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
response_seed
stringclasses
1 value
instruction_seed
stringlengths
27
14.4k
_source
stringclasses
1 value
http://rosettacode.org/wiki/Hostname
Hostname
Task Find the name of the host on which the routine is running.
#PHP
PHP
echo $_SERVER['HTTP_HOST'];
Give a code snippet in #PHP Task Find the name of the host on which the routine is running.
christopher/rosetta-code
http://rosettacode.org/wiki/First_power_of_2_that_has_leading_decimal_digits_of_12
First power of 2 that has leading decimal digits of 12
(This task is taken from a   Project Euler   problem.) (All numbers herein are expressed in base ten.) 27   =   128   and   7   is the first power of   2   whose leading decimal digits are   12. The next power of   2   whose leading decimal digits are   12   is   80, 280   =   1208925819614629174706176. Define ...
#Yabasic
Yabasic
FAC = 0.30102999566398119521373889472449302677   print p(12, 1) print p(12, 2) print p(123, 45) print p(123, 12345) print p(123, 678910) end   sub p(L, n) cont = 0 : j = 0 LS$ = str$(L) while cont < n j = j + 1 x = FAC * j //if x < len(LS$) continue while 'sino da error ...
Give a code snippet in #Yabasic (This task is taken from a   Project Euler   problem.) (All numbers herein are expressed in base ten.) 27   =   128   and   7   is the first power of   2   whose leading decimal digits are   12. The next power of   2   whose leading decimal digits are   12   is   80, 280   =   1208...
christopher/rosetta-code
http://rosettacode.org/wiki/Ulam_spiral_(for_primes)
Ulam spiral (for primes)
An Ulam spiral (of primes) is a method of visualizing primes when expressed in a (normally counter-clockwise) outward spiral (usually starting at 1),   constructed on a square grid, starting at the "center". An Ulam spiral is also known as a   prime spiral. The first grid (green) is shown with sequential integers,   ...
#Ruby
Ruby
require 'prime'   def cell(n, x, y, start=1) y, x = y - n/2, x - (n - 1)/2 l = 2 * [x.abs, y.abs].max d = y >= x ? l*3 + x + y : l - x - y (l - 1)**2 + d + start - 1 end   def show_spiral(n, symbol=nil, start=1) puts "\nN : #{n}" format = "%#{(start + n*n - 1).to_s.size}s " n.times do |y| n.times do |...
Give a code snippet in #Ruby An Ulam spiral (of primes) is a method of visualizing primes when expressed in a (normally counter-clockwise) outward spiral (usually starting at 1),   constructed on a square grid, starting at the "center". An Ulam spiral is also known as a   prime spiral. The first grid (green) is show...
christopher/rosetta-code
http://rosettacode.org/wiki/The_Twelve_Days_of_Christmas
The Twelve Days of Christmas
Task Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas. The lyrics can be found here. (You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.) Other tasks related to string operations: Metrics Array length Stri...
#PARI.2FGP
PARI/GP
days=["first","second","third","fourth","fifth","sixth","seventh","eighth","ninth","tenth","eleventh","twelfth"]; gifts=["And a partridge in a pear tree.", "Two turtle doves", "Three french hens", "Four calling birds", "Five golden rings", "Six geese a-laying", "Seven swans a-swimming", "Eight maids a-milking", "Nine ...
Give a code snippet in #PARI.2FGP Task Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas. The lyrics can be found here. (You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.) Other tasks related to string opera...
christopher/rosetta-code
http://rosettacode.org/wiki/Read_a_file_line_by_line
Read a file line by line
Read a file one line at a time, as opposed to reading the entire file at once. Related tasks Read a file character by character Input loop.
#Julia
Julia
open("input_file","r") do f for line in eachline(f) println("read line: ", line) end end
Give a code snippet in #Julia Read a file one line at a time, as opposed to reading the entire file at once. Related tasks Read a file character by character Input loop.
christopher/rosetta-code
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot ...
#Groovy
Groovy
def dotProduct = { x, y -> assert x && y && x.size() == y.size() [x, y].transpose().collect{ xx, yy -> xx * yy }.sum() }
Give a code snippet in #Groovy Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -...
christopher/rosetta-code
http://rosettacode.org/wiki/Color_quantization
Color quantization
full color Example: Gimp 16 color Color quantization is the process of reducing number of colors used in an image while trying to maintain the visual appearance of the original image. In general, it is a form of cluster analysis, if each RGB color value is considered as a coordinate triple in the 3D colorspace. There...
#D
D
import core.stdc.stdio, std.stdio, std.algorithm, std.typecons, std.math, std.range, std.conv, std.string, bitmap;   struct Col { float r, g, b; } alias Cluster = Tuple!(Col, float, Col, Col[]); enum Axis { R, G, B }   enum round = (in float x) pure nothrow @safe @nogc => cast(int)floor(x + 0.5);   enum roundRGB...
Give a code snippet in #D full color Example: Gimp 16 color Color quantization is the process of reducing number of colors used in an image while trying to maintain the visual appearance of the original image. In general, it is a form of cluster analysis, if each RGB color value is considered as a coordinate triple ...
christopher/rosetta-code
http://rosettacode.org/wiki/Binary_search
Binary search
A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm. As an analogy, consider the children's game "guess a number." The scorer has a secret number, and will only tell the p...
#8080_Assembly
8080 Assembly
org 100h ; Entry for test code jmp test     ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Binary search in array of unsigned 8-bit integers ;; B = value to look for ;; HL = begin of array (low) ;; DE = end of array, inclusive (high) ;; The entry point is 'binsrch' ;; On return, HL = location...
Give a code snippet in #8080_Assembly A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm. As an analogy, consider the children's game "guess a number." The scorer has a ...
christopher/rosetta-code
http://rosettacode.org/wiki/Taxicab_numbers
Taxicab numbers
A   taxicab number   (the definition that is being used here)   is a positive integer that can be expressed as the sum of two positive cubes in more than one way. The first taxicab number is   1729,   which is: 13   +   123       and also 93   +   103. Taxicab numbers are also known as:   taxi numbers   tax...
#XPL0
XPL0
int N, I, J, SI, SJ, Count, Tally; [Count:= 0; N:= 0; repeat Tally:= 0; I:= 1; repeat J:= I+1; repeat if N = I*I*I + J*J*J then [Tally:= Tally+1; if Tally >= 2 then [Count:= Count+1; ...
Give a code snippet in #XPL0 A   taxicab number   (the definition that is being used here)   is a positive integer that can be expressed as the sum of two positive cubes in more than one way. The first taxicab number is   1729,   which is: 13   +   123       and also 93   +   103. Taxicab numbers are also kno...
christopher/rosetta-code
http://rosettacode.org/wiki/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#Phix
Phix
with javascript_semantics function call_fn(integer f, n) return call_func(f,{f,n}) end function function Y(integer f) return f end function function fac(integer self, integer n) return iff(n>1?n*call_fn(self,n-1):1) end function function fib(integer self, integer n) return iff(n>1?call_fn(self,n-1...
Give a code snippet in #Phix In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a var...
christopher/rosetta-code
http://rosettacode.org/wiki/Inheritance/Single
Inheritance/Single
This task is about derived types;   for implementation inheritance, see Polymorphism. Inheritance is an operation of type algebra that creates a new type from one or several parent types. The obtained type is called derived type. It inherits some of the properties of its parent types. Usually inherited properties...
#F.23
F#
type Animal() = class // explicit syntax needed for empty class end   type Dog() = inherit Animal()   type Lab() = inherit Dog()   type Collie() = inherit Dog()   type Cat() = inherit Animal()
Give a code snippet in #F.23 This task is about derived types;   for implementation inheritance, see Polymorphism. Inheritance is an operation of type algebra that creates a new type from one or several parent types. The obtained type is called derived type. It inherits some of the properties of its parent types....
christopher/rosetta-code
http://rosettacode.org/wiki/ABC_problem
ABC problem
ABC problem You are encouraged to solve this task according to the task description, using any language you may know. You are given a collection of ABC blocks   (maybe like the ones you had when you were a kid). There are twenty blocks with two letters on each block. A complete alphabet is guaranteed amongst all sid...
#Java
Java
import java.util.Arrays; import java.util.Collections; import java.util.List;   public class ABC {   public static void main(String[] args) { List<String> blocks = Arrays.asList( "BO", "XK", "DQ", "CP", "NA", "GT", "RE", "TG", "QD", "FS", "JW", "HU", "VI", "AN...
Give a code snippet in #Java ABC problem You are encouraged to solve this task according to the task description, using any language you may know. You are given a collection of ABC blocks   (maybe like the ones you had when you were a kid). There are twenty blocks with two letters on each block. A complete alphabet...
christopher/rosetta-code
http://rosettacode.org/wiki/Compare_length_of_two_strings
Compare length of two strings
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#C
C
#include <stdio.h> #include <stdlib.h> #include <string.h>   int cmp(const int* a, const int* b) { return *b - *a; // reverse sort! }   void compareAndReportStringsLength(const char* strings[], const int n) { if (n > 0) { char* has_length = "has length"; char* predicate_max = "and is the lon...
Give a code snippet in #C Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Conc...
christopher/rosetta-code
http://rosettacode.org/wiki/Count_the_coins
Count the coins
There are four types of common coins in   US   currency:   quarters   (25 cents)   dimes   (10 cents)   nickels   (5 cents),   and   pennies   (1 cent) There are six ways to make change for 15 cents:   A dime and a nickel   A dime and 5 pennies   3 nickels   2 nickels and 5 pennies   A nickel and 10 pen...
#PARI.2FGP
PARI/GP
coins(v)=prod(i=1,#v,1/(1-'x^v[i])); ways(v,n)=polcoeff(coins(v)+O('x^(n+1)),n); ways([1,5,10,25],100) ways([1,5,10,25,50,100],100000)
Give a code snippet in #PARI.2FGP There are four types of common coins in   US   currency:   quarters   (25 cents)   dimes   (10 cents)   nickels   (5 cents),   and   pennies   (1 cent) There are six ways to make change for 15 cents:   A dime and a nickel   A dime and 5 pennies   3 nickels   2 nickels a...
christopher/rosetta-code
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#Lingo
Lingo
on swap (x, y) return "tmp="&x&RETURN&x&"="&y&RETURN&y&"=tmp" end
Give a code snippet in #Lingo Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericit...
christopher/rosetta-code
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conje...
#Phix
Phix
with javascript_semantics function hailstone(atom n) sequence s = {n} while n!=1 do if remainder(n,2)=0 then n /= 2 else n = 3*n+1 end if s &= n end while return s end function function hailstone_count(atom n) integer count = 1 while n!=1...
Give a code snippet in #Phix The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 ...
christopher/rosetta-code
http://rosettacode.org/wiki/Inheritance/Single
Inheritance/Single
This task is about derived types;   for implementation inheritance, see Polymorphism. Inheritance is an operation of type algebra that creates a new type from one or several parent types. The obtained type is called derived type. It inherits some of the properties of its parent types. Usually inherited properties...
#C.2B.2B
C++
class Animal { // ... };   class Dog: public Animal { // ... };   class Lab: public Dog { // ... };   class Collie: public Dog { // ... };   class Cat: public Animal { // ... };
Give a code snippet in #C.2B.2B This task is about derived types;   for implementation inheritance, see Polymorphism. Inheritance is an operation of type algebra that creates a new type from one or several parent types. The obtained type is called derived type. It inherits some of the properties of its parent typ...
christopher/rosetta-code
http://rosettacode.org/wiki/SHA-1
SHA-1
SHA-1 or SHA1 is a one-way hash function; it computes a 160-bit message digest. SHA-1 often appears in security protocols; for example, many HTTPS websites use RSA with SHA-1 to secure their connections. BitTorrent uses SHA-1 to verify downloads. Git and Mercurial use SHA-1 digests to identify commits. A US government...
#Pascal
Pascal
program RosettaSha1; uses sha1; var d: TSHA1Digest; begin d:=SHA1String('Rosetta Code'); WriteLn(SHA1Print(d)); end.
Give a code snippet in #Pascal SHA-1 or SHA1 is a one-way hash function; it computes a 160-bit message digest. SHA-1 often appears in security protocols; for example, many HTTPS websites use RSA with SHA-1 to secure their connections. BitTorrent uses SHA-1 to verify downloads. Git and Mercurial use SHA-1 digests to id...
christopher/rosetta-code
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#F.23
F#
let dot (ax, ay, az) (bx, by, bz) = ax * bx + ay * by + az * bz   let cross (ax, ay, az) (bx, by, bz) = (ay*bz - az*by, az*bx - ax*bz, ax*by - ay*bx)   let scalTrip a b c = dot a (cross b c)   let vecTrip a b c = cross a (cross b c)   [<EntryPoint>] let main _ = let a = (3.0, 4.0, 5.0) let b = ...
Give a code snippet in #F.23 A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of num...
christopher/rosetta-code
http://rosettacode.org/wiki/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#Oz
Oz
declare Y = fun {$ F} {fun {$ X} {X X} end fun {$ X} {F fun {$ Z} {{X X} Z} end} end} end   Fac = {Y fun {$ F} fun {$ N} if N == 0 then 1 else N*{F N-1} end end end}   Fib = {Y fun {$ F} fun {$ N} case ...
Give a code snippet in #Oz In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a varia...
christopher/rosetta-code
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#Arturo
Arturo
currentTime: now   print to :string.format: "YYYY-MM-dd" currentTime print to :string.format: "dddd, MMMM dd, YYYY" currentTime
Give a code snippet in #Arturo This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
christopher/rosetta-code
http://rosettacode.org/wiki/Dutch_national_flag_problem
Dutch national flag problem
The Dutch national flag is composed of three coloured bands in the order:   red     (top)   then white,   and   lastly blue   (at the bottom). The problem posed by Edsger Dijkstra is: Given a number of red, blue and white balls in random order, arrange them in the order of the colours in the Dutch national fla...
#FreeBASIC
FreeBASIC
  ' El problema planteado por Edsger Dijkstra es: ' "Dado un número de bolas rojas, azules y blancas en orden aleatorio, ' ordénelas en el orden de los colores de la bandera nacional holandesa."   Dim As String c = "RBW", n = "121509" Dim As Integer bolanum = 9 Dim As Integer d(bolanum), k, i, j Randomize Timer   Colo...
Give a code snippet in #FreeBASIC The Dutch national flag is composed of three coloured bands in the order:   red     (top)   then white,   and   lastly blue   (at the bottom). The problem posed by Edsger Dijkstra is: Given a number of red, blue and white balls in random order, arrange them in the order of th...
christopher/rosetta-code
http://rosettacode.org/wiki/Tic-tac-toe
Tic-tac-toe
Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™, Tic-Tac-Toe game.   Wikipedi...
#Lingo
Lingo
global $ -- object representing simple framework global gBoard -- current board image global gBoardTemplate -- empty board image global gHumanChip -- cross image global gComputerChip -- circle image global gM -- 3x3 matrix storing game state: 0=free cell, 1=human cell, -1=computer cell global gStep -- index of current ...
Give a code snippet in #Lingo Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™...
christopher/rosetta-code
http://rosettacode.org/wiki/Substring
Substring
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#OCaml
OCaml
$ ocaml # let s = "ABCDEFGH" ;; val s : string = "ABCDEFGH"   # let n, m = 2, 3 ;; val n : int = 2 val m : int = 3   # String.sub s n m ;; - : string = "CDE"   # String.sub s n (String.length s - n) ;; - : string = "CDEFGH"   # String.sub s 0 (String.length s - 1) ;; - : string = "ABCDEFG"   # String.sub s (String.inde...
Give a code snippet in #OCaml Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations ...
christopher/rosetta-code
http://rosettacode.org/wiki/Rare_numbers
Rare numbers
Definitions and restrictions Rare   numbers are positive integers   n   where:   n   is expressed in base ten   r   is the reverse of   n     (decimal digits)   n   must be non-palindromic   (n ≠ r)   (n+r)   is the   sum   (n-r)   is the   difference   and must be positive   the   sum   and the  ...
#F.23
F#
  // Find all Rare numbers with a digits. Nigel Galloway: September 18th., 2019. let rareNums a= let tN=set[1L;4L;5L;6L;9L] let izPS g=let n=(float>>sqrt>>int64)g in n*n=g let n=[for n in [0..a/2-1] do yield ((pown 10L (a-n-1))-(pown 10L n))]|>List.rev let rec fN i g e=seq{match e with 0->yield g |e->for n in ...
Give a code snippet in #F.23 Definitions and restrictions Rare   numbers are positive integers   n   where:   n   is expressed in base ten   r   is the reverse of   n     (decimal digits)   n   must be non-palindromic   (n ≠ r)   (n+r)   is the   sum   (n-r)   is the   difference   and must be pos...
christopher/rosetta-code
http://rosettacode.org/wiki/Environment_variables
Environment variables
Task Show how to get one of your process's environment variables. The available variables vary by system;   some of the common ones available on Unix include:   PATH   HOME   USER
#Batch_File
Batch File
echo %Foo%
Give a code snippet in #Batch_File Task Show how to get one of your process's environment variables. The available variables vary by system;   some of the common ones available on Unix include:   PATH   HOME   USER
christopher/rosetta-code
http://rosettacode.org/wiki/Substring
Substring
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#PowerShell
PowerShell
# test string $s = "abcdefgh" # test parameters $n, $m, $c, $s2 = 2, 3, [char]'d', $s2 = 'cd'   # starting from n characters in and of m length # n = 2, m = 3 $s.Substring($n-1, $m) # returns 'bcd'   # starting from n characters in, up to the end of the string # n = 2 $s.Substring($n-1) # ...
Give a code snippet in #PowerShell Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operat...
christopher/rosetta-code
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...
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations string 0; \use zero-terminated string convention int I; char Str; [Str:= GetHp; \starting address of block of local "heap" memory I:= 0; \ [does the exact same thing as Reserve(0)] loop [Str(I):= ChIn(1); if Str(...
Give a code snippet in #XPL0 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 increm...
christopher/rosetta-code
http://rosettacode.org/wiki/Xiaolin_Wu%27s_line_algorithm
Xiaolin Wu's line algorithm
Task Implement the   Xiaolin Wu's line algorithm   described in Wikipedia. This algorithm draws anti-aliased lines. Related task   See   Bresenham's line algorithm   for aliased lines.
#Pascal
Pascal
  program wu; uses SDL2, math;   const FPS = 1000 div 60; SCALE = 6;   var win: PSDL_Window; ren: PSDL_Renderer; mouse_x, mouse_y: longint; origin: TSDL_Point; event: TSDL_Event; line_alpha: byte = 255;   procedure SDL_RenderDrawWuLine(renderer: PSDL_Renderer; x1, y1, x2, y2: longint); var r, g, b...
Give a code snippet in #Pascal Task Implement the   Xiaolin Wu's line algorithm   described in Wikipedia. This algorithm draws anti-aliased lines. Related task   See   Bresenham's line algorithm   for aliased lines.
christopher/rosetta-code
http://rosettacode.org/wiki/Cyclotomic_polynomial
Cyclotomic polynomial
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and print the order of the first 10...
#Python
Python
from itertools import count, chain from collections import deque   def primes(_cache=[2, 3]): yield from _cache for n in count(_cache[-1]+2, 2): if isprime(n): _cache.append(n) yield n   def isprime(n): for p in primes(): if n%p == 0: return False ...
Give a code snippet in #Python The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and...
christopher/rosetta-code
http://rosettacode.org/wiki/Playfair_cipher
Playfair cipher
Playfair cipher You are encouraged to solve this task according to the task description, using any language you may know. Task Implement a Playfair cipher for encryption and decryption. The user must be able to choose   J  =  I     or   no   Q   in the alphabet. The output of the encrypted and decrypted message ...
#VBA
VBA
  Option Explicit   Private Type Adress Row As Integer Column As Integer End Type   Private myTable() As String   Sub Main() Dim keyw As String, boolQ As Boolean, text As String, test As Long Dim res As String keyw = InputBox("Enter your keyword : ", "KeyWord", "Playfair example") If keyw = "" Then GoTo Err...
Give a code snippet in #VBA Playfair cipher You are encouraged to solve this task according to the task description, using any language you may know. Task Implement a Playfair cipher for encryption and decryption. The user must be able to choose   J  =  I     or   no   Q   in the alphabet. The output of the enc...
christopher/rosetta-code
http://rosettacode.org/wiki/Count_in_factors
Count in factors
Task Write a program which counts up from   1,   displaying each number as the multiplication of its prime factors. For the purpose of this task,   1   (unity)   may be shown as itself. Example       2   is prime,   so it would be shown as itself.       6   is not prime;   it would be shown as   2 × 3 {\di...
#Common_Lisp
Common Lisp
(defparameter *primes* (make-array 10 :adjustable t :fill-pointer 0 :element-type 'integer))   (mapc #'(lambda (x) (vector-push x *primes*)) '(2 3 5 7))   (defun extend-primes (n) (let ((p (+ 2 (elt *primes* (1- (length *primes*)))))) (loop for i = p then (+ 2 i) while (<= (* i i) n) do (if (primep i t) (...
Give a code snippet in #Common_Lisp Task Write a program which counts up from   1,   displaying each number as the multiplication of its prime factors. For the purpose of this task,   1   (unity)   may be shown as itself. Example       2   is prime,   so it would be shown as itself.       6   is not prime;   it...
christopher/rosetta-code
http://rosettacode.org/wiki/Pythagorean_triples
Pythagorean triples
A Pythagorean triple is defined as three positive integers ( a , b , c ) {\displaystyle (a,b,c)} where a < b < c {\displaystyle a<b<c} , and a 2 + b 2 = c 2 . {\displaystyle a^{2}+b^{2}=c^{2}.} They are called primitive triples if a , b , c {\displaystyle a,b,c} are co-prime,...
#ANSI_Standard_BASIC
ANSI Standard BASIC
100 DECLARE EXTERNAL SUB tri 110 ! 120 PUBLIC NUMERIC U0(3,3), U1(3,3), U2(3,3), all, prim 130 DIM seed(3) 140 MAT READ U0, U1, U2 150 DATA 1, -2, 2, 2, -1, 2, 2, -2, 3 160 DATA 1, 2, 2, 2, 1, 2, 2, 2, 3 170 DATA -1, 2, 2, -2, 1, 2, -2, 2, 3 180 ! 190 MAT READ seed 200 DATA 3, 4, 5 210 FOR power = 1 TO 7 220 LET al...
Give a code snippet in #ANSI_Standard_BASIC A Pythagorean triple is defined as three positive integers ( a , b , c ) {\displaystyle (a,b,c)} where a < b < c {\displaystyle a<b<c} , and a 2 + b 2 = c 2 . {\displaystyle a^{2}+b^{2}=c^{2}.} They are called primitive triples if a , ...
christopher/rosetta-code
http://rosettacode.org/wiki/Attractive_numbers
Attractive numbers
A number is an   attractive number   if the number of its prime factors (whether distinct or not) is also prime. Example The number   20,   whose prime decomposition is   2 × 2 × 5,   is an   attractive number   because the number of its prime factors   (3)   is also prime. Task Show sequence items up to   120....
#ALGOL_68
ALGOL 68
BEGIN # find some attractive numbers - numbers whose prime factor counts are # # prime, n must be > 1 # PR read "primes.incl.a68" PR # find the attractive numbers # INT max number = 120; []BOOL sieve =...
Give a code snippet in #ALGOL_68 A number is an   attractive number   if the number of its prime factors (whether distinct or not) is also prime. Example The number   20,   whose prime decomposition is   2 × 2 × 5,   is an   attractive number   because the number of its prime factors   (3)   is also prime. Task...
christopher/rosetta-code
http://rosettacode.org/wiki/Truncate_a_file
Truncate a file
Task Truncate a file to a specific length.   This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes). Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating a temporary file of a reduced...
#Tcl
Tcl
package require Tcl 8.5   set f [open "file" r+]; # Truncation is done on channels chan truncate $f 1234; # Truncate at a particular length (in bytes) close $f
Give a code snippet in #Tcl Task Truncate a file to a specific length.   This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes). Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating ...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort
Sorting algorithms/Gnome sort
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 ...
#F.23
F#
let inline gnomeSort (a: _ []) = let rec loop i j = if i < a.Length then if a.[i-1] <= a.[i] then loop j (j+1) else let t = a.[i-1] a.[i-1] <- a.[i] a.[i] <- t if i=1 then loop j (j+1) else loop (i-1) j loop 1 2
Give a code snippet in #F.23 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 sor...
christopher/rosetta-code
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#Haskell
Haskell
  import Control.Monad import System.Random   -- Repeat the action until the predicate is true. until_ act pred = act >>= pred >>= flip unless (until_ act pred)   answerIs ans guess | ans == guess = putStrLn "You got it!" >> return True | otherwise = putStrLn "Nope. Guess again." >> return False   ask = liftM ...
Give a code snippet in #Haskell Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a...
christopher/rosetta-code
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...
Give a code snippet in #Racket 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 ch...
christopher/rosetta-code
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...
#VBA
VBA
'Implementation of "set" using the built in Collection datatype. 'A collection can hold any object as item. The examples here are only strings. 'A collection stores item, key pairs. With the key you can retrieve the item. 'The keys are hidden and cannot be changed. No duplicate keys are allowed. 'For the "set" implemen...
Give a code snippet in #VBA 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 cre...
christopher/rosetta-code
http://rosettacode.org/wiki/Wilson_primes_of_order_n
Wilson primes of order n
Definition A Wilson prime of order n is a prime number   p   such that   p2   exactly divides: (n − 1)! × (p − n)! − (− 1)n If   n   is   1,   the latter formula reduces to the more familiar:   (p - n)! + 1   where the only known examples for   p   are   5,   13,   and   563. Task Calculate and show on thi...
#jq
jq
def emit_until(cond; stream): label $out | stream | if cond then break $out else . end;   # For 0 <= $n <= ., factorials[$n] is $n ! def factorials: reduce range(1; .+1) as $n ([1]; .[$n] = $n * .[$n-1]);   def lpad($len): tostring | ($len - length) as $l | (" " * $l)[:$l] + .;   def primes: 2, (range(3; infinit...
Give a code snippet in #jq Definition A Wilson prime of order n is a prime number   p   such that   p2   exactly divides: (n − 1)! × (p − n)! − (− 1)n If   n   is   1,   the latter formula reduces to the more familiar:   (p - n)! + 1   where the only known examples for   p   are   5,   13,   and   563. Ta...
christopher/rosetta-code
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Rust
Rust
use std::path::Path; use std::io::Write; use std::fs::File;   pub struct RGB { r: u8, g: u8, b: u8, }   pub struct PPM { height: u32, width: u32, data: Vec<u8>, }   impl PPM { pub fn new(height: u32, width: u32) -> PPM { let size = 3 * height * width; let buffer = vec![0; siz...
Give a code snippet in #Rust Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
christopher/rosetta-code
http://rosettacode.org/wiki/String_matching
String matching
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#MATLAB_.2F_Octave
MATLAB / Octave
  % 1. Determining if the first string starts with second string strcmp(str1,str2,length(str2)) % 2. Determining if the first string contains the second string at any location ~isempty(strfind(s1,s2)) % 3. Determining if the first string ends with the second string ( (length(str1)>=length(str2)) && strcmp(...
Give a code snippet in #MATLAB_.2F_Octave Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String...
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Mean_angle
Averages/Mean angle
When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle. If one wanted an average direction of the wind over two readings where the first reading was of 350 degrees and the ...
#Perl
Perl
sub Pi () { 3.1415926535897932384626433832795028842 }   sub meanangle { my($x, $y) = (0,0); ($x,$y) = ($x + sin($_), $y + cos($_)) for @_; my $atan = atan2($x,$y); $atan += 2*Pi while $atan < 0; # Ghetto fmod $atan -= 2*Pi while $atan > 2*Pi; $atan; }   sub meandegrees { meanangle( map { $_ * Pi/180 } ...
Give a code snippet in #Perl When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle. If one wanted an average direction of the wind over two readings where the first readi...
christopher/rosetta-code
http://rosettacode.org/wiki/Largest_int_from_concatenated_ints
Largest int from concatenated ints
Task Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer. Use the following two sets of integers as tests   and   show your program output here.   {1, 34, 3, 98, 9, 76, 45, 4}   {54,...
#jq
jq
def largest_int:   def pad(n): . + (n - length) * .[length-1:];   map(tostring) | (map(length) | max) as $max | map([., pad($max)]) | sort_by( .[1] ) | map( .[0] ) | reverse | join("") ;   # Examples: ([1, 34, 3, 98, 9, 76, 45, 4], [54, 546, 548, 60]) | largest_int  
Give a code snippet in #jq Task Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer. Use the following two sets of integers as tests   and   show your program output here.   {1, 34, ...
christopher/rosetta-code
http://rosettacode.org/wiki/Euler_method
Euler method
Euler's method numerically approximates solutions of first-order ordinary differential equations (ODEs) with a given initial value.   It is an explicit method for solving initial value problems (IVPs), as described in the wikipedia page. The ODE has to be provided in the following form: d y ( t ) d t = f...
#Julia
Julia
euler(f::Function, T::Number, t0::Int, t1::Int, h::Int) = collect(begin T += h * f(T); T end for t in t0:h:t1)   # Prints a series of arbitrary values in a tabular form, left aligned in cells with a given width tabular(width, cells...) = println(join(map(s -> rpad(s, width), cells)))   # prints the table according to t...
Give a code snippet in #Julia Euler's method numerically approximates solutions of first-order ordinary differential equations (ODEs) with a given initial value.   It is an explicit method for solving initial value problems (IVPs), as described in the wikipedia page. The ODE has to be provided in the following form: ...
christopher/rosetta-code
http://rosettacode.org/wiki/Matrix_multiplication
Matrix multiplication
Task Multiply two matrices together. They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
#Icon_and_Unicon
Icon and Unicon
  link matrix   procedure main () m1 := [[1,2,3], [4,5,6]] m2 := [[1,2],[3,4],[5,6]] m3 := mult_matrix (m1, m2) write ("Multiply:") write_matrix ("", m1) # first argument is filename, or "" for stdout write ("by:") write_matrix ("", m2) write ("Result: ") write_matrix ("", m3) end  
Give a code snippet in #Icon_and_Unicon Task Multiply two matrices together. They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
christopher/rosetta-code
http://rosettacode.org/wiki/4-rings_or_4-squares_puzzle
4-rings or 4-squares puzzle
4-rings or 4-squares puzzle You are encouraged to solve this task according to the task description, using any language you may know. Task Replace       a, b, c, d, e, f,   and   g       with the decimal digits   LOW   ───►   HIGH such that the sum of the letters inside of each of the four large squares add up to t...
#D
D
import std.stdio;   void main() { fourSquare(1,7,true,true); fourSquare(3,9,true,true); fourSquare(0,9,false,false); }   void fourSquare(int low, int high, bool unique, bool print) { int count;   if (print) { writeln("a b c d e f g"); } for (int a=low; a<=high; ++a) { for (in...
Give a code snippet in #D 4-rings or 4-squares puzzle You are encouraged to solve this task according to the task description, using any language you may know. Task Replace       a, b, c, d, e, f,   and   g       with the decimal digits   LOW   ───►   HIGH such that the sum of the letters inside of each of the fou...
christopher/rosetta-code
http://rosettacode.org/wiki/Accumulator_factory
Accumulator factory
A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed in so far to that accumulat...
#Oz
Oz
declare fun {Acc Init} State = {NewCell Init} in fun {$ X} OldState in {Exchange State OldState} = {Sum OldState X} end end   fun {Sum A B} if {All [A B] Int.is} then A+B else {ToFloat A}+{ToFloat B} end end   fun {ToFloat X} if {Float.is X} then X ...
Give a code snippet in #Oz A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed...
christopher/rosetta-code
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#jq
jq
# Convert a JSON object to a string suitable for use as a CSS style value # e.g: "font-size: 40px; text-align: center;" (without the quotation marks) def to_s: reduce to_entries[] as $pair (""; . + "\($pair.key): \($pair.value); ");   # Defaults: 100%, 100% def svg(width; height): "<svg width='\(width // "100%")' ...
Give a code snippet in #jq Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort
Sorting algorithms/Quicksort
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 ...
#PL.2FI
PL/I
DCL (T(20)) FIXED BIN(31); /* scratch space of length N */   QUICKSORT: PROCEDURE (A,AMIN,AMAX,N) RECURSIVE ; DECLARE (A(*)) FIXED BIN(31); DECLARE (N,AMIN,AMAX) FIXED BIN(31) NONASGN; DECLARE (I,J,IA,IB,IC,PIV) FIXED BIN(31); DECLARE (P,Q) POINTER; DECLARE (AP(1)) ...
Give a code snippet in #PL.2FI 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 s...
christopher/rosetta-code
http://rosettacode.org/wiki/Odd_word_problem
Odd word problem
Task Write a program that solves the odd word problem with the restrictions given below. Description You are promised an input stream consisting of English letters and punctuations. It is guaranteed that: the words (sequence of consecutive letters) are delimited by one and only one punctuation, the stream will...
#Common_Lisp
Common Lisp
(defun odd-word (s) (let ((stream (make-string-input-stream s))) (loop for forwardp = t then (not forwardp) while (if forwardp (forward stream) (funcall (backward stream)))) ))   (defun forward (stream) (let ((ch (read-char stream))) (write-char ch) (if ...
Give a code snippet in #Common_Lisp Task Write a program that solves the odd word problem with the restrictions given below. Description You are promised an input stream consisting of English letters and punctuations. It is guaranteed that: the words (sequence of consecutive letters) are delimited by one and o...
christopher/rosetta-code
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...
#Clojure
Clojure
(slurp "myfile.txt") (slurp "my-utf8-file.txt" "UTF-8")
Give a code snippet in #Clojure 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 inc...
christopher/rosetta-code
http://rosettacode.org/wiki/Probabilistic_choice
Probabilistic choice
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values. The total of all the probabilities should equal one. (Because floating point arithmetic is invol...
#Wren
Wren
import "random" for Random import "/fmt" for Fmt   var letters = ["aleph", "beth", "gimel", "daleth", "he", "waw", "zayin", "heth"] var actual = [0] * 8 var probs = [1/5, 1/6, 1/7, 1/8, 1/9, 1/10, 1/11, 0] var cumProbs = [0] * 8   cumProbs[0] = probs[0] for (i in 1..6) cumProbs[i] = cumProbs[i-1] + probs[i] cumPr...
Give a code snippet in #Wren Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values. The total of all the probabilities should equal one. (Because floa...
christopher/rosetta-code
http://rosettacode.org/wiki/Strip_a_set_of_characters_from_a_string
Strip a set of characters from a string
Task Create a function that strips a set of characters from a string. The function should take two arguments:   a string to be stripped   a string containing the set of characters to be stripped The returned string should contain the first string, stripped of any characters in the second argument: print str...
#Smalltalk
Smalltalk
| stripChars | stripChars := [ :string :chars | string reject: [ :c | chars includes: c ] ]. stripChars value: 'She was a soul stripper. She took my heart!' value: 'aei'.   "'Sh ws soul strppr. Sh took my hrt!'"
Give a code snippet in #Smalltalk Task Create a function that strips a set of characters from a string. The function should take two arguments:   a string to be stripped   a string containing the set of characters to be stripped The returned string should contain the first string, stripped of any characters ...
christopher/rosetta-code
http://rosettacode.org/wiki/Jump_anywhere
Jump anywhere
Imperative programs conditional structures loops local jumps This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports. For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to use these jumps for different...
#Haskell
Haskell
import Control.Monad.Cont   data LabelT r m = LabelT (ContT r m ())   label :: ContT r m (LabelT r m) label = callCC subprog where subprog lbl = let l = LabelT (lbl l) in return l   goto :: LabelT r m -> ContT r m b goto (LabelT l) = const undefined <$> l   runProgram :: Monad m => ContT r m r -> m r runProgram progr...
Give a code snippet in #Haskell Imperative programs conditional structures loops local jumps This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports. For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom...
christopher/rosetta-code
http://rosettacode.org/wiki/Sleep
Sleep
Task Write a program that does the following in this order: Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description. Print "Sleeping..." Sleep the main thread for the given amount of time. ...
#Plain_English
Plain English
To run: Start up. Demonstrate waiting. Wait for the escape key. Shut down.   To demonstrate waiting: Write "How many milliseconds should I wait? " to the console without advancing. Read some milliseconds from the console. Write "Sleeping..." to the console. Wait for the milliseconds. Write "Awake!" to the console.
Give a code snippet in #Plain_English Task Write a program that does the following in this order: Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description. Print "Sleeping..." Sleep the mai...
christopher/rosetta-code
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#ABAP
ABAP
  report zdate. data: lv_month type string, lv_weekday type string, lv_date type string, lv_day type c.   call function 'DATE_COMPUTE_DAY' exporting date = sy-datum importing day = lv_day. select single ltx from t247 into lv_month where spras = sy-langu and mnr = sy-datum+4(2).   select singl...
Give a code snippet in #ABAP This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
christopher/rosetta-code
http://rosettacode.org/wiki/Arithmetic/Integer
Arithmetic/Integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#NSIS
NSIS
Function Arithmetic Push $0 Push $1 Push $2 StrCpy $0 21 StrCpy $1 -2   IntOp $2 $0 + $1 DetailPrint "$0 + $1 = $2" IntOp $2 $0 - $1 DetailPrint "$0 - $1 = $2" IntOp $2 $0 * $1 DetailPrint "$0 * $1 = $2" IntOp $2 $0 / $1 DetailPrint "$0 / $1 = $2" DetailPrint "Rounding is toward negative infinity" IntOp ...
Give a code snippet in #NSIS Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations C...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort
Sorting algorithms/Stooge sort
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 ...
#REXX
REXX
/*REXX program sorts an integer array @. [the first element starts at index zero].*/ parse arg N . /*obtain an optional argument from C.L.*/ if N=='' | N=="," then N=19 /*Not specified? Then use the default.*/ call gen@ ...
Give a code snippet in #REXX 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 sor...
christopher/rosetta-code
http://rosettacode.org/wiki/Factorial_base_numbers_indexing_permutations_of_a_collection
Factorial base numbers indexing permutations of a collection
You need a random arrangement of a deck of cards, you are sick of lame ways of doing this. This task is a super-cool way of doing this using factorial base numbers. The first 25 factorial base numbers in increasing order are: 0.0.0, 0.0.1, 0.1.0, 0.1.1, 0.2.0, 0.2.1, 1.0.0, 1.0.1, 1.1.0, 1.1.1,1.2.0, 1.2.1, 2.0.0, 2.0....
#Phix
Phix
with javascript_semantics function fperm(sequence fbn, omega) integer m=0 for i=1 to length(fbn) do integer g = fbn[i] if g>0 then omega[m+1..m+g+1] = omega[m+g+1]&omega[m+1..m+g] end if m += 1 end for return omega end function function factorial_base_number...
Give a code snippet in #Phix You need a random arrangement of a deck of cards, you are sick of lame ways of doing this. This task is a super-cool way of doing this using factorial base numbers. The first 25 factorial base numbers in increasing order are: 0.0.0, 0.0.1, 0.1.0, 0.1.1, 0.2.0, 0.2.1, 1.0.0, 1.0.1, 1.1.0, 1...
christopher/rosetta-code
http://rosettacode.org/wiki/Optional_parameters
Optional parameters
Task Define a function/method/subroutine which sorts a sequence ("table") of sequences ("rows") of strings ("cells"), by one of the strings. Besides the input to be sorted, it shall have the following optional parameters: ordering A function specifying the ordering of strings; lexicographic by default. column ...
#AppleScript
AppleScript
on sortTable(x) set {sortOrdering, sortColumn, sortReverse} to {sort_lexicographic, 1, false} try set sortOrdering to x's ordering end try try set sortColumn to x's column end try try set sortReverse to x's reverse end try return sortOrdering's sort(x's sequence, sortColumn, sortReverse) end sortTable   s...
Give a code snippet in #AppleScript Task Define a function/method/subroutine which sorts a sequence ("table") of sequences ("rows") of strings ("cells"), by one of the strings. Besides the input to be sorted, it shall have the following optional parameters: ordering A function specifying the ordering of string...
christopher/rosetta-code
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root
Digital root/Multiplicative digital root
The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number, n {\displaystyle n} , is calculated rather like the Digital root except digits are multiplied instead of being added: Set m {\displaystyle m} to n {\displaystyle n} and i {\displaystyle i} to 0 ...
#Go
Go
package main   import "fmt"   // Only valid for n > 0 && base >= 2 func mult(n uint64, base int) (mult uint64) { for mult = 1; mult > 0 && n > 0; n /= uint64(base) { mult *= n % uint64(base) } return }   // Only valid for n >= 0 && base >= 2 func MultDigitalRoot(n uint64, base int) (mp, mdr int) { var m uint64 f...
Give a code snippet in #Go The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number, n {\displaystyle n} , is calculated rather like the Digital root except digits are multiplied instead of being added: Set m {\displaystyle m} to n {\displaystyle n} and i {\d...
christopher/rosetta-code
http://rosettacode.org/wiki/Kaprekar_numbers
Kaprekar numbers
A positive integer is a Kaprekar number if: It is   1     (unity) The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number. Note that a split resulting in a part consisting purely of 0s is not valid, as 0 is not considered positive. ...
#Modula-2
Modula-2
MODULE Kaprekar; FROM FormatString IMPORT FormatString; FROM Terminal IMPORT Write,WriteString,WriteLn,ReadChar;   PROCEDURE kaprekar(n,base : LONGCARD) : BOOLEAN; VAR nn,r,tens : LONGCARD; BEGIN nn := n*n; tens := 1; IF ((nn - n) MOD (base - 1)) # 0 THEN RETURN FALSE END;   WHILE tens < n DO tens :...
Give a code snippet in #Modula-2 A positive integer is a Kaprekar number if: It is   1     (unity) The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number. Note that a split resulting in a part consisting purely of 0s is not valid,...
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Arithmetic_mean
Averages/Arithmetic mean
Task[edit] Write a program to find the mean (arithmetic average) of a numeric vector. In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin...
#Fantom
Fantom
  class Main { static Float average (Float[] nums) { if (nums.size == 0) return 0.0f Float sum := 0f nums.each |num| { sum += num } return sum / nums.size.toFloat }   public static Void main () { [[,], [1f], [1f,2f,3f,4f]].each |Float[] i| { echo ("Average of $i is: " + average(i...
Give a code snippet in #Fantom Task[edit] Write a program to find the mean (arithmetic average) of a numeric vector. In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an est...
christopher/rosetta-code
http://rosettacode.org/wiki/Summarize_primes
Summarize primes
Task Considering in order of length, n, all sequences of consecutive primes, p, from 2 onwards, where p < 1000 and n>0, select those sequences whose sum is prime, and for these display the length of the sequence, the last item in the sequence, and the sum.
#XPL0
XPL0
func IsPrime(N); \Return 'true' if N is a prime number int N, I; [if N <= 1 then return false; for I:= 2 to sqrt(N) do if rem(N/I) = 0 then return false; return true; ];   int Count, N, Sum, Prime; [Text(0, "Prime Prime count sum "); Count:= 0; N:= 0; Sum:= 0; for Prime:= 2 to 1000-1 do if IsPrime(P...
Give a code snippet in #XPL0 Task Considering in order of length, n, all sequences of consecutive primes, p, from 2 onwards, where p < 1000 and n>0, select those sequences whose sum is prime, and for these display the length of the sequence, the last item in the sequence, and the sum.
christopher/rosetta-code
http://rosettacode.org/wiki/Ascending_primes
Ascending primes
Generate and show all primes with strictly ascending decimal digits. Aside: Try solving without peeking at existing solutions. I had a weird idea for generating a prime sieve faster, which needless to say didn't pan out. The solution may be p(r)etty trivial but generating them quickly is at least mildly interesting. T...
#Perl
Perl
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Ascending_primes use warnings; use ntheory qw( is_prime );   print join('', map { sprintf "%10d", $_ } sort { $a <=> $b } grep /./ && is_prime($_), glob join '', map "{$_,}", 1 .. 9) =~ s/.{50}\K/\n/gr;
Give a code snippet in #Perl Generate and show all primes with strictly ascending decimal digits. Aside: Try solving without peeking at existing solutions. I had a weird idea for generating a prime sieve faster, which needless to say didn't pan out. The solution may be p(r)etty trivial but generating them quickly is ...
christopher/rosetta-code
http://rosettacode.org/wiki/Multiplication_tables
Multiplication tables
Task Produce a formatted   12×12   multiplication table of the kind memorized by rote when in primary (or elementary) school. Only print the top half triangle of products.
#AutoIt
AutoIt
#AutoIt Version: 3.2.10.0 $tableupto=12 $table="" for $i = 1 To $tableupto for $j = $i to $tableupto $prod=string($i*$j) if StringLen($prod) == 1 then $prod = " "& $prod EndIf if StringLen($prod) == 2 then $prod = " "& $prod EndIf $table = $table&" "&$prod Next $ta...
Give a code snippet in #AutoIt Task Produce a formatted   12×12   multiplication table of the kind memorized by rote when in primary (or elementary) school. Only print the top half triangle of products.
christopher/rosetta-code
http://rosettacode.org/wiki/Quaternion_type
Quaternion type
Quaternions   are an extension of the idea of   complex numbers. A complex number has a real and complex part,   sometimes written as   a + bi, where   a   and   b   stand for real numbers, and   i   stands for the square root of minus 1. An example of a complex number might be   -3 + 2i,   wher...
#Crystal
Crystal
class Quaternion property a, b, c, d   def initialize(@a : Int64, @b : Int64, @c : Int64, @d : Int64) end   def norm; Math.sqrt(a**2 + b**2 + c**2 + d**2) end def conj; Quaternion.new(a, -b, -c, -d) end def +(n) Quaternion.new(a + n, b, c, d) end def -(n) Quaternion.new(a - n, b, c, d) ...
Give a code snippet in #Crystal Quaternions   are an extension of the idea of   complex numbers. A complex number has a real and complex part,   sometimes written as   a + bi, where   a   and   b   stand for real numbers, and   i   stands for the square root of minus 1. An example of a complex numbe...
christopher/rosetta-code
http://rosettacode.org/wiki/Longest_string_challenge
Longest string challenge
Background This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the challenge and fun part came through th...
#Nanoquery
Nanoquery
import Nanoquery.IO   def longer(a, b) try b[len(a)-1] return false catch return true end end   print "enter filename: " $f = new(File, input())   longest = "" lines = "" for x in $f.read() if longer(x, longest) lines = x longest = x else if !longer(longest, x) lines += "\n" + x end end   println line...
Give a code snippet in #Nanoquery Background This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the cha...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_multiples_of_3_and_5
Sum multiples of 3 and 5
Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
#Tcl
Tcl
# Fairly simple version; only counts by 3 and 5, skipping intermediates proc mul35sum {n} { for {set total [set threes [set fives 0]]} {$threes<$n||$fives<$n} {} { if {$threes<$fives} { incr total $threes incr threes 3 } elseif {$threes>$fives} { incr total $fives incr fives 5 } else { i...
Give a code snippet in #Tcl Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
christopher/rosetta-code
http://rosettacode.org/wiki/Even_or_odd
Even or odd
Task Test whether an integer is even or odd. There is more than one way to solve this task: Use the even and odd predicates, if the language provides them. Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd. Divide i by 2. The remainder equals...
#Futhark
Futhark
  fun main(x: int): bool = (x & 1) == 0  
Give a code snippet in #Futhark Task Test whether an integer is even or odd. There is more than one way to solve this task: Use the even and odd predicates, if the language provides them. Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd. Di...
christopher/rosetta-code
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously
Loop over multiple arrays simultaneously
Task Loop over multiple arrays   (or lists or tuples or whatever they're called in your language)   and display the   i th   element of each. Use your language's   "for each"   loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: ...
#Erlang
Erlang
lists:zipwith3(fun(A,B,C)-> io:format("~s~n",[[A,B,C]]) end, "abc", "ABC", "123").
Give a code snippet in #Erlang Task Loop over multiple arrays   (or lists or tuples or whatever they're called in your language)   and display the   i th   element of each. Use your language's   "for each"   loop if it has one, otherwise iterate through the collection in order with some other loop. For this exa...
christopher/rosetta-code
http://rosettacode.org/wiki/Long_year
Long year
Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
#Terraform
Terraform
module "iso-long-years" { source = "./iso-long-years" start_year = 1995 end_year = 2045 }   output "long-years" { value = module.iso-long-years.long-years }
Give a code snippet in #Terraform Most years have 52 weeks, some have 53, according to ISO8601. Task Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
christopher/rosetta-code
http://rosettacode.org/wiki/Nested_function
Nested function
In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function. Task Write a program consisting of two nested functions that prints t...
#Python
Python
def makeList(separator): counter = 1   def makeItem(item): nonlocal counter result = str(counter) + separator + item + "\n" counter += 1 return result   return makeItem("first") + makeItem("second") + makeItem("third")   print(makeList(". "))
Give a code snippet in #Python In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function. Task Write a program consisting of tw...
christopher/rosetta-code
http://rosettacode.org/wiki/Program_name
Program name
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".) Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A...
#J
J
#!/usr/bin/env jconsole   program =: monad : 0 if. (#ARGV) > 1 do. > 1 { ARGV else. 'Interpreted' end. )   echo 'Program: ', program 0   exit ''
Give a code snippet in #J The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".) Sometimes a multiline shebang is necessary in order to provide the script name...
christopher/rosetta-code
http://rosettacode.org/wiki/Array_length
Array length
Task Determine the amount of elements in an array. As an example use an array holding the strings 'apple' and 'orange'. 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 befo...
#SNOBOL4
SNOBOL4
ar = ARRAY('2,2') ar<1,1> = 'apple' ar<1,2> = 'first' ar<2,1> = 'orange' ar<2,2> = 'second' OUTPUT = IDENT(DATATYPE(ar), 'ARRAY') PROTOTYPE(ar) end
Give a code snippet in #SNOBOL4 Task Determine the amount of elements in an array. As an example use an array holding the strings 'apple' and 'orange'. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter fre...
christopher/rosetta-code
http://rosettacode.org/wiki/Bulls_and_cows
Bulls and cows
Bulls and Cows Task Create a four digit random number from the digits   1   to   9,   without duplication. The program should:   ask for guesses to this number   reject guesses that are malformed   print the score for the guess The score is computed as: The player wins if the guess is the same as the random...
#MATLAB
MATLAB
function BullsAndCows % Plays the game Bulls and Cows as the "game master"   % Create a secret number nDigits = 4; lowVal = 1; highVal = 9; digitList = lowVal:highVal; secret = zeros(1, 4); for k = 1:nDigits idx = randi(length(digitList)); secret(k) = digitList(idx); ...
Give a code snippet in #MATLAB Bulls and Cows Task Create a four digit random number from the digits   1   to   9,   without duplication. The program should:   ask for guesses to this number   reject guesses that are malformed   print the score for the guess The score is computed as: The player wins if the...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort
Sorting algorithms/Pancake sort
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 ...
#C
C
int pancake_sort(int *list, unsigned int length) { //If it's less than 2 long, just return it as sorting isn't really needed... if(length<2) return 0;   int i,a,max_num_pos,moves; moves=0;   for(i=length;i>1;i--) { //Find position of the max number in pos(0) to pos(i) max...
Give a code snippet in #C 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...
christopher/rosetta-code
http://rosettacode.org/wiki/Rep-string
Rep-string
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original. For e...
#Wren
Wren
import "/fmt" for Fmt   var repString = Fn.new { |s| var reps = [] if (s.count < 2) return reps for (c in s) if (c != "0" && c != "1") Fiber.abort("Argument is not a binary string.") var size = s.count for (len in 1..(size/2).floor) { var t = s[0...len] var n = (size/len).floor ...
Give a code snippet in #Wren Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least...
christopher/rosetta-code
http://rosettacode.org/wiki/Compound_data_type
Compound data type
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. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent values. Related task   Enumeration S...
#Visual_Basic_.NET
Visual Basic .NET
Structure Point Public X, Y As Integer End Structure
Give a code snippet in #Visual_Basic_.NET 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. Task Create a compound data type: Point(x,y) A compound data type is one that holds multiple independent ...
christopher/rosetta-code
http://rosettacode.org/wiki/Start_from_a_main_routine
Start from a main routine
Some languages (like Gambas and Visual Basic) support two startup modes.   Applications written in these languages start with an open window that waits for events, and it is necessary to do some trickery to cause a main procedure to run instead.   Data driven or event driven languages may also require similar tricker...
#Raku
Raku
BEGIN {...} # as soon as parsed CHECK {...} # end of compile time INIT {...} # beginning of run time END {...} # end of run time
Give a code snippet in #Raku Some languages (like Gambas and Visual Basic) support two startup modes.   Applications written in these languages start with an open window that waits for events, and it is necessary to do some trickery to cause a main procedure to run instead.   Data driven or event driven languages ma...
christopher/rosetta-code
http://rosettacode.org/wiki/Short-circuit_evaluation
Short-circuit evaluation
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Assume functions   a   and   b   return boolean values,   and further, the execution of function   b   takes considerable resources without side effects, an...
#Rust
Rust
fn a(foo: bool) -> bool { println!("a"); foo }   fn b(foo: bool) -> bool { println!("b"); foo }   fn main() { for i in vec![true, false] { for j in vec![true, false] { println!("{} and {} == {}", i, j, a(i) && b(j)); println!("{} or {} == {}", i, j, a(i) || b(j)); ...
Give a code snippet in #Rust Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Assume functions   a   and   b   return boolean values,   and further, the execution of function   b   takes considerable reso...
christopher/rosetta-code
http://rosettacode.org/wiki/Catalan_numbers
Catalan numbers
Catalan numbers You are encouraged to solve this task according to the task description, using any language you may know. Catalan numbers are a sequence of numbers which can be defined directly: C n = 1 n + 1 ( 2 n n ) = ( 2 n ) ! ( n + 1 ) ! n !  for  n ≥ 0. {\displaystyle C...
#Haskell
Haskell
-- Three infinite lists, corresponding to the three -- definitions in the problem statement.   cats1 :: [Integer] cats1 = (div . product . (enumFromTo . (2 +) <*> (2 *))) <*> (product . enumFromTo 1) <$> [0 ..]   cats2 :: [Integer] cats2 = 1 : fmap (\n -> sum (zipWith (*) (reverse (take n cats2)) cats2)) ...
Give a code snippet in #Haskell Catalan numbers You are encouraged to solve this task according to the task description, using any language you may know. Catalan numbers are a sequence of numbers which can be defined directly: C n = 1 n + 1 ( 2 n n ) = ( 2 n ) ! ( n + 1 ) ! n ! ...
christopher/rosetta-code
http://rosettacode.org/wiki/Feigenbaum_constant_calculation
Feigenbaum constant calculation
Task Calculate the Feigenbaum constant. See   Details in the Wikipedia article:   Feigenbaum constant.
#Groovy
Groovy
class Feigenbaum { static void main(String[] args) { int max_it = 13 int max_it_j = 10 double a1 = 1.0 double a2 = 0.0 double d1 = 3.2 double a   println(" i d") for (int i = 2; i <= max_it; i++) { a = a1 + (a1 - a2) / d1 ...
Give a code snippet in #Groovy Task Calculate the Feigenbaum constant. See   Details in the Wikipedia article:   Feigenbaum constant.
christopher/rosetta-code
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#Go
Go
// Example of composition of anonymous structs package main   import "fmt"   // Two ordinary structs type camera struct { optics, sensor string }   type mobilePhone struct { sim, firmware string }   // Fields are anonymous because only the type is listed. // Also called an embedded field. type cameraPhone struc...
Give a code snippet in #Go Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone...
christopher/rosetta-code
http://rosettacode.org/wiki/Pangram_checker
Pangram checker
Pangram checker You are encouraged to solve this task according to the task description, using any language you may know. A pangram is a sentence that contains all the letters of the English alphabet at least once. For example:   The quick brown fox jumps over the lazy dog. Task Write a function or method to chec...
#VTL-2
VTL-2
10 I=1 20 :I)=0 30 I=I+1 40 #=26>I*20 50 ?="Enter sentence: "; 60 C=$ 70 #=C=13*120 80 C=C<97*32+C-96 90 #=C>27*60 100 :C)=1 110 #=60 120 ?="" 130 I=1 140 N=0 150 N=N+:I) 160 I=I+1 170 #=26>I*150 180 #=N=26*200 190 ?="not "; 200 ?="a pangram"
Give a code snippet in #VTL-2 Pangram checker You are encouraged to solve this task according to the task description, using any language you may know. A pangram is a sentence that contains all the letters of the English alphabet at least once. For example:   The quick brown fox jumps over the lazy dog. Task Wri...
christopher/rosetta-code
http://rosettacode.org/wiki/Stem-and-leaf_plot
Stem-and-leaf plot
Create a well-formatted stem-and-leaf plot from the following data set, where the leaves are the last digits: 12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23 105 63 27 44 105 99 41 128 121 116 125 32 61 37 127 29 113 121 58 114 126 53 11...
#jq
jq
def stem_and_leaf:   # align-right: def right: tostring | (4-length) * " " + .;   sort | .[0] as $min | .[length-1] as $max | "\($min/10|floor|right) | " as $stem | reduce .[] as $d # state: [ stem, string ] ( [ 0, $stem ]; .[0] as $stem | if ($d/10) | floor == $stem ...
Give a code snippet in #jq Create a well-formatted stem-and-leaf plot from the following data set, where the leaves are the last digits: 12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23 105 63 27 44 105 99 41 128 121 116 125 32 61 37 127...
christopher/rosetta-code
http://rosettacode.org/wiki/String_prepend
String prepend
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Lua
Lua
  s = "12345678" s = "0" .. s print(s)
Give a code snippet in #Lua Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Co...
christopher/rosetta-code
http://rosettacode.org/wiki/String_prepend
String prepend
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Objeck
Objeck
class Prepend { function : Main(args : String[]) ~ Nil { s := "world!"; "Hello {$s}"->PrintLine(); } }
Give a code snippet in #Objeck Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations...
christopher/rosetta-code
http://rosettacode.org/wiki/Gamma_function
Gamma function
Task Implement one algorithm (or more) to compute the Gamma ( Γ {\displaystyle \Gamma } ) function (in the real field only). If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function. The Gamma funct...
#Phixmonti
Phixmonti
0.577215664901 var gamma -0.65587807152056 var coeff -0.042002635033944 var quad 0.16653861138228 var qui -0.042197734555571 var theSet   def recigamma var z /# n -- n #/ z 6 power theSet * z 5 power qui * z 4 power quad * z 3 power coeff * z 2 power gamma * z + + + + + enddef   /# without var d...
Give a code snippet in #Phixmonti Task Implement one algorithm (or more) to compute the Gamma ( Γ {\displaystyle \Gamma } ) function (in the real field only). If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in...
christopher/rosetta-code
http://rosettacode.org/wiki/Ultra_useful_primes
Ultra useful primes
An ultra-useful prime is a member of the sequence where each a(n) is the smallest positive integer k such that 2(2n) - k is prime. k must always be an odd number since 2 to any power is always even. Task Find and show here, on this page, the first 10 elements of the sequence. Stretch Find and show the next sev...
#Sidef
Sidef
say(" n k") say("----------")   for n in (1..13) { var t = 2**(2**n) printf("%2d  %d\n", n, {|k| t - k -> is_prob_prime }.first) }
Give a code snippet in #Sidef An ultra-useful prime is a member of the sequence where each a(n) is the smallest positive integer k such that 2(2n) - k is prime. k must always be an odd number since 2 to any power is always even. Task Find and show here, on this page, the first 10 elements of the sequence. Stret...
christopher/rosetta-code
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#Wren
Wren
import "graphics" for Canvas, ImageData, Color import "dome" for Window   class Game { static bmpCreate(name, w, h) { ImageData.create(name, w, h) }   static bmpFill(name, col) { var image = ImageData[name] for (x in 0...image.width) { for (y in 0...image.height) image.pset(x, y, col...
Give a code snippet in #Wren Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
christopher/rosetta-code
http://rosettacode.org/wiki/ABC_problem
ABC problem
ABC problem You are encouraged to solve this task according to the task description, using any language you may know. You are given a collection of ABC blocks   (maybe like the ones you had when you were a kid). There are twenty blocks with two letters on each block. A complete alphabet is guaranteed amongst all sid...
#BQN
BQN
ABC ← { Matches ← ⊑⊸(⊑∘∊¨)˜ /⊣ # blocks matching current letter Others ← <˘∘⍉∘(»⊸≥∨`)∘(≡⌜)/¨<∘⊣ # blocks without current matches 𝕨(×∘≠∘⊢ ◶ ⟨1˙, # if the word is empty, it can be made Matches(×∘≠∘⊣ ◶ ⟨0˙, # if no matching blocks, it cannot ∨´(𝕨 Others⊣) ...
Give a code snippet in #BQN ABC problem You are encouraged to solve this task according to the task description, using any language you may know. You are given a collection of ABC blocks   (maybe like the ones you had when you were a kid). There are twenty blocks with two letters on each block. A complete alphabet ...
christopher/rosetta-code
http://rosettacode.org/wiki/A%2BB
A+B
A+B   ─── a classic problem in programming contests,   it's given so contestants can gain familiarity with the online judging system being used. Task Given two integers,   A and B. Their sum needs to be calculated. Input data Two integers are written in the input stream, separated by space(s): ( − 1000 ≤...
#PL.2FI
PL/I
get (a, b); put (a+b);
Give a code snippet in #PL.2FI A+B   ─── a classic problem in programming contests,   it's given so contestants can gain familiarity with the online judging system being used. Task Given two integers,   A and B. Their sum needs to be calculated. Input data Two integers are written in the input stream, separat...
christopher/rosetta-code
http://rosettacode.org/wiki/Spiral_matrix
Spiral matrix
Task Produce a spiral array. A   spiral array   is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you go around the edges of the array spiraling inwards. For example, given   5,   produce this array: 0 1 2 3 4 15 16 17 18 5 14 23 24 19 6 13 22 21 ...
#Euphoria
Euphoria
function spiral(integer dimension) integer side, curr, curr2 sequence s s = repeat(repeat(0,dimension),dimension) side = dimension curr = 0 for i = 0 to floor(dimension/2) do for j = 1 to side-1 do s[i+1][i+j] = curr -- top curr2 = curr + side-1 s[i+j]...
Give a code snippet in #Euphoria Task Produce a spiral array. A   spiral array   is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you go around the edges of the array spiraling inwards. For example, given   5,   produce this array: 0 1 2 3 4 15 16...
christopher/rosetta-code
http://rosettacode.org/wiki/World_Cup_group_stage
World Cup group stage
It's World Cup season (or at least it was when this page was created)! The World Cup is an international football/soccer tournament that happens every 4 years.   Countries put their international teams together in the years between tournaments and qualify for the tournament based on their performance in other internat...
#J
J
require'stats' outcome=: 3 0,1 1,:0 3 pairs=: (i.4) e."1(2 comb 4) standings=: +/@:>&>,{<"1<"1((i.4) e."1 pairs)#inv"1/ outcome
Give a code snippet in #J It's World Cup season (or at least it was when this page was created)! The World Cup is an international football/soccer tournament that happens every 4 years.   Countries put their international teams together in the years between tournaments and qualify for the tournament based on their pe...
christopher/rosetta-code
http://rosettacode.org/wiki/Dot_product
Dot product
Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1] If implementing the dot ...
#BASIC
BASIC
  100 : 110 REM DOT PRODUCT 120 : 130 REM INITIALIZE VECTORS OF LENGTH N 140 N = 3 150 DIM V1(N): DIM V2(N) 160 FOR I = 1 TO N 170 V1(I) = INT ( RND (1) * 20 - 9.5) 180 V2(I) = INT ( RND (1) * 20 - 9.5) 190 NEXT I 300 : 310 REM CALCULATE THE DOT PRODUCT 320 : 330 FOR I = 1 TO N:DP = DP + V1...
Give a code snippet in #BASIC Task Create a function/use an in-built function, to compute the   dot product,   also known as the   scalar product   of two vectors. If possible, make the vectors of arbitrary length. As an example, compute the dot product of the vectors:   [1,  3, -5]     and   [4, -2, -1...
christopher/rosetta-code
http://rosettacode.org/wiki/Digital_root
Digital root
The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , repeating until X {\displ...
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations   func DRoot(N, B, P); \Return digital root and persistance P real N, B; int P; int S; [P(0):= 0; while N >= B do [S:= 0; repeat S:= S + fix(Mod(N,B)); \sum last digit N:= N/B; \re...
Give a code snippet in #XPL0 The digital root, X {\displaystyle X} , of a number, n {\displaystyle n} , is calculated: find X {\displaystyle X} as the sum of the digits of n {\displaystyle n} find a new X {\displaystyle X} by summing the digits of X {\displaystyle X} , r...
christopher/rosetta-code
http://rosettacode.org/wiki/URL_decoding
URL decoding
This task   (the reverse of   URL encoding   and distinct from   URL parser)   is to provide a function or mechanism to convert an URL-encoded string into its original unencoded form. Test cases   The encoded string   "http%3A%2F%2Ffoo%20bar%2F"   should be reverted to the unencoded form   "http://foo bar/".   Th...
#ooRexx
ooRexx
/* Rexx */ X = 0 url. = '' X = X + 1; url.0 = X; url.X = 'http%3A%2F%2Ffoo%20bar%2F' X = X + 1; url.0 = X; url.X = 'mailto%3A%22Ivan%20Aim%22%20%3Civan%2Eaim%40email%2Ecom%3E' X = X + 1; url.0 = X; url.X = '%6D%61%69%6C%74%6F%3A%22%49%72%6D%61%20%55%73%65%72%22%20%3C%69%72%6D%61%2E%75%73%65%72%40%6D%61%69%6C%...
Give a code snippet in #ooRexx This task   (the reverse of   URL encoding   and distinct from   URL parser)   is to provide a function or mechanism to convert an URL-encoded string into its original unencoded form. Test cases   The encoded string   "http%3A%2F%2Ffoo%20bar%2F"   should be reverted to the unencoded...
christopher/rosetta-code
http://rosettacode.org/wiki/Probabilistic_choice
Probabilistic choice
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values. The total of all the probabilities should equal one. (Because floating point arithmetic is invol...
#Nim
Nim
import tables, random, strformat, times   var start = cpuTime()   const NumTrials = 1_000_000 Probabilities = {"aleph": 1 / 5, "beth": 1 / 6, "gimel": 1 / 7, "daleth": 1 / 8, "he": 1 / 9, "waw": 1 / 10, "zayin": 1 / 11, "heth": 1759 / 27720}.toTable   var samples: CountTable[string]   randomize()...
Give a code snippet in #Nim Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values. The total of all the probabilities should equal one. (Because float...
christopher/rosetta-code