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http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Prolog
Prolog
  wheel235(L) :- W = [6, 4, 2, 4, 2, 4, 6, 2 | W], lazy_list(accumulate, 1/W, L).   accumulate(M/[A|As], N/As, N) :- N is M + A.   roll235wheel(Limit, A) :- wheel235(W), append(A, [N|_], W), N > Limit, !.   prime235(N) :- % N is prime excepting multiples of 2, 3, 5. wheel235(W), wheel_prime...
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#JavaScript
JavaScript
var a = []; for (var i = 1; i < 23; i++) a[i] = i + Math.floor(1/2 + Math.sqrt(i)); console.log(a);   for (i = 1; i < 1000000; i++) if (Number.isInteger(i + Math.floor(1/2 + Math.sqrt(i))) === false) { console.log("The ",i,"th element of the sequence is a square"); }
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#jq
jq
def A000037: . + (0.5 + sqrt | floor);   def is_square: sqrt | . == floor;   "For n up to and including 22:", (range(1;23) | A000037), "Check for squares for n up to 1e6:", (range(1;1e6+1) | A000037 | select( is_square ))
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#Groovy
Groovy
def s1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] as Set def m1 = 6 def m2 = 7 def s2 = [0, 2, 4, 6, 8] as Set assert m1 in s1  : 'member' assert ! (m2 in s2)  : 'not a member' def su = s1 + s2 assert su == [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] as Set : 'union...
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#CLU
CLU
% Sieve of Eratosthenes eratosthenes = proc (n: int) returns (array[bool]) prime: array[bool] := array[bool]$fill(1, n, true) prime[1] := false   for p: int in int$from_to(2, n/2) do if prime[p] then for c: int in int$from_to_by(p*p, n, p) do prime[c] := false ...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioin...
#Spin
Spin
con _clkmode = xtal1+pll16x _clkfreq = 80_000_000   obj ser : "FullDuplexSerial"   pub main | i, j   ser.start(31, 30, 0, 115200)   repeat i from 0 to 15 repeat j from i + 32 to 127 step 16 if j < 100 ser.tx(32) ser.dec(j) ser.str(string(": ")) case j 32: ...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioin...
#Standard_ML
Standard ML
fun Table n 127 = " 127: 'DEL'\n" | Table 0 x = "\n" ^ (Table 10 x) | Table n x = (StringCvt.padLeft #" " 4 (Int.toString x)) ^ ": '" ^ (str (chr x)) ^ "' " ^ ( Table (n-1) (x+1)) ;   print (Table 10 32) ;
http://rosettacode.org/wiki/Sierpinski_triangle
Sierpinski triangle
Task Produce an ASCII representation of a Sierpinski triangle of order   N. Example The Sierpinski triangle of order   4   should look like this: * * * * * * * * * * * * * * * ...
#Yabasic
Yabasic
sub rep$(n, c$) local i, s$   for i = 1 to n s$ = s$ + c$ next return s$ end sub   sub sierpinski(n) local lim, y, x   lim = 2**n - 1 for y = lim to 0 step -1 print rep$(y, " "); for x = 0 to lim-y if and(x, y) then print " "; else print "* "; end if ne...
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Scala
Scala
def nextCarpet(carpet: List[String]): List[String] = ( carpet.map(x => x + x + x) ::: carpet.map(x => x + x.replace('#', ' ') + x) ::: carpet.map(x => x + x + x))   def sierpinskiCarpets(n: Int) = (Iterator.iterate(List("#"))(nextCarpet) drop n next) foreach println
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#Liberty_BASIC
Liberty BASIC
  print "Loading dictionary." open "unixdict.txt" for input as #1 while not(eof(#1)) line input #1, a$ dict$=dict$+" "+a$ wend close #1   print "Dictionary loaded." print "Seaching for semordnilaps."   semo$=" " 'string to hold words with semordnilaps   do i=i+1 w$=word$(dict$,i) p$=reverseString$(w...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#PicoLisp
PicoLisp
(de factor (N) (make (let (D 2 L (1 2 2 . (4 2 4 2 4 6 2 6 .)) M (sqrt N) ) (while (>= M D) (if (=0 (% N D)) (setq M (sqrt (setq N (/ N (link D)))) ) (inc 'D (pop 'L)) ) ) (link N) ) ) )   (println ...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#PL.2FI
PL/I
*process source attributes xref nest or(!); /*-------------------------------------------------------------------- * 22.02.2014 Walter Pachl using the is_prime code from * PL/I 'prime decomposition' * 23.02. WP start test for second prime with 2 or first prime found *----------------------...
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#Forth
Forth
create weight 1 , 3 , 1 , 7 , 3 , 9 ,   : char>num ( '0-9A-Z' -- 0..35 ) dup [char] 9 > 7 and - [char] 0 - ;   : check+ ( sedol -- sedol' ) 6 <> abort" wrong SEDOL length" 0 ( sum ) 6 0 do over I + c@ char>num weight I cells + @ * + loop 10 mod 10 swap - 10 mod [char] 0 + over 6 + c! 7 ;  ...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#PHP
PHP
<?php   function is_describing($number) { foreach (str_split((int) $number) as $place => $value) { if (substr_count($number, $place) != $value) { return false; } } return true; }   for ($i = 0; $i <= 50000000; $i += 10) { if (is_describing($i)) { echo $i . PHP_EO...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#PureBasic
PureBasic
EnableExplicit #SPC=Chr(32) #TB=~"\t" #TBLF=~"\t\n" Define.i a,b,l,n,count=0 Define *count.Integer=@count   Procedure.i AddCount(*c.Integer) ; *counter: by Ref *c\i+1 ProcedureReturn *c\i EndProcedure   Procedure.s FormatStr(tx$,l.i) Shared *count If AddCount(*count)%10=0 ProcedureReturn RSet(tx$,l,#SPC)...
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Julia
Julia
nonsquare(n::Real) = n + floor(typeof(n), 0.5 + sqrt(n)) @show nonsquare.(1:1_000_000) ∩ collect(1:1000) .^ 2
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#K
K
nonsquare:{x+_.5+%x} nonsquare[1_!23]
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#Haskell
Haskell
Prelude> import Data.Set Prelude Data.Set> empty :: Set Integer -- Empty set fromList [] Prelude Data.Set> let s1 = fromList [1,2,3,4,3] -- Convert list into set Prelude Data.Set> s1 fromList [1,2,3,4] Prelude Data.Set> let s2 = fromList [3,4,5,6] Prelude Data.Set> union s1 s2 -- Union fromList [1,2,3,4,5,6] Prelude D...
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#CMake
CMake
function(eratosthenes var limit) # Check for integer overflow. With CMake using 32-bit signed integer, # this check fails when limit > 46340. if(NOT limit EQUAL 0) # Avoid division by zero. math(EXPR i "(${limit} * ${limit}) / ${limit}") if(NOT limit EQUAL ${i}) message(FATAL_ERROR "limit is...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioin...
#Tcl
Tcl
  for {set i 0} {$i < 16} {incr i} { for {set j $i} {$j < 128} {incr j 16} { if {$j <= 31} { continue ;# don't show values 0 - 31 } elseif {$j == 32} { set x "SP" } elseif {$j == 127} { set x "DEL" } else { set x [format %c $j] } puts -nonewlin...
http://rosettacode.org/wiki/Sierpinski_triangle
Sierpinski triangle
Task Produce an ASCII representation of a Sierpinski triangle of order   N. Example The Sierpinski triangle of order   4   should look like this: * * * * * * * * * * * * * * * ...
#zkl
zkl
level,d := 3,T("*"); foreach n in (level + 1){ sp:=" "*(2).pow(n); d=d.apply('wrap(a){ String(sp,a,sp) }).extend( d.apply(fcn(a){ String(a," ",a) })); } d.concat("\n").println();
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Scheme
Scheme
(define (carpet n) (define (in-carpet? x y) (cond ((or (zero? x) (zero? y)) #t) ((and (= 1 (remainder x 3)) (= 1 (remainder y 3))) #f) (else (in-carpet? (quotient x 3) (quotient y 3)))))   (do ((i 0 (+ i 1))) ((not (< i (expt 3 n)))) (do ((j 0 (+...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#Lua
Lua
#!/usr/bin/env lua -- allow dictionary file and sample size to be specified on command line local dictfile = arg[1] or "unixdict.txt" local sample_size = arg[2] or 5;   -- read dictionary local f = assert(io.open(dictfile, "r")) local dict = {} for line in f:lines() do dict[line] = line:reverse() end f:close()   -- f...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#PowerShell
PowerShell
  function isPrime ($n) { if ($n -le 1) {$false} elseif (($n -eq 2) -or ($n -eq 3)) {$true} else{ $m = [Math]::Floor([Math]::Sqrt($n)) (@(2..$m | where {($_ -lt $n) -and ($n % $_ -eq 0) }).Count -eq 0) } } function semiprime ($n) { if($n -gt 3) { $lim = [Math]::Floor($n/2)+...
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#Fortran
Fortran
MODULE SEDOL_CHECK IMPLICIT NONE CONTAINS   FUNCTION Checkdigit(c) CHARACTER :: Checkdigit CHARACTER(6), INTENT(IN) :: c CHARACTER(36) :: alpha = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" INTEGER, DIMENSION(6) :: weights = (/ 1, 3, 1, 7, 3, 9 /), temp INTEGER :: i, n   DO i = 1, 6 temp(...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#Picat
Picat
self_desc(Num,L) => L = [ I.to_integer() : I in Num.to_string()], Len = L.len, if sum(L) != Len then fail end, foreach(J in L)  % cannot be a digit larger than the length of Num if J >= Len then fail end end, foreach(I in 0..Len-1) if sum([1 : J in L, I==J]) != L[I+1] then fail end en...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#PicoLisp
PicoLisp
(de selfDescribing (N) (fully '((D I) (= D (cnt = N (circ I)))) (setq N (mapcar format (chop N))) (range 0 (length N)) ) )
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Python
Python
  def prime(a): return not (a < 2 or any(a % x == 0 for x in xrange(2, int(a**0.5) + 1)))   def primes_below(n): return [i for i in range(n) if prime(i)]  
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Quackery
Quackery
[ [] swap times [ i^ isprime if [ i^ join ] ] ] is primes< ( n --> [ )   100 primes< echo
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Kotlin
Kotlin
// version 1.1   fun f(n: Int) = n + Math.floor(0.5 + Math.sqrt(n.toDouble())).toInt()   fun main(args: Array<String>) { println(" n f") val squares = mutableListOf<Int>() for (n in 1 until 1000000) { val v1 = f(n) val v2 = Math.sqrt(v1.toDouble()).toInt() if (v1 == v2 * v2) square...
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#Icon_and_Unicon
Icon and Unicon
  procedure display_set (s) writes ("[") every writes (!s || " ") write ("]") end   # fail unless s1 and s2 contain the same elements procedure set_equals (s1, s2) return subset(s1, s2) & subset(s2, s1) end   # fail if every element in s2 is not contained in s1 procedure subset (s1, s2) every (a := !s2) do { ...
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#COBOL
COBOL
*> Please ignore the asterisks in the first column of the next comments, *> which are kludges to get syntax highlighting to work. IDENTIFICATION DIVISION. PROGRAM-ID. Sieve-Of-Eratosthenes.   DATA DIVISION. WORKING-STORAGE SECTION.   01 Max-Number USAGE UNSIGNED-INT. 01 ...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. 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 Bioin...
#VBA
VBA
  Public Sub ascii() Dim s As String, i As Integer, j As Integer For i = 0 To 15 For j = 32 + i To 127 Step 16 Select Case j Case 32: s = "Spc" Case 127: s = "Del" Case Else: s = Chr(j) End Select Debug.Print Tab(10 * (j...
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Seed7
Seed7
$ include "seed7_05.s7i";   const func boolean: inCarpet (in var integer: x, in var integer: y) is func result var boolean: result is TRUE; begin while result and x <> 0 and y <> 0 do if x rem 3 = 1 and y rem 3 = 1 then result := FALSE; else x := x div 3; y := y div 3; ...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#M2000_Interpreter
M2000 Interpreter
  Module semordnilaps { Document d$ Load.Doc d$, "unixdict.txt" Inventory MyDict, Result Function s$(a$) { m$=a$:k=Len(a$):for i=1 to k {insert i, 1 m$=mid$(a$, k, 1):k--} : =m$ } L=Doc.Par(d$) m=Paragraph(d$, 0) If not Forward(d$,m) then exit i=1 ...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
data = Import["http://www.puzzlers.org/pub/wordlists/unixdict.txt", "List"]; result = DeleteDuplicates[ Select[data, MemberQ[data, StringReverse[#]] && # =!= StringReverse[#] &], (# ===StringReverse[#2]) &]; Print[Length[result], Take[result, 5]]
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Python
Python
from prime_decomposition import decompose   def semiprime(n): d = decompose(n) try: return next(d) * next(d) == n except StopIteration: return False
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Quackery
Quackery
[ factors size dup 3 4 clamp = ] is semiprime ( n --> b )   say "Semiprimes less than 100:" cr 100 times [ i^ semiprime if [ i^ echo sp ] ]
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#FreeBASIC
FreeBASIC
' version 05-07-2015 ' compile with: fbc -s console   Function check_sedol(input_nr As String) As Integer input_nr = Trim(input_nr) Dim As Integer i, j, x, nr_begin, sum Dim As String ch, legal = "AEIOU0123456789BCDFGHJKLMNPQRSTVWXYZ" Dim As Integer weight(0 To ...) = { 1, 3, 1, 7, 3, 9, 1}   x = Le...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#PowerShell
PowerShell
  function Test-SelfDescribing ([int]$Number) { [int[]]$digits = $Number.ToString().ToCharArray() | ForEach-Object {[Char]::GetNumericValue($_)} [int]$sum = 0   for ($i = 0; $i -lt $digits.Count; $i++) { $sum += $i * $digits[$i] }   $sum -eq $digits.Count }  
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#Prolog
Prolog
:- use_module(library(clpfd)).   self_describling :- forall(between(1, 10, I), (findall(N, self_describling(I,N), L), format('Len ~w, Numbers ~w~n', [I, L]))).   % search of the self_describling numbers of a given len self_describling(Len, N) :- length(L, Len), Len1 is Len - 1, L = [H|T],   % the first f...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Racket
Racket
#lang lazy (define nats (cons 1 (map add1 nats))) (define (sift n l) (filter (λ(x) (not (zero? (modulo x n)))) l)) (define (sieve l) (cons (first l) (sieve (sift (first l) (rest l))))) (define primes (sieve (rest nats))) (!! (take 25 primes))
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Raku
Raku
constant @primes = 2, 3, { first * %% none(@_), (@_[* - 1], * + 2 ... *) } ... *;   say @primes[^100];
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Lambdatalk
Lambdatalk
  {def nosquare {lambda {:n} {+ :n {floor {+ 0.5 {sqrt :n}}}}}} -> nosquare {def issquare {lambda {:n} {= {sqrt :n} {round {sqrt :n}}}}} -> issquare   {S.map nosquare {S.serie 1 22}} -> 2 3 5 6 7 8 10 11 12 13 14 15 17 18 19 20 21 22 23 24 26 27   {S.replace false by in {S.map issquare _ {S.map nosquare {S.ser...
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#J
J
union=: ~.@, intersection=: [ -. -. difference=: -. subset=: *./@e. equality=: -:&(/:~)
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#Comal
Comal
// Sieve of Eratosthenes input "Limit? ": limit dim sieve(1:limit) sqrlimit:=sqr(limit) sieve(1):=1 p:=2 while p<=sqrlimit do while sieve(p) and p<sqrlimit do p:=p+1 endwhile if p>sqrlimit then goto done for i:=p*p to limit step p do sieve(i):=1 endfor i p:=p+1 endwhile done: print 2, for i:=3 to limit do if...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. 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 Bioin...
#Visual_Basic_.NET
Visual Basic .NET
Imports System.Console Imports System.Linq.Enumerable   Module Program Sub Main() Dim Text = Function(index As Integer) If(index = 32, "Sp", If(index = 127, "Del", ChrW(index) & ""))   Dim start = 32 Do WriteLine(String.Concat(Range(0, 6).Select(Function(i) $"{start + 16 * i, -3}...
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Sidef
Sidef
var c = ['##'] 3.times { c = (c.map{|x| x * 3 } + c.map{|x| x + ' '*x.len + x } + c.map{|x| x * 3 }) } say c.join("\n")
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#Nanoquery
Nanoquery
import Nanoquery.IO   def reverse_str(string) ret = ""   for char in list(string).reverse() ret += char end   return ret end   lst = split(new(File).open("rosetta-code/unixdict.txt").readAll(), "\n") seen = list() count = 0 for w in lst w = lower(w) r = re...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref symbols nobinary   /* REXX *************************************************************** * 07.09.2012 Walter Pachl **********************************************************************/ fid = 'unixdict.txt' /* the test dictionary */...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Racket
Racket
#lang racket (require math)   (define (pair-factorize n) "Return all two-number factorizations of a number" (let ([up-limit (integer-sqrt n)]) (map (λ (x) (list x (/ n x))) (filter (λ (x) (<= x up-limit)) (divisors n)))))   (define (semiprime n) "Determine if a number is semiprime i.e. a product of two prim...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Raku
Raku
sub is-semiprime (Int $n --> Bool) { not $n.is-prime and .is-prime given $n div first $n %% *, flat grep &is-prime, 2 .. *; }   use Test; my @primes = flat grep &is-prime, 2 .. 100; for ^5 { nok is-semiprime([*] my @f1 = @primes.roll(1)), ~@f1; ok is-semiprime([*] my @f2 = @primes.roll(2))...
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#Gambas
Gambas
Public Sub Main() Dim byWeight As Byte[] = [1, 3, 1, 7, 3, 9, 1] Dim byCount, byCompute As Byte Dim siTotal As Short Dim sWork As New String[] Dim sToProcess As String[] = ["710889", "B0YBKJ", "406566", "B0YBLH", "228276", "B0YBKL", "557910", "B0YBKR", "585284", "B0YBKT", "B00030"]   For b...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#PureBasic
PureBasic
Procedure isSelfDescribing(x.q) ;returns 1 if number is self-describing, otherwise it returns 0 Protected digitCount, digit, i, digitSum Dim digitTally(10) Dim digitprediction(10)   If x <= 0 ProcedureReturn 0 ;number must be positive and non-zero EndIf   While x > 0 And i < 10 digit = x % 10 ...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#REXX
REXX
/*REXX program lists a sequence of primes by testing primality by trial division. */ parse arg n . /*get optional number of primes to find*/ if n=='' | n=="," then n= 26 /*Not specified? Then use the default.*/ tell= (n>0); n= abs(n) ...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Ring
Ring
  for i = 1 to 100 if isPrime(i) see "" + i + " " ok next see nl   func isPrime n if n < 2 return false ok if n < 4 return true ok if n % 2 = 0 return false ok for d = 3 to sqrt(n) step 2 if n % d = 0 return false ok next return true  
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Liberty_BASIC
Liberty BASIC
  for i = 1 to 22 print nonsqr( i); " "; next i print   found = 0 for i = 1 to 1000000 j = ( nonsqr( i))^0.5 if j = int( j) then found = 1 print "Found square: "; i exit for end if next i if found =0 then print "No squares found"   end   function nonsqr( n) nonsqr = n +int...
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Logo
Logo
repeat 22 [print sum # round sqrt #]
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#Java
Java
import java.util.Arrays; import java.util.Collections; import java.util.Set; import java.util.TreeSet;   public class Sets { public static void main(String[] args){ Set<Integer> a = new TreeSet<>(); //TreeSet sorts on natural ordering (or an optional comparator) //other options: HashSet (has...
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#Common_Lisp
Common Lisp
(defun sieve-of-eratosthenes (maximum) (loop with sieve = (make-array (1+ maximum) :element-type 'bit :initial-element 0) for candidate from 2 to maximum when (zerop (bit sieve candidate)) collect candidate and do (loop for composite...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. 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 Bioin...
#Vlang
Vlang
fn main() { for i in 0..16{ for j := 32 + i; j < 128; j += 16 { mut k := u8(j).ascii_str() match j { 32 { k = "Spc" } 127 { k = "Del" } else { } } ...
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Sinclair_ZX81_BASIC
Sinclair ZX81 BASIC
10 LET O=3 20 LET S=3**O 30 FOR I=0 TO S-1 40 FOR J=0 TO S-1 50 LET X=J 60 LET Y=I 70 GOSUB 120 80 IF C THEN PLOT J,I 90 NEXT J 100 NEXT I 110 GOTO 190 120 LET C=0 130 IF X-INT (X/3)*3=1 AND Y-INT (Y/3)*3=1 THEN RETURN 140 LET X=INT (X/3) 150 LET Y=INT (Y/3) 160 IF X>0 OR Y>0 THEN GOTO 130 170 LET C=1 180 RETU...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#NewLisp
NewLisp
  ;;; Get the words as a list, splitting at newline (setq data (parse (get-url "http://wiki.puzzlers.org/pub/wordlists/unixdict.txt") "\n")) ; ;;; destructive reverse wrapped into a function (define (get-reverse x) (reverse x)) ; ;;; stack of the results (setq res '()) ; ;;; Find the semordlinap and put them on the s...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#REXX
REXX
/* REXX --------------------------------------------------------------- * 20.02.2014 Walter Pachl relying on 'prime decomposition' * 21.02.2014 WP Clarification: I copied the algorithm created by * Gerard Schildberger under the task referred to above * 21.02.2014 WP Make sure that factr is not called illega...
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#Go
Go
  package main   import ( "fmt" "strings" "strconv" )   const input = `710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030   B B0003 B000300 A00030 E00030 I00030 O00030 U00030 β00030 β0003`   var weight = [...]int{1,3,1,7,3,9}   func csd(code string) string { switch len(code) { ...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#Python
Python
>>> def isSelfDescribing(n): s = str(n) return all(s.count(str(i)) == int(ch) for i, ch in enumerate(s))   >>> [x for x in range(4000000) if isSelfDescribing(x)] [1210, 2020, 21200, 3211000] >>> [(x, isSelfDescribing(x)) for x in (1210, 2020, 21200, 3211000, 42101000, 521001000, 6210001000)] [(1210, True), (2020, Tru...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Ruby
Ruby
require "prime"   pg = Prime::TrialDivisionGenerator.new p pg.take(10) # => [2, 3, 5, 7, 11, 13, 17, 19, 23, 29] p pg.next # => 31
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Rust
Rust
  fn is_prime(number: u32) -> bool { #[allow(clippy::cast_precision_loss)] let limit = (number as f32).sqrt() as u32 + 1;   // We test if the number is divisible by any number up to the limit  !(number < 2 || (2..limit).any(|x| number % x == 0)) }   fn main() { println!( "Primes below 100:\n{...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#S-BASIC
S-BASIC
  comment Prime number generator in S-BASIC. Only odd numbers are checked, and only the prime numbers previously found (up to the square root of the number currently under examination) are tested as divisors. Memory is conserved by saving only the first 50 primes as potential divisors, since that is suff...
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Lua
Lua
function nonSquare (n) return n + math.floor(1/2 + math.sqrt(n)) end   for n = 1, 22 do io.write(nonSquare(n) .. " ") end print() local sr for n = 1, 10^6 do sr = math.sqrt(nonSquare(n)) if sr == math.floor(sr) then print("Result for n = " .. n .. " is square!") os.exit() end end pri...
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#MAD
MAD
NORMAL MODE IS INTEGER BOOLEAN FOUND FOUND = 0B   R SEQUENCE OF NON-SQUARES FORMULA R FLOOR IS AUTOMATIC DUE TO INTEGER MATH INTERNAL FUNCTION NONSQR.(N) = N+(.5+SQRT.(N))   R PRINT VALUES FOR 1..N..22 THROUGH SHOW, FO...
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#JavaScript
JavaScript
  var set = new Set();   set.add(0); set.add(1); set.add('two'); set.add('three');   set.has(0); //=> true set.has(3); //=> false set.has('two'); // true set.has(Math.sqrt(4)); //=> false set.has('TWO'.toLowerCase()); //=> true   set.size; //=> 4   set.delete('two'); set.has('two'); //==> false set.size; //=> 3   //ite...
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#Cowgol
Cowgol
include "cowgol.coh";   # To change the maximum prime, change the size of this array # Everything else is automatically filled in at compile time var sieve: uint8[5000];   # Make sure all elements of the sieve are set to zero MemZero(&sieve as [uint8], @bytesof sieve);   # Generate the sieve var prime: @indexof sieve :...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. 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 Bioin...
#Wren
Wren
import "/fmt" for Fmt   for (i in 0...16) { var j = 32 + i while (j < 128) { var k = "%(String.fromByte(j))" if (j == 32) { k = "Spc" } else if (j == 127) { k = "Del" } System.write("%(Fmt.d(3, j)) : %(Fmt.s(-3, k)) ") j = j + 16 } ...
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Swift
Swift
import Foundation func sierpinski_carpet(n:Int) -> String { func middle(str:String) -> String { let spacer = str.stringByReplacingOccurrencesOfString("#", withString:" ", options:nil, range:nil) return str + spacer + str }   var carpet = ["#"] for i in 1...n { let a = carpet.map{...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#Nim
Nim
import strutils, sequtils, sets, algorithm   proc reversed(s: string): string = result = newString(s.len) for i, c in s: result[s.high - i] = c   let words = readFile("unixdict.txt").strip().splitLines() wordset = words.toHashSet revs = words.map(reversed) var pairs = zip(words, revs).filterIt(it[0] < it[...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#OCaml
OCaml
module StrSet = Set.Make(String)   let str_rev s = let len = String.length s in let r = Bytes.create len in for i = 0 to len - 1 do Bytes.set r i s.[len - 1 - i] done; Bytes.to_string r   let input_line_opt ic = try Some (input_line ic) with End_of_file -> close_in ic; None   let () = let ic = open_...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Ring
Ring
  prime = 1679 decomp(prime)   func decomp nr x = "" sum = 0 for i = 1 to nr if isPrime(i) and nr % i = 0 sum = sum + 1 x = x + string(i) + " * " ok if i = nr and sum = 2 x2 = substr(x,1,(len(x)-2)) see string(nr) + " = " + x2 + "is semiprime" + nl but i = nr and sum != 2 see st...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Ruby
Ruby
require 'prime' # 75.prime_division # Returns the factorization.75 divides by 3 once and by 5 twice => [[3, 1], [5, 2]]   class Integer def semi_prime? prime_division.sum(&:last) == 2 end end   p 1679.semi_prime? # true p ( 1..100 ).select( &:semi_prime? ) # [4, 6, 9, 10, 14, 15, 21, 22, 25, 26, 33, 34, 35, 38,...
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#Groovy
Groovy
def checksum(text) { assert text.size() == 6 && !text.toUpperCase().find(/[AEIOU]+/) : "Invalid SEDOL text: $text"   def sum = 0 (0..5).each { index -> sum += Character.digit(text.charAt(index), 36) * [1, 3, 1, 7, 3, 9][index] } text + (10 - (sum % 10)) % 10 } String.metaClass.sedol = { thi...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#Quackery
Quackery
[ tuck over peek 1+ unrot poke ] is item++ ( n [ --> [ )   [ [] 10 times [ 0 join ] swap [ 10 /mod rot item++ swap dup 0 = until ] drop ] is digitcount ( n --> [ )   [ 0 swap witheach + ] is sum ( [ --> n )   [ 0 swap witheach [ swap 10 *...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#Racket
Racket
#lang racket (define (get-digits number (lst null)) (if (zero? number) lst (get-digits (quotient number 10) (cons (remainder number 10) lst))))   (define (self-describing? number) (if (= number 0) #f (let ((digits (get-digits number))) (for/fold ((bool #t)) ((i (in-range (length ...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Scala
Scala
def sieve(nums: Stream[Int]): Stream[Int] = Stream.cons(nums.head, sieve((nums.tail).filter(_ % nums.head != 0))) val primes = 2 #:: sieve(Stream.from(3, 2))   println(primes take 10 toList) // //List(2, 3, 5, 7, 11, 13, 17, 19, 23, 29) println(primes takeWhile (_ < 30) toList) //List(2, 3, 5, 7, 11, ...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Sidef
Sidef
func prime_seq(amount, callback) { var (counter, number) = (0, 0); while (counter < amount) { if (is_prime(number)) { callback(number); ++counter; } ++number; } }   prime_seq(100, {|p| say p}); # prints the first 100 primes
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Maple
Maple
  with(NumberTheory):   nonSquareSequence := proc(n::integer) return n + floor(1 / 2 + sqrt(n)); end proc:   seq(nonSquareSequence(i), i = 1..22);   for number from 1 to 10^6 while not issqr(nonSquareSequence(number)) do end;   number;  
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
nonsq = (# + Floor[0.5 + Sqrt[#]]) &; nonsq@Range[22] If[! Or @@ (IntegerQ /@ Sqrt /@ nonsq@Range[10^6]), Print["No squares for n <= ", 10^6] ]
http://rosettacode.org/wiki/Set
Set
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A   set  is a collection of elements, without duplicates and without order. Task Show each of these set operations: Set creation Test m ∈ S -- "m is an...
#jq
jq
{"a":true, "b":true } == {"b":true, "a":true}. {"a":true} + {"b":true } == { "a":true, "b":true}
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#Crystal
Crystal
# compile with `--release --no-debug` for speed...   require "bit_array"   alias Prime = UInt64   class SoE include Iterator(Prime) @bits : BitArray; @bitndx : Int32 = 2   def initialize(range : Prime) if range < 2 @bits = BitArray.new 0 else @bits = BitArray.new((range + 1).to_i32) end ...
http://rosettacode.org/wiki/Show_ASCII_table
Show ASCII table
Task Show  the ASCII character set  from values   32   to   127   (decimal)   in a table format. 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 Bioin...
#XPL0
XPL0
int Hi, Lo; [SetHexDigits(2); Text(0, " "); for Hi:= 2 to 7 do [HexOut(0, Hi*16); Text(0, " ")]; CrLf(0); for Lo:= 0 to $F do [HexOut(0, Lo); Text(0, " "); for Hi:= 2 to 7 do [ChOut(0, Hi*16+Lo); Text(0, " ")]; CrLf(0); ]; ]
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Tcl
Tcl
package require Tcl 8.5   proc map {lambda list} { foreach elem $list { lappend result [apply $lambda $elem] } return $result }   proc sierpinski_carpet n { set carpet [list "#"] for {set i 1} {$i <= $n} {incr i} { set carpet [concat \ [map {x {subst {$x$x$x}}} $carpet] \...
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#Octave
Octave
a = strsplit(fileread("unixdict.txt"), "\n"); a = intersect(a, cellfun(@fliplr, a, "UniformOutput", false)); a = a(arrayfun(@(i) ismember(fliplr(a{i}), a(i+1:length(a))), 1:length(a))); length(a) arrayfun(@(i) printf("%s %s\n", a{i}, fliplr(a{i})), 1:5)
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Rust
Rust
extern crate primal;   fn isqrt(n: usize) -> usize { (n as f64).sqrt() as usize }   fn is_semiprime(mut n: usize) -> bool { let root = isqrt(n) + 1; let primes1 = primal::Sieve::new(root); let mut count = 0;   for i in primes1.primes_from(2).take_while(|&x| x < root) { while n % i == 0 { ...
http://rosettacode.org/wiki/Semiprime
Semiprime
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes   are also known as:   semi-primes   biprimes   bi-primes   2-almost   primes   or simply:   P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...
#Scala
Scala
object Semiprime extends App {   def isSP(n: Int): Boolean = { var nf: Int = 0 var l = n for (i <- 2 to l/2) { while (l % i == 0) { if (nf == 2) return false nf +=1 l /= i } } nf == 2 }   (2 to 100) filter {isSP(_) == true} foreach {i => print("%d ".format(...
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#Haskell
Haskell
import Data.Char (isAsciiUpper, isDigit, ord)   -------------------------- SEDOLS ------------------------   checkSum :: String -> String checkSum x = case traverse sedolValue x of Right xs -> (show . checkSumFromSedolValues) xs Left annotated -> annotated   checkSumFromSedolValues :: [Int] -> Int checkSumFro...
http://rosettacode.org/wiki/Self-describing_numbers
Self-describing numbers
Self-describing numbers You are encouraged to solve this task according to the task description, using any language you may know. There are several so-called "self-describing" or "self-descriptive" integers. An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ...
#Raku
Raku
my @values = <1210 2020 21200 3211000 42101000 521001000 6210001000 27 115508>;   for @values -> $test { say "$test is {sdn($test) ?? '' !! 'NOT ' }a self describing number."; }   sub sdn($n) { my $s = $n.Str; my $chars = $s.chars; my @a = +«$s.comb; my @b; for @a -> $i { return False if...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Spin
Spin
con _clkmode = xtal1+pll16x _clkfreq = 80_000_000   obj ser : "FullDuplexSerial"   pub main | d, n   ser.start(31, 30, 0, 115200)   repeat n from 2 to 100   repeat d from 2 to n-1 if n // d == 0 quit   if d == n ser.dec(n) ser.tx(32)   waitcnt(_clkfreq + cnt) ser.stop
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Swift
Swift
import Foundation   extension SequenceType { func takeWhile(include: Generator.Element -> Bool) -> AnyGenerator<Generator.Element> { var g = self.generate() return anyGenerator { g.next().flatMap{include($0) ? $0 : nil }} } }   var pastPrimes = [2]   var primes = anyGenerator { _ -> Int? in defer { ...
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division
Sequence of primes by trial division
Sequence of primes by trial division You are encouraged to solve this task according to the task description, using any language you may know. Task Generate a sequence of primes by means of trial division. Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by...
#Tailspin
Tailspin
  templates ifPrime def n: $; [2..~$n -> $n ~/ $ * $] -> \(<~[<=$n>]> $n ! \)! end ifPrime   templates primes [2..$ -> ifPrime] ! end primes   100 -> primes -> '$; ' -> !OUT::write  
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#MATLAB
MATLAB
function nonSquares(i)   for n = (1:i)   generatedNumber = n + floor(1/2 + sqrt(n));   if mod(sqrt(generatedNumber),1)==0 %Check to see if the sqrt of the generated number is an integer fprintf('\n%d generates a square number: %d\n', [n,generatedNumber]); return else ...
http://rosettacode.org/wiki/Sequence_of_non-squares
Sequence of non-squares
Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for   n   in the range   1   to   22 Show that no squares occur for   n   less than one million This is sequence   A000037   in the OEIS database.
#Maxima
Maxima
nonsquare(n) := n + quotient(isqrt(100 * n) + 5, 10); makelist(nonsquare(n), n, 1, 20); [2,3,5,6,7,8,10,11,12,13,14,15,17,18,19,20,21,22,23,24]   not_square(n) := isqrt(n)^2 # n$   m: 10^6$ u: makelist(i, i, 1, m)$ is(sublist(u, not_square) = sublist(map(nonsquare, u), lambda([x], x <= m))); true