #MiniScript | MiniScript | str = "Lol"
print str * 5 |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Mirah | Mirah | x = StringBuilder.new
5.times do
x.append "ha"
end
puts x # ==> "hahahahaha" |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #K | K | a:4 5#20?13 / create a random 4 x 5 matrix
(12 7 12 4 3
6 3 7 4 7
3 8 3 1 2
2 12 6 4 1)
,/a / flatten to array
12 7 12 4 3 6 3 7 4 7 3 8 3 1 2 2 12 6 4 1
?,/a / distinct elements
12 7 4 3 6 8 1 2
?"chthonic eleemosynary paronomasiac"
"chtoni elmsyarp"
?("this";"that";"was";"that";"was";"this")
("this"
"that"
"was")
0 1 1 2 0 *\: 0 1 2
(0 0 0
0 1 2
0 1 2
0 2 4
0 0 0)
?0 1 1 2 0 *\: 0 1 2
(0 0 0
0 1 2
0 2 4) |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Klingphix | Klingphix | ( )
( "Now" "is" "the" "time" "for" "all" "good" "men" "to" "come" "to" "the" "aid" "of" "the" "party." )
len [
get rot over find
not (
[swap 0 put]
[nip]
) if
swap
] for
swap print drop nl
"End " input |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Raku | Raku | sub rref (@m) {
my ($lead, $rows, $cols) = 0, @m, @m[0];
for ^$rows -> $r {
return @m unless $lead < $cols;
my $i = $r;
until @m[$i;$lead] {
next unless ++$i == $rows;
$i = $r;
return @m if ++$lead == $cols;
}
@m[$i, $r] = @m[$r, $i] if $r != $i;
@m[$r] »/=» $ = @m[$r;$lead];
for ^$rows -> $n {
next if $n == $r;
@m[$n] »-=» @m[$r] »×» (@m[$n;$lead] // 0);
}
++$lead;
}
@m
}
sub rat-or-int ($num) {
return $num unless $num ~~ Rat;
return $num.narrow if $num.narrow ~~ Int;
$num.nude.join: '/';
}
sub say_it ($message, @array) {
say "\n$message";
$_».&rat-or-int.fmt(" %5s").say for @array;
}
my @M = (
[ # base test case
[ 1, 2, -1, -4 ],
[ 2, 3, -1, -11 ],
[ -2, 0, -3, 22 ],
],
[ # mix of number styles
[ 3, 0, -3, 1 ],
[ .5, 3/2, -3, -2 ],
[ .2, 4/5, -1.6, .3 ],
],
[ # degenerate case
[ 1, 2, 3, 4, 3, 1],
[ 2, 4, 6, 2, 6, 2],
[ 3, 6, 18, 9, 9, -6],
[ 4, 8, 12, 10, 12, 4],
[ 5, 10, 24, 11, 15, -4],
],
[ # larger matrix
[1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0],
[1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0],
[1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0, 0],
[0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0],
[0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, -1, 0, 0, 0, 0, 0, 0],
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0],
[0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0],
[0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0],
[0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0],
[0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, -1, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, -1, 0],
[0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0],
[0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1],
[0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0],
]
);
for @M -> @matrix {
say_it( 'Original Matrix', @matrix );
say_it( 'Reduced Row Echelon Form Matrix', rref(@matrix) );
say "\n";
} |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Neko | Neko | /**
Real constants and functions, in Neko
Tectonics:
nekoc real-constants.neko
neko real-constants
*/
var euler = $loader.loadprim("std@math_exp", 1)(1)
var pi = $loader.loadprim("std@math_pi", 0)()
var math_sqrt = $loader.loadprim("std@math_sqrt", 1)
var math_log = $loader.loadprim("std@math_log", 1)
var math_exp = $loader.loadprim("std@math_exp", 1)
var math_abs = $loader.loadprim("std@math_abs", 1)
var math_floor = $loader.loadprim("std@math_floor", 1)
var math_ceil = $loader.loadprim("std@math_ceil", 1)
var math_pow = $loader.loadprim("std@math_pow", 2)
$print("Euler : ", euler, "\n")
$print("Pi : ", pi, "\n")
$print("Sqrt(2) : ", math_sqrt(2), "\n")
$print("Log(10) : ", math_log(10), "\n")
$print("Exp(1) : ", math_pow(euler, 1), "\n")
$print("Abs(-2.2) : ", math_abs(-2.2), "\n")
$print("Floor(-2.2): ", math_floor(-2.2), "\n")
$print("Ceil(-2.2) : ", math_ceil(-2.2), "\n")
$print("Pow(2, 8) : ", math_pow(2, 8), "\n") |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Perl | Perl | perl -n -0777 -e 'print "file len: ".length' stuff.txt |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Phix | Phix | ?get_text(command_line()[2])
|
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Web_68 | Web 68 | @1Introduction.
Web 68 has access to a regular expression module
which can compile regular expressions,
use them for matching strings,
and replace strings with the matched string.
@a@<Compiler prelude@>
BEGIN
@<Declarations@>
@<Logic at the top level@>
END
@<Compiler postlude@>
@ The local compiler requires a special prelude.
@<Compiler prel...@>=
PROGRAM rosettacode regex CONTEXT VOID
USE regex,standard
@ And a special postlude.
@<Compiler post...@>=
FINISH
@1Regular expressions.
Compile a regular expression and match a string using it.
@<Decl...@>=
STRING regexp="string$";
REF REGEX rx=rx compile(regexp);
@ Declare a string for the regular expression to match.
@<Decl...@>=
STRING to match = "This is a string";
@ Define a routine to print the result of matching.
@<Decl...@>=
OP MATCH = (REF REGEX rx,STRING match)STRING:
IF rx match(rx,match,LOC SUBEXP)
THEN "matches"
ELSE "doesn't match"
FI;
@ Check whether the regular expression matches the string.
@<Logic...@>=
print(("String """,regexp,""" ",rx MATCH to match,
" string """,to match,"""",newline))
@ The end.
This program is processed by tang to produce Algol 68 code which has to be compiled by the a68toc compiler.
It's output is then compiled by gcc to produce a binary program. The script 'ca' provided with the Debian
package algol68toc requires the following command to process this program.
ca -l mod rosettacoderegex.w68
That's it. The resulting binary will print
'String "string$" matches string "This is a string"' |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Wren | Wren | import "/pattern" for Pattern
var s = "This is a story about R2D2 and C3P0 who are best friends."
var p = Pattern.new("/u/d/u/d")
var matches = p.findAll(s)
System.print("Original string:\n%(" %(s)")")
System.print("\nThe following matches were found:")
matches.each{ |m| System.print(" %(m.text) at index %(m.index)") }
System.print("\nAfter replacing the second match:")
System.print(" %(p.replace(s, "Luke", 2, 1))") // replace 2nd match with "Luke"
System.print("\nReformatted phone list example:")
var phoneList = [
"Harry Potter 98951212",
"Hermione Granger 59867125",
"Ron Weasley 56471832"
]
var p2 = Pattern.new("[+1/a] [+1/a] [=8/d]")
for (record in phoneList) {
var m = p2.find(record)
var t = m.capsText
System.print(" %(t[1]), %(t[0]) - %(t[2])")
} |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Erlang | Erlang | 1> lists:reverse("reverse!").
"!esrever" |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #VBScript | VBScript |
Option Explicit
Dim objFSO, objInFile, objOutFile
Dim srcDir, line
Set objFSO = CreateObject("Scripting.FileSystemObject")
srcDir = objFSO.GetParentFolderName(WScript.ScriptFullName) & "\"
Set objInFile = objFSO.OpenTextFile(srcDir & "In.txt",1,False,0)
Set objOutFile = objFSO.OpenTextFile(srcDir & "Out.txt",2,True,0)
Do Until objInFile.AtEndOfStream
line = objInFile.ReadLine
If line = "" Then
objOutFile.WriteLine ""
Else
objOutFile.WriteLine Reverse_String(line)
End If
Loop
Function Reverse_String(s)
Dim arr, i
arr = Split(s," ")
For i = UBound(arr) To LBound(arr) Step -1
If arr(i) <> "" Then
If i = UBound(arr) Then
Reverse_String = Reverse_String & arr(i)
Else
Reverse_String = Reverse_String & " " & arr(i)
End If
End If
Next
End Function
objInFile.Close
objOutFile.Close
Set objFSO = Nothing
|
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #Yabasic | Yabasic |
s$ = "nowhere ABJURER"
print " Cadena original : ", s$
print " Tras codificar : ", Rot13$(s$)
print "Tras decodificar : ", Rot13$(Rot13$(s$))
end
sub Rot13$ (s$)
local cad$
cad$ = ""
for i = 1 to len(s$)
temp = asc(mid$(s$, i, 1))
if temp >= 65 and temp <= 90 then // A to Z
temp = (mod((temp - 52), 26)) + 65
elsif temp >= 97 And temp <= 122 then // a to z
temp = (mod((temp - 84), 26)) + 97
end if
cad$ = cad$ + chr$(temp)
next i
return cad$
end sub
|
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #XPL0 | XPL0 | proc Rom(N, A, B, C); \Display 1..9 in Roman numerals
int N, A, B, C, I;
[case N of
9: [ChOut(0, C); ChOut(0, A)]; \XI
8,7,6,5:[ChOut(0, B); for I:= 1 to rem(N/5) do ChOut(0, C)]; \V
4: [ChOut(0, C); ChOut(0, B)] \IV
other for I:= 1 to N do ChOut(0, C); \I
];
proc Roman(N); \Display N in Roman numerals
int N, Q;
[Q:= N/1000; N:= rem(0); \0..3999
Rom(Q, ^?, ^?, ^M);
Q:= N/100; N:= rem(0); \0..999
Rom(Q, ^M, ^D, ^C);
Q:= N/10; N:= rem(0); \0..99
Rom(Q, ^C, ^L, ^X);
Rom(N, ^X, ^V, ^I); \0..9
];
int Tbl, I;
[Tbl:= [1990, 2008, 1666, 0, 1, 3999, 2020, 1234];
for I:= 0 to 7 do
[IntOut(0, Tbl(I)); Text(0, ". "); Roman(Tbl(I)); CrLf(0)];
] |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Monte | Monte |
var s := "ha " * 5
traceln(s)
|
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #MontiLang | MontiLang | |ha| 5 * PRINT . |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Kotlin | Kotlin | fun main(args: Array<String>) {
val data = listOf(1, 2, 3, "a", "b", "c", 2, 3, 4, "b", "c", "d")
val set = data.distinct()
println(data)
println(set)
} |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #REXX | REXX | /*REXX pgm performs Reduced Row Echelon Form (RREF), AKA row canonical form on a matrix)*/
cols= 0; w= 0; @. =0 /*max cols in a row; max width; matrix.*/
mat.=; mat.1= ' 1 2 -1 -4 '
mat.2= ' 2 3 -1 -11 '
mat.3= ' -2 0 -3 22 '
do r=1 until mat.r==''; _=mat.r /*build @.row.col from (matrix) mat.X*/
do c=1 until _=''; parse var _ @.r.c _
w= max(w, length(@.r.c) + 1) /*find the maximum width of an element.*/
end /*c*/
cols= max(cols, c) /*save the maximum number of columns. */
end /*r*/
rows= r-1 /*adjust the row count (from DO loop). */
call showMat 'original matrix' /*display the original matrix──►screen.*/
!= 1 /*set the working column pointer to 1.*/
/* ┌──────────────────────◄────────────────◄──── Reduced Row Echelon Form on matrix.*/
do r=1 for rows while cols>! /*begin to perform the heavy lifting. */
j= r /*use a subsitute index for the DO loop*/
do while @.j.!==0; j= j + 1
if j==rows then do; j= r; != ! + 1; if cols==! then leave r; end
end /*while*/
/* [↓] swap rows J,R (but not if same)*/
do _=1 for cols while j\==r; parse value @.r._ @.j._ with @.j._ @._._
end /*_*/
?= @.r.!
do d=1 for cols while ?\=1; @.r.d= @.r.d / ?
end /*d*/ /* [↑] divide row J by @.r.p ──unless≡1*/
do k=1 for rows; ?= @.k.! /*subtract (row K) @.r.s from row K.*/
if k==r | ?=0 then iterate /*skip if row K is the same as row R.*/
do s=1 for cols; @.k.s= @.k.s - ? * @.r.s
end /*s*/
end /*k*/ /* [↑] for the rest of numbers in row.*/
!= !+1 /*bump the working column pointer. */
end /*r*/
call showMat 'matrix RREF' /*display the reduced row echelon form.*/
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
showMat: parse arg title; say; say center(title, 3 + (cols+1) * w, '─'); say
do r=1 for rows; _=
do c=1 for cols
if @.r.c=='' then do; say "***error*** matrix element isn't defined:"
say 'row' r", column" c'.'; exit 13
end
_= _ right(@.r.c, w)
end /*c*/
say _ /*display a matrix row to the terminal.*/
end /*r*/; return |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary utf8
numeric digits 30
x = 2.5
y = 3
pad = 40
say
say 'Java Math constants & functions:'
say Rexx(' Euler''s number (e):').left(pad) Math.E
say Rexx(' Pi:').left(pad) Math.PI
say Rexx(' Square root of' x':').left(pad) Math.sqrt(x)
say Rexx(' Log(e) of' x':').left(pad) Math.log(x)
say Rexx(' Log(e) of e:').left(pad) Math.log(Math.E)
say Rexx(' Log(10) of' x':').left(pad) Math.log10(x)
say Rexx(' Log(10) of 10:').left(pad) Math.log10(10)
say Rexx(' Exponential (e**x) of' x':').left(pad) Math.exp(x)
say Rexx(' Exponential (e**x) of log(e)' x':').left(pad) Math.exp(Math.log(x))
say Rexx(' Abs of' x':').left(pad) Math.abs(x.todouble)
say Rexx(' Abs of' (-x)':').left(pad) Math.abs((-x).todouble)
say Rexx(' Floor of' x':').left(pad) Math.floor(x)
say Rexx(' Floor of' (-x)':').left(pad) Math.floor((-x))
say Rexx(' Ceiling of' x':').left(pad) Math.ceil(x)
say Rexx(' Ceiling of' (-x)':').left(pad) Math.ceil((-x))
say Rexx(' ' x 'to the power of' y':').left(pad) Math.pow(x, y)
say Rexx(' ' x 'to the power of' 1 / y':').left(pad) Math.pow(x, 1 / y)
say Rexx(' 10 to the power of log10' x':').left(pad) Math.pow(10, Math.log10(x))
-- Extras
say Rexx(' Cube root of' x':').left(pad) Math.cbrt(x)
say Rexx(' Hypotenuse of' 3 'x' 4 'right triangle:').left(pad) Math.hypot(3, 4)
say Rexx(' Max of' (-x) '&' x':').left(pad) Math.max((-x).todouble, x)
say Rexx(' Min of' (-x) '&' x':').left(pad) Math.min((-x).todouble, x)
say Rexx(' Signum of' x':').left(pad) Math.signum((x).todouble)
say Rexx(' Signum of' x '-' x':').left(pad) Math.signum((x - x).todouble)
say Rexx(' Signum of' (-x)':').left(pad) Math.signum((-x).todouble)
say
say 'NetRexx built-in support for numeric data:'
say Rexx(' Abs of' x':').left(pad) x.abs()
say Rexx(' Abs of' (-x)':').left(pad) (-x).abs()
say Rexx(' Sign of' x':').left(pad) x.sign()
say Rexx(' Sign of' x '-' x':').left(pad) (x - x).sign()
say Rexx(' Sign of' (-x)':').left(pad) (-x).sign()
say Rexx(' Max of' (-x) '&' x':').left(pad) (-x).max(x)
say Rexx(' Min of' (-x) '&' x':').left(pad) (-x).min(x)
say Rexx(' Truncate' x 'by' y':').left(pad) x.trunc(y)
say Rexx(' Format (with rounding)' x 'by' y':').left(pad) x.format(y, 0)
|
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #PHP | PHP | file_get_contents($filename) |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Picat | Picat |
main(Args) =>
File = Args[1],
String = read_file_chars(File).
|
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #zkl | zkl | var re=RegExp(".*string$");
re.matches("I am a string") //-->True
var s="I am a string thing"
re=RegExp("(string)") // () means group, ie if you see it, save it
re.search(s,True) //-->True, .search(x,True) means search for a match, ie don't need .*
p,n:=re.matched[0] //.matched-->L(L(7,6),"string")
String(s[0,p],"FOO",s[p+n,*]) //-->"I am a FOO thing"
re.search(s,True); // using .matched clears it
m:=re.matched[1];
s.replace(m,"FOO"); // -->"I am a FOO thing" |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #ERRE | ERRE |
PROGRAM REVERSE_STRING
PROCEDURE REVERSE(A$->R$)
LOCAL I%
R$=""
FOR I=1 TO LEN(A$) DO
R$=MID$(A$,I,1)+R$
END FOR
END PROCEDURE
BEGIN
A$="THE FIVE BOXING WIZARDS JUMP QUICKLY"
REVERSE(A$->R$)
PRINT(R$)
END PROGRAM
|
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #Vlang | Vlang | fn main() {
mut n := [
"---------- Ice and Fire ------------",
" ",
"fire, in end will world the say Some",
"ice. in say Some ",
"desire of tasted I've what From ",
"fire. favor who those with hold I ",
" ",
"... elided paragraph last ... ",
" ",
"Frost Robert -----------------------",
]
for i, s in n {
mut t := s.fields() // tokenize
// reverse
last := t.len - 1
for j, k in t[..t.len/2] {
t[j], t[last-j] = t[last-j], k
}
n[i] = t.join(" ")
}
// display result
for t in n {
println(t)
}
} |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #Wren | Wren | var lines = [
"---------- Ice and Fire ------------",
" ",
"fire, in end will world the say Some",
"ice. in say Some ",
"desire of tasted I've what From ",
"fire. favor who those with hold I ",
" ",
"... elided paragraph last ... ",
" ",
"Frost Robert -----------------------"
]
for (line in lines) {
var tokens = line.trim().split(" ")
tokens = tokens[-1..0]
System.print(tokens.join(" "))
} |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #zig | zig |
// Warning: modifies the buffer in-place (returns pointer to in)
fn rot13(in: [] u8) []u8 {
for (in) |*c| {
var d : u8 = c.*;
var x : u8 = d;
x = if (@subWithOverflow(u8, d | 32, 97, &x) ) x else x;
if (x < 26) {
x = (x + 13) % 26 + 65 + (d & 32);
c.* = x;
}
}
return in;
}
const msg: [:0] const u8 =
\\Lbh xabj vg vf tbvat gb or n onq qnl
\\ jura gur yrggref va lbhe nycunorg fbhc
\\ fcryy Q-V-F-N-F-G-R-E.
;
// need to copy the const string to a buffer
// before we can modify it in-place
//https://zig.news/kristoff/what-s-a-string-literal-in-zig-31e9
var buf: [500]u8 = undefined;
fn assignStr(out: []u8, str: [:0]const u8) void {
for (str) |c, i| {
out[i] = c;
}
out[str.len] = 0;
}
const print = @import("std").debug.print;
pub fn main() void {
assignStr(&buf, msg);
print("rot13={s}\n",.{rot13(&buf)});
}
|
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #XSLT | XSLT |
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/data/number">
<xsl:call-template name="for">
<xsl:with-param name="stop">13</xsl:with-param>
<xsl:with-param name="value"><xsl:value-of select="@value"></xsl:value-of></xsl:with-param>
</xsl:call-template>
</xsl:template>
<xsl:template name="for">
<xsl:param name="start">1</xsl:param>
<xsl:param name="stop">1</xsl:param>
<xsl:param name="step">1</xsl:param>
<xsl:param name="value">1</xsl:param>
<xsl:text/>
<xsl:choose>
<xsl:when test="($value > /data/roman
/numeral[@pos=$start]/@value or $value = /data/roman
/numeral[@pos=$start]/@value) ">
<xsl:value-of select="/data/roman
/numeral[@pos=$start]/@letter"/>
<xsl:call-template name="for">
<xsl:with-param name="stop">
<xsl:value-of select="$stop"/>
</xsl:with-param>
<xsl:with-param name="start">
<xsl:value-of select="$start"/>
</xsl:with-param>
<xsl:with-param name="value">
<xsl:value-of select="$value - /data/roman/numeral[@pos=$start]/@value"/>
</xsl:with-param>
</xsl:call-template>
</xsl:when>
<xsl:otherwise>
<xsl:if test="$start < $stop">
<xsl:call-template name="for">
<xsl:with-param name="stop">
<xsl:value-of select="$stop"/>
</xsl:with-param>
<xsl:with-param name="start">
<xsl:value-of select="$start + $step"/>
</xsl:with-param>
<xsl:with-param name="value">
<xsl:value-of select="$value"/>
</xsl:with-param>
</xsl:call-template>
</xsl:if>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:stylesheet>
|
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #MUMPS | MUMPS | RPTSTR(S,N)
;Repeat a string S for N times
NEW I
FOR I=1:1:N WRITE S
KILL I
QUIT
RPTSTR1(S,N) ;Functionally equivalent, but denser to read
F I=1:1:N W S
Q
|
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Lang5 | Lang5 | : dip swap '_ set execute _ ;
: remove-duplicates
[] swap do unique? length 0 == if break then loop drop ;
: unique?
0 extract swap "2dup in if drop else append then" dip ;
[1 2 6 3 6 4 5 6] remove-duplicates . |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Ring | Ring |
# Project : Reduced row echelon form
matrix = [[1, 2, -1, -4],
[2, 3, -1, -11],
[ -2, 0, -3, 22]]
ref(matrix)
for row = 1 to 3
for col = 1 to 4
if matrix[row][col] = -0
see "0 "
else
see "" + matrix[row][col] + " "
ok
next
see nl
next
func ref(m)
nrows = 3
ncols = 4
lead = 1
for r = 1 to nrows
if lead >= ncols
exit
ok
i = r
while m[i][lead] = 0
i = i + 1
if i = nrows
i = r
lead = lead + 1
if lead = ncols
exit 2
ok
ok
end
for j = 1 to ncols
temp = m[i][j]
m[i][j] = m[r][j]
m[r][j] = temp
next
n = m[r][lead]
if n != 0
for j = 1 to ncols
m[r][j] = m[r][j] / n
next
ok
for i = 1 to nrows
if i != r
n = m[i][lead]
for j = 1 to ncols
m[i][j] = m[i][j] - m[r][j] * n
next
ok
next
lead = lead + 1
next
|
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Nim | Nim | import math
var x, y = 12.5
echo E
echo PI
echo sqrt(x)
echo ln(x)
echo log10(x)
echo exp(x)
echo abs(x)
echo floor(x)
echo ceil(x)
echo pow(x, y) |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Objeck | Objeck | Float->Pi();
Float->E();
4.0->SquareRoot();
1.5->Log();
# exponential is not supported
3.99->Abs();
3.99->Floor();
3.99->Ceiling();
4.5->Ceiling(2.0); |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #PicoLisp | PicoLisp | (in "file" (till NIL T)) |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Pike | Pike | string content=Stdio.File("foo.txt")->read(); |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Euler_Math_Toolbox | Euler Math Toolbox |
>function strrev (s) := chartostr(fliplr(strtochar(s)))
>strrev("This is a test!")
!tset a si sihT
|
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #XBS | XBS | func revWords(x:string=""){
(x=="")&=>send x+"<br>";
set sp = x::split(" ");
send sp::reverse()::join(" ");
}
set lines:array=[
"---------- Ice and Fire ------------",
"",
"fire, in end will world the say Some",
"ice. in say Some",
"desire of tasted I've what From",
"fire. favor who those with hold I",
"",
"... elided paragraph last ...",
"",
"Frost Robert -----------------------",
];
foreach(v of lines){
log(revWords(v));
} |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #XPL0 | XPL0 | string 0;
def LF=$0A, CR=$0D;
proc Reverse(Str, Len); \Reverse order of chars in string
char Str; int Len;
int I, J, T;
[I:= 0;
J:= Len-1;
while I < J do
[T:= Str(I); Str(I):= Str(J); Str(J):= T;
I:= I+1; J:= J-1;
];
];
char Str;
int I, LineBase, WordBase;
[Str:=
"---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------";
I:= 0;
repeat LineBase:= I;
loop [WordBase:= I;
repeat I:= I+1 until Str(I) <= $20;
Reverse(@Str(WordBase), I-WordBase);
if Str(I)=CR or Str(I)=LF or Str(I)=0 then quit;
I:= I+1; \skip space
];
Reverse(@Str(LineBase), I-LineBase);
while Str(I)=CR or Str(I)=LF do I:= I+1;
until Str(I) = 0;
Text(0, Str);
CrLf(0);
] |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #zkl | zkl | #!/home/craigd/Bin/zkl
fcn rot13(text){
text.translate("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ",
"nopqrstuvwxyzabcdefghijklmNOPQRSTUVWXYZABCDEFGHIJKLM");
}
text:=(vm.arglist or File.stdin); // command line or pipe
text.pump(File.stdout,rot13); // rotate each word and print it
if(text.isType(List)) File.stdout.writeln(); // command line gets ending newline |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #Yabasic | Yabasic | roman$ = "M, CM, D, CD, C, XC, L, XL, X, IX, V, IV, I"
decml$ = "1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1"
sub toRoman$(value)
local res$, i, roman$(1), decml$(1), long
long = token(roman$, roman$(), ", ")
long = token(decml$, decml$(), ", ")
for i=1 to long
while(value >= val(decml$(i)))
res$ = res$ + roman$(i)
value = value - val(decml$(i))
wend
next i
return res$
end sub
print 400, " ", toRoman$(400)
print 1990, " ", toRoman$(1990)
print 2008, " ", toRoman$(2008)
print 2009, " ", toRoman$(2009)
print 1666, " ", toRoman$(1666)
print 3888, " ", toRoman$(3888)
//Output:
// 400 = CD
// 1990 = MCMXC
// 2008 = MMVIII
// 2009 = MMIX
// 1666 = MDCLXVI
// 3888 = MMMDCCCLXXXVIII |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Nanoquery | Nanoquery | "ha" * 5 |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Neko | Neko | /* Repeat a string, in Neko */
var srep = function(s, n) {
var str = ""
while n > 0 {
str += s
n -= 1
}
return str
}
$print(srep("ha", 5), "\n") |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Lasso | Lasso | local(
x = array(3,4,8,1,8,1,4,5,6,8,9,6),
y = array
)
with n in #x where #y !>> #n do => { #y->insert(#n) }
// result: array(3, 4, 8, 1, 5, 6, 9) |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Liberty_BASIC | Liberty BASIC |
a$ =" 1 $23.19 2 elbow 3 2 Bork 4 3 elbow 2 $23.19 "
print "Original set of elements = ["; a$; "]"
b$ =removeDuplicates$( a$)
print "With duplicates removed = ["; b$; "]"
end
function removeDuplicates$( in$)
o$ =" "
i =1
do
term$ =word$( in$, i, " ")
if instr( o$, " "; term$; " ") =0 and term$ <>" " then o$ =o$ +term$ +" "
i =i +1
loop until term$ =""
removeDuplicates$ =o$
end function
|
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Ruby | Ruby | # returns an 2-D array where each element is a Rational
def reduced_row_echelon_form(ary)
lead = 0
rows = ary.size
cols = ary[0].size
rary = convert_to(ary, :to_r) # use rational arithmetic
catch :done do
rows.times do |r|
throw :done if cols <= lead
i = r
while rary[i][lead] == 0
i += 1
if rows == i
i = r
lead += 1
throw :done if cols == lead
end
end
# swap rows i and r
rary[i], rary[r] = rary[r], rary[i]
# normalize row r
v = rary[r][lead]
rary[r].collect! {|x| x / v}
# reduce other rows
rows.times do |i|
next if i == r
v = rary[i][lead]
rary[i].each_index {|j| rary[i][j] -= v * rary[r][j]}
end
lead += 1
end
end
rary
end
# type should be one of :to_s, :to_i, :to_f, :to_r
def convert_to(ary, type)
ary.each_with_object([]) do |row, new|
new << row.collect {|elem| elem.send(type)}
end
end
class Rational
alias _to_s to_s
def to_s
denominator==1 ? numerator.to_s : _to_s
end
end
def print_matrix(m)
max = m[0].collect {-1}
m.each {|row| row.each_index {|i| max[i] = [max[i], row[i].to_s.length].max}}
m.each {|row| row.each_index {|i| print "%#{max[i]}s " % row[i]}; puts}
end
mtx = [
[ 1, 2, -1, -4],
[ 2, 3, -1,-11],
[-2, 0, -3, 22]
]
print_matrix reduced_row_echelon_form(mtx)
puts
mtx = [
[ 1, 2, 3, 7],
[-4, 7,-2, 7],
[ 3, 3, 0, 7]
]
reduced = reduced_row_echelon_form(mtx)
print_matrix reduced
print_matrix convert_to(reduced, :to_f) |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #OCaml | OCaml | Float.pi (* pi *)
sqrt x (* square root *)
log x (* natural logarithm--log base 10 also available (log10) *)
exp x (* exponential *)
abs_float x (* absolute value *)
abs x (* absolute value (for integers) *)
floor x (* floor *)
ceil x (* ceiling *)
x ** y (* power *)
-. x (* negation for floats *) |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Octave | Octave | e % e
pi % pi
sqrt(pi) % square root
log(e) % natural logarithm
exp(pi) % exponential
abs(-e) % absolute value
floor(pi) % floor
ceil(pi) % ceiling
e**pi % power |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #PL.2FI | PL/I |
get file (in) edit ((substr(s, i, 1) do i = 1 to 32767)) (a);
|
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #PowerShell | PowerShell | Get-Content foo.txt |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Prolog | Prolog |
:- initialization(main).
main :-
current_prolog_flag(argv, [File|_]),
read_file_to_string(File, String, []).
|
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Euphoria | Euphoria |
include std/sequence.e
printf(1, "%s\n", {reverse("abcdef") })
|
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #Yabasic | Yabasic | data " ---------- Ice and Fire ------------ "
data " "
data " fire, in end will world the say Some "
data " ice. in say Some "
data " desire of tasted I've what From "
data " fire. favor who those with hold I "
data " "
data " ... elided paragraph last ... "
data " "
data " Frost Robert ----------------------- "
data ""
dim w$(1)
do
read l$
if l$ <> "" then
n = token(l$, w$(), " ")
for i = n to 1 step -1
print w$(i), " ";
next
print
else
break
end if
loop |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
| #zkl | zkl | text:=Data(0,String,
#<<<
"---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------");
#<<<
text.pump(11,Data,fcn(s){ // process stripped lines
s.split(" ").reverse().concat(" ") + "\n" })
.text.print(); |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #Zoea | Zoea |
program: rot13
case: 1
input: abc
output: nop
case: 2
input: nop
output: abc
case: 3
input: 'ABC'
output: 'NOP'
case: 4
input: 'NOP'
output: 'ABC'
|
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #zkl | zkl | var [const] romans = L(
L("M", 1000), L("CM", 900), L("D", 500), L("CD", 400), L("C", 100),
L("XC", 90), L("L", 50), L("XL", 40), L("X", 10), L("IX", 9),
L("V", 5), L("IV", 4), L("I", 1));
fcn toRoman(i){ // convert int to a roman number
reg text = "";
foreach R,N in (romans){ text += R*(i/N); i = i%N; }
return(text);
} |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Nemerle | Nemerle | using System;
using System.Console;
module StrRep
{
Repeat(this s : string, n : int) : string
{
String('x', n).Replace("x", s)
}
Main() : void
{
WriteLine("ha".Repeat(5));
WriteLine("*".Repeat(5));
WriteLine(String('*', 5)); // repeating single char
}
} |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #NetRexx | NetRexx | /* NetRexx */
ha5 = 'ha'.copies(5)
|
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Logo | Logo | show remdup [1 2 3 a b c 2 3 4 b c d] ; [1 a 2 3 4 b c d] |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Rust | Rust |
fn main() {
let mut matrix_to_reduce: Vec<Vec<f64>> = vec![vec![1.0, 2.0 , -1.0, -4.0],
vec![2.0, 3.0, -1.0, -11.0],
vec![-2.0, 0.0, -3.0, 22.0]];
let mut r_mat_to_red = &mut matrix_to_reduce;
let rr_mat_to_red = &mut r_mat_to_red;
println!("Matrix to reduce:\n{:?}", rr_mat_to_red);
let reduced_matrix = reduced_row_echelon_form(rr_mat_to_red);
println!("Reduced matrix:\n{:?}", reduced_matrix);
}
fn reduced_row_echelon_form(matrix: &mut Vec<Vec<f64>>) -> Vec<Vec<f64>> {
let mut matrix_out: Vec<Vec<f64>> = matrix.to_vec();
let mut pivot = 0;
let row_count = matrix_out.len();
let column_count = matrix_out[0].len();
'outer: for r in 0..row_count {
if column_count <= pivot {
break;
}
let mut i = r;
while matrix_out[i][pivot] == 0.0 {
i = i+1;
if i == row_count {
i = r;
pivot = pivot + 1;
if column_count == pivot {
pivot = pivot - 1;
break 'outer;
}
}
}
for j in 0..row_count {
let temp = matrix_out[r][j];
matrix_out[r][j] = matrix_out[i][j];
matrix_out[i][j] = temp;
}
let divisor = matrix_out[r][pivot];
if divisor != 0.0 {
for j in 0..column_count {
matrix_out[r][j] = matrix_out[r][j] / divisor;
}
}
for j in 0..row_count {
if j != r {
let hold = matrix_out[j][pivot];
for k in 0..column_count {
matrix_out[j][k] = matrix_out[j][k] - ( hold * matrix_out[r][k]);
}
}
}
pivot = pivot + 1;
}
matrix_out
}
|
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Oforth | Oforth | import: math
: testReal
E println
Pi println
9 sqrt println
2 ln println
2 exp println
-3.4 abs println
3.4 exp println
2.4 floor println
3.9 floor println
5.5 floor println
-2.4 floor println
-3.9 floor println
-5.5 floor println
2.4 ceil println
3.9 ceil println
5.5 ceil println
-2.4 ceil println
-3.9 ceil println
-5.5 ceil println ; |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #ooRexx | ooRexx | /* Rexx */
-- MathLoadFuncs & MathDropFuncs are no longer needed and are effectively NOPs
-- but MathLoadFuncs does return its copyright statement when given a string argument
RxMathCopyright = MathLoadFuncs('')
say RxMathCopyright
numeric digits 16
x = 2.5
y = 3
pad = 40
digs = digits()
say
say 'Working with precision' digs
say 'Math constants & functions:'
say (' Euler''s number (e):')~left(pad) RxCalcExp(1, digs)
say (' Pi:')~left(pad) RxCalcPi(digs)
say (' Square root of' x':')~left(pad) RxCalcSqrt(x, digs)
say (' Log(e) of' x':')~left(pad) RxCalcLog(x, digs)
say (' Log(e) of e:')~left(pad) RxCalcLog(RxCalcExp(1, digs), digs)
say (' Log(10) of' x':')~left(pad) RxCalcLog10(x, digs)
say (' Log(10) of 10:')~left(pad) RxCalcLog10(10, digs)
say (' Exponential (e**x) of' x':')~left(pad) RxCalcExp(x, digs)
say (' Exponential (e**x) of log(e)' x':')~left(pad) RxCalcExp(RxCalcLog(x, digs), digs)
say (' ' x 'to the power of' y':')~left(pad) RxCalcPower(x, y, digs)
say (' ' x 'to the power of 1/'y':')~left(pad) RxCalcPower(x, 1 / y, digs)
say (' 10 to the power of log10' x':')~left(pad) RxCalcPower(10, RxCalcLog10(x), digs)
say
say 'Rexx built-in support for numeric data:'
say (' Abs of' x':')~left(pad) x~abs()
say (' Abs of' (-x)':')~left(pad) (-x)~abs()
say (' Sign of' x':')~left(pad) x~sign()
say (' Sign of' x '-' x':')~left(pad) (x - x)~sign()
say (' Sign of' (-x)':')~left(pad) (-x)~sign()
say (' Max of' (-x) '&' x':')~left(pad) (-x)~max(x)
say (' Min of' (-x) '&' x':')~left(pad) (-x)~min(x)
say (' Truncate' x 'by' y':')~left(pad) x~trunc(y)
say (' Format (with rounding)' x 'by' y':')~left(pad) x~format(y, 0)
say
say 'Use RYO functions for floor & ceiling:'
say (' Floor of' x':')~left(pad) floor(x)
say (' Floor of' (-x)':')~left(pad) floor((-x))
say (' Ceiling of' x':')~left(pad) ceiling(x)
say (' Ceiling of' (-x)':')~left(pad) ceiling((-x))
return
-- floor and ceiling functions are not part of ooRexx
floor: procedure
return arg(1)~trunc() - (arg(1) < 0) * (arg(1) \= arg(1)~trunc())
ceiling: procedure
return arg(1)~trunc() + (arg(1) > 0) * (arg(1) \= arg(1)~trunc())
::requires 'RxMath' library |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #PureBasic | PureBasic | Number.b = ReadByte(#File)
Length.i = ReadData(#File, *MemoryBuffer, LengthToRead)
Number.c = ReadCharacter(#File)
Number.d = ReadDouble(#File)
Number.f = ReadFloat(#File)
Number.i = ReadInteger(#File)
Number.l = ReadLong(#File)
Number.q = ReadQuad(#File)
Text$ = ReadString(#File [, Flags])
Number.w = ReadWord(#File) |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Python | Python | open(filename).read() |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Explore | Explore |
## இந்த நிரல் தரப்படும் சரம் ஒன்றைத் தலைகீழாகத் திருப்பி அச்சிடும்
## உதாரணமாக "abc" என்ற சரம் தரப்பட்டால் அதனைத் திருப்பி "cba" என அச்சிடும்
## "எழில்" மொழியின்மூலம் இரண்டு வகைகளில் இதனைச் செய்யலாம். இரண்டு உதாரணங்களும் இங்கே தரப்பட்டுள்ளன
நிரல்பாகம் திருப்புக (சரம்1)
## முதல் வகை
சரம்2 = ""
@( சரம்1 இல் இ) ஒவ்வொன்றாக
சரம்2 = இ + சரம்2
முடி
பின்கொடு சரம்2
முடி
நிரல்பாகம் மீண்டும்திருப்புக (சரம்1)
## இரண்டாம் வகை
சரநீளம் = len(சரம்1)
சரம்2 = ""
@(எண் = 0, எண் < சரநீளம், எண் = எண் + 1) ஆக
சரம்2 = எடு(சரம்1, எண்) + சரம்2
முடி
பின்கொடு சரம்2
முடி
அ = உள்ளீடு("ஓர் எழுத்துச் சரத்தைத் தாருங்கள் ")
பதிப்பி "நீங்கள் தந்த எழுத்துச் சரம்" அ
பதிப்பி "அதனை முதல் வகையில் திருப்பியுள்ளோம்: " திருப்புக(அ)
பதிப்பி "வேறொரு வகையில் திருப்பியுள்ளோம்: " மீண்டும்திருப்புக(அ)
|
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #Zoea_Visual | Zoea Visual | 10 CLS
20 INPUT "Enter a string: ", s$
30 LET a$ = "": REM a$ is the encoded string
40 FOR l = 1 TO LEN(s$)
50 LET i$ = s$(l): REM i$ is the letter being worked on
60 IF i$ < "A" OR i$ > "Z" THEN GO TO 100
70 LET c$ = CHR$(CODE(i$) + 13): REM c$ is the encoded letter
80 IF c$ > "Z" THEN LET c$ = CHR$(CODE(c$) - 26)
90 GO TO 300
100 IF i$ < "a" OR i$ > "z" THEN GO TO 200
110 LET c$ = CHR$(CODE(i$) + 13)
120 IF c$ > "z" THEN LET c$ = CHR$(CODE(c$) - 26)
130 GO TO 300
200 LET c$ = i$
300 LET a$ = a$ + c$
310 NEXT l
320 PRINT a$ |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #Zoea | Zoea |
program: decimal_roman
input: 12
output: 'XII'
|
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #NewLISP | NewLISP | (dup "ha" 5) |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
# Repeat a char.
echo repeat('a', 5) # -> "aaaaa".
# Repeat a string.
echo repeat("ha", 5) # -> "hahahahaha". |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Lua | Lua | items = {1,2,3,4,1,2,3,4,"bird","cat","dog","dog","bird"}
flags = {}
io.write('Unique items are:')
for i=1,#items do
if not flags[items[i]] then
io.write(' ' .. items[i])
flags[items[i]] = true
end
end
io.write('\n') |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Sage | Sage | sage: m = matrix(ZZ, [[1,2,-1,-4],[2,3,-1,-11],[-2,0,-3,22]])
sage: m.rref()
[ 1 0 0 -8]
[ 0 1 0 1]
[ 0 0 1 -2] |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Oz | Oz | {ForAll
[
{Exp 1.} %% 2.7183 Euler's number: not predefined
4. * {Atan2 1. 1.} %% 3.1416 pi: not predefined
{Sqrt 81.} %% 9.0 square root; expects a float
{Log 2.7183} %% 1.0 natural logarithm
{Abs ~1} %% 1 absolute value; expects a float or an integer
{Floor 1.999} %% 1.0 floor; expects and returns a float
{Ceil 1.999} %% 2.0 ceiling; expects and returns a float
{Pow 2 3} %% 8 power; both arguments must be of the same type
]
Show} |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #PARI.2FGP | PARI/GP | [exp(1), Pi, sqrt(2), log(2), abs(2), floor(2), ceil(2), 2^3] |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Quackery | Quackery | $ "myfile.txt" sharefile |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
| #Q | Q | q)file:read0`:file.txt
"First line of file"
"Second line of file"
"" |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
| #Ezhil | Ezhil |
## இந்த நிரல் தரப்படும் சரம் ஒன்றைத் தலைகீழாகத் திருப்பி அச்சிடும்
## உதாரணமாக "abc" என்ற சரம் தரப்பட்டால் அதனைத் திருப்பி "cba" என அச்சிடும்
## "எழில்" மொழியின்மூலம் இரண்டு வகைகளில் இதனைச் செய்யலாம். இரண்டு உதாரணங்களும் இங்கே தரப்பட்டுள்ளன
நிரல்பாகம் திருப்புக (சரம்1)
## முதல் வகை
சரம்2 = ""
@( சரம்1 இல் இ) ஒவ்வொன்றாக
சரம்2 = இ + சரம்2
முடி
பின்கொடு சரம்2
முடி
நிரல்பாகம் மீண்டும்திருப்புக (சரம்1)
## இரண்டாம் வகை
சரநீளம் = len(சரம்1)
சரம்2 = ""
@(எண் = 0, எண் < சரநீளம், எண் = எண் + 1) ஆக
சரம்2 = எடு(சரம்1, எண்) + சரம்2
முடி
பின்கொடு சரம்2
முடி
அ = உள்ளீடு("ஓர் எழுத்துச் சரத்தைத் தாருங்கள் ")
பதிப்பி "நீங்கள் தந்த எழுத்துச் சரம்" அ
பதிப்பி "அதனை முதல் வகையில் திருப்பியுள்ளோம்: " திருப்புக(அ)
பதிப்பி "வேறொரு வகையில் திருப்பியுள்ளோம்: " மீண்டும்திருப்புக(அ)
|
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
| #ZX_Spectrum_Basic | ZX Spectrum Basic | 10 CLS
20 INPUT "Enter a string: ", s$
30 LET a$ = "": REM a$ is the encoded string
40 FOR l = 1 TO LEN(s$)
50 LET i$ = s$(l): REM i$ is the letter being worked on
60 IF i$ < "A" OR i$ > "Z" THEN GO TO 100
70 LET c$ = CHR$(CODE(i$) + 13): REM c$ is the encoded letter
80 IF c$ > "Z" THEN LET c$ = CHR$(CODE(c$) - 26)
90 GO TO 300
100 IF i$ < "a" OR i$ > "z" THEN GO TO 200
110 LET c$ = CHR$(CODE(i$) + 13)
120 IF c$ > "z" THEN LET c$ = CHR$(CODE(c$) - 26)
130 GO TO 300
200 LET c$ = i$
300 LET a$ = a$ + c$
310 NEXT l
320 PRINT a$ |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
| #Zoea_Visual | Zoea Visual | function printroman () {
local -a conv
local number=$1 div rom num out
conv=(I 1 IV 4 V 5 IX 9 X 10 XL 40 L 50 XC 90 C 100 CD 400 D 500 CM 900 M 1000)
for num rom in ${(Oa)conv}; do
(( div = number / num, number = number % num ))
while (( div-- > 0 )); do
out+=$rom
done
done
echo $out
} |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
| #Objeck | Objeck | bundle Default {
class Repeat {
function : Main(args : String[]) ~ Nil {
Repeat("ha", 5)->PrintLine();
}
function : Repeat(string : String, max : Int) ~ String {
repeat : String := String->New();
for(i := 0; i < max; i += 1;) {
repeat->Append(string);
};
return repeat;
}
}
} |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
| #Maple | Maple | > L := [ 1, 2, 1, 2, 3, 3, 2, 1, "a", "b", "b", "a", "c", "b" ];
L := [1, 2, 1, 2, 3, 3, 2, 1, "a", "b", "b", "a", "c", "b"]
> [op]({op}(L));
[1, 2, 3, "a", "b", "c"] |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
| #Scheme | Scheme | (define (reduced-row-echelon-form matrix)
(define (clean-down matrix from-row column)
(cons (car matrix)
(if (zero? from-row)
(map (lambda (row)
(map -
row
(map (lambda (element)
(/ (* element (list-ref row column))
(list-ref (car matrix) column)))
(car matrix))))
(cdr matrix))
(clean-down (cdr matrix) (- from-row 1) column))))
(define (clean-up matrix until-row column)
(if (zero? until-row)
matrix
(cons (map -
(car matrix)
(map (lambda (element)
(/ (* element (list-ref (car matrix) column))
(list-ref (list-ref matrix until-row) column)))
(list-ref matrix until-row)))
(clean-up (cdr matrix) (- until-row 1) column))))
(define (normalise matrix row with-column)
(if (zero? row)
(cons (map (lambda (element)
(/ element (list-ref (car matrix) with-column)))
(car matrix))
(cdr matrix))
(cons (car matrix) (normalise (cdr matrix) (- row 1) with-column))))
(define (repeat procedure matrix indices)
(if (null? indices)
matrix
(repeat procedure
(procedure matrix (car indices) (car indices))
(cdr indices))))
(define (iota start stop)
(if (> start stop)
(list)
(cons start (iota (+ start 1) stop))))
(let ((indices (iota 0 (- (length matrix) 1))))
(repeat normalise
(repeat clean-up
(repeat clean-down
matrix
indices)
indices)
indices))) |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
| #Pascal | Pascal | { Euler’s constant }
exp(1)
{ principal square root of `x` }
sqrt(x)
{ natural logarithm }
ln(x)
{ exponential }
exp(x)
{ absolute value }
abs(x) |
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