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http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#COBOL
COBOL
identification division. program-id. arbitrary-precision-integers. remarks. Uses opaque libgmp internals that are built into libcob.   data division. working-storage section. 01 gmp-number. 05 mp-alloc usage binary-long. 05 mp-size usage b...
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#JavaScript
JavaScript
function Point(x, y) { this.x = x; this.y = y; } var ZhangSuen = (function () { function ZhangSuen() { } ZhangSuen.image = [" ", " ################# ############# ", " ################## ##...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#EchoLisp
EchoLisp
  ;; special fib's starting with 1 2 3 5 ... (define (fibonacci n) (+ (fibonacci (1- n)) (fibonacci (- n 2)))) (remember 'fibonacci #(1 2))   (define-constant Φ (// (1+ (sqrt 5)) 2)) (define-constant logΦ (log Φ)) ;; find i : fib(i) >= n (define (iFib n) (floor (// (log (+ (* n Φ) 0.5)) logΦ)))   ;; left trim ze...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#Burlesque
Burlesque
  blsq ) 10ro2?^ {1 4 9 16 25 36 49 64 81 100}  
http://rosettacode.org/wiki/Arrays
Arrays
This task is about arrays. For hashes or associative arrays, please see Creating an Associative Array. For a definition and in-depth discussion of what an array is, see Array. Task Show basic array syntax in your language. Basically, create an array, assign a value to it, and retrieve an element   (if available,...
#Eiffel
Eiffel
  class APPLICATION   inherit ARGUMENTS   create make   feature {NONE} -- Initialization make -- Run application. do -- initialize the array, index starts at 1 (not zero) and prefill everything with the letter z create my_static_array.make_filled ("z", 1, 50)   my_static_array.put ("a", 1) my_stati...
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Pascal
Pascal
program complexDemo(output);   const { I experienced some hiccups with -1.0 using GPC (GNU Pascal Compiler) } negativeOne = -1.0;   type line = string(80);   { as per task requirements wrap arithmetic operations into separate functions } function sum(protected x, y: complex): complex; begin sum := x + y end;   func...
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Quackery
Quackery
[ $ "bigrat.qky" loadfile ] now!   [ -2 n->v rot factors witheach [ n->v 1/v v+ ] v0= ] is perfect ( n -> b )   19 bit times [ i^ perfect if [ i^ echo cr ] ]
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#Smalltalk
Smalltalk
agm:y "return the arithmetic-geometric mean agm(x, y) of the receiver (x) and the argument, y. See https://en.wikipedia.org/wiki/Arithmetic-geometric_mean"   |ai an gi gn epsilon delta|   ai := (self + y) / 2. gi := (self * y) sqrt. epsilon := self ulp.   [ an := (ai + gi) / 2...
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Frink
Frink
println[0^0]
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#FutureBasic
FutureBasic
window 1   print 0^0   HandleEvents
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Gambas
Gambas
Public Sub Main()   Print 0 ^ 0   End
http://rosettacode.org/wiki/Zig-zag_matrix
Zig-zag matrix
Task Produce a zig-zag array. A   zig-zag   array is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you zig-zag along the array's   anti-diagonals. For a graphical representation, see   JPG zigzag   (JPG uses such arrays to encode images). For example, gi...
#Ada
Ada
with Ada.Text_IO; use Ada.Text_IO;   procedure Test_Zig_Zag is   type Matrix is array (Positive range <>, Positive range <>) of Natural; function Zig_Zag (Size : Positive) return Matrix is Data : Matrix (1..Size, 1..Size); I, J : Integer := 1; begin Data (1, 1) := 0; for Element in 1.....
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#Arturo
Arturo
yellowstone: function [n][ result: new [1 2 3] present: new [1 2 3] start: new 4 while [n > size result][ candidate: new start while ø [ if all? @[ not? contains? present candidate 1 = gcd @[candidate last result] 1 <> gcd @[can...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#AutoHotkey
AutoHotkey
A := [], in_seq := [] loop 30 { n := A_Index if n <=3 A[n] := n, in_seq[n] := true else while true { s := A_Index if !in_seq[s] && relatively_prime(s, A[n-1]) && !relatively_prime(s, A[n-2]) { A[n] := s in_seq[s] := true break ...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Racket
Racket
#lang racket   (require parser-tools/yacc parser-tools/lex (prefix-in ~ parser-tools/lex-sre))   (define-tokens value-tokens (NUM)) (define-empty-tokens op-tokens (OPEN CLOSE + - * / EOF NEG))   (define lex (lexer [(eof) 'EOF] [whitespace (lex input-port)] [(~or "+" "-" "*" "/") (...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Raku
Raku
sub ev (Str $s --> Numeric) {   grammar expr { token TOP { ^ <sum> $ } token sum { <product> (('+' || '-') <product>)* } token product { <factor> (('*' || '/') <factor>)* } token factor { <unary_minus>? [ <parens> || <literal> ] } token unary_minus { '-' } token paren...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Julia
Julia
import Base.*, Base.+, Base.-, Base./, Base.show, Base.!=, Base.==, Base.<=, Base.<, Base.>, Base.>=, Base.divrem   const z0 = "0" const z1 = "1" const flipordered = (z1 < z0)   mutable struct Z s::String end Z() = Z(z0) Z(z::Z) = Z(z.s)   pairlen(x::Z, y::Z) = max(length(x.s), length(y.s)) tolen(x::Z, n::Int) = (s = x...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Kotlin
Kotlin
// version 1.1.51   class Zeckendorf(x: String = "0") : Comparable<Zeckendorf> {   var dVal = 0 var dLen = 0   private fun a(n: Int) { var i = n while (true) { if (dLen < i) dLen = i val j = (dVal shr (i * 2)) and 3 when (j) { 0, 1 -> retur...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#jq
jq
# The factors, sorted def factors: . as $num | reduce range(1; 1 + sqrt|floor) as $i ([]; if ($num % $i) == 0 then ($num / $i) as $r | if $i == $r then . + [$i] else . + [$i, $r] end else . end | sort) ;   # If the input is a sorted array of distinct non-negative...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Julia
Julia
using Primes   function factorize(n) f = [one(n)] for (p, x) in factor(n) f = reduce(vcat, [f*p^i for i in 1:x], init=f) end f end   function cansum(goal, list) if goal == 0 || list[1] == goal return true elseif length(list) > 1 if list[1] > goal return cansu...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Common_Lisp
Common Lisp
(let ((s (format () "~s" (expt 5 (expt 4 (expt 3 2)))))) (format t "~a...~a, length ~a" (subseq s 0 20) (subseq s (- (length s) 20)) (length s)))
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#D
D
void main() { import std.stdio, std.bigint, std.conv;   auto s = text(5.BigInt ^^ 4 ^^ 3 ^^ 2); writefln("5^4^3^2 = %s..%s (%d digits)", s[0..20], s[$-20..$], s.length); }
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Julia
Julia
  const pixelstring = "00000000000000000000000000000000" * "01111111110000000111111110000000" * "01110001111000001111001111000000" * "01110000111000001110000111000000" * "01110001111000001110000000000000" * "01111111110000001110000000000000" * "01110111100000001110000111000000" * "01110011110011101111001111011100" * "0...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Elena
Elena
import system'routines; import system'collections; import system'text; import extensions; extension op { fibonacci() { if (self < 2) { ^ self } else { ^ (self - 1).fibonacci() + (self - 2).fibonacci() }; }   zeckendorf() { ...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#BQN
BQN
swch ← ≠´{100⥊1«𝕩⥊0}¨1+↕100 ¯1↓∾{𝕩∾@+10}¨•Fmt¨⟨swch,/swch⟩
http://rosettacode.org/wiki/Arrays
Arrays
This task is about arrays. For hashes or associative arrays, please see Creating an Associative Array. For a definition and in-depth discussion of what an array is, see Array. Task Show basic array syntax in your language. Basically, create an array, assign a value to it, and retrieve an element   (if available,...
#Elena
Elena
var staticArray := new int[]{1, 2, 3};
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Perl
Perl
use Math::Complex; my $a = 1 + 1*i; my $b = 3.14159 + 1.25*i;   print "$_\n" foreach $a + $b, # addition $a * $b, # multiplication -$a, # negation 1 / $a, # multiplicative inverse ~$a; # complex conjugate
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Racket
Racket
  -> (* 1/7 14) 2  
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#SQL
SQL
WITH rec (rn, a, g, diff) AS ( SELECT 1, 1, 1/SQRT(2), 1 - 1/SQRT(2) FROM dual UNION ALL SELECT rn + 1, (a + g)/2, SQRT(a * g), (a + g)/2 - SQRT(a * g) FROM rec WHERE diff > 1e-38 ) SELECT * FROM rec WHERE diff <= 1e-38 ;
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#Standard_ML
Standard ML
  fun agm(a, g) = let fun agm'(a, g, eps) = if Real.abs(a-g) < eps then a else agm'((a+g)/2.0, Math.sqrt(a*g), eps) in agm'(a, g, 1e~15) end;  
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Go
Go
package main   import ( "fmt" "math" "math/big" "math/cmplx" )   func main() { fmt.Println("float64: ", math.Pow(0, 0)) var b big.Int fmt.Println("big integer:", b.Exp(&b, &b, nil)) fmt.Println("complex: ", cmplx.Pow(0, 0)) }
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Groovy
Groovy
println 0**0
http://rosettacode.org/wiki/Zig-zag_matrix
Zig-zag matrix
Task Produce a zig-zag array. A   zig-zag   array is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you zig-zag along the array's   anti-diagonals. For a graphical representation, see   JPG zigzag   (JPG uses such arrays to encode images). For example, gi...
#Agena
Agena
# zig-zag matrix   makeZigZag := proc( n :: number ) :: table is   local move := proc( x :: number, y :: number, upRight :: boolean ) is if y = n then upRight := not upRight; x := x + 1 elif x = 1 then upRight := not upRight; y := y + 1 else ...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#C
C
#include <stdbool.h> #include <stdio.h> #include <stdlib.h>   typedef struct lnode_t { struct lnode_t *prev; struct lnode_t *next; int v; } Lnode;   Lnode *make_list_node(int v) { Lnode *node = malloc(sizeof(Lnode)); if (node == NULL) { return NULL; } node->v = v; node->prev = NU...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#REXX
REXX
/*REXX program evaluates an infix─type arithmetic expression and displays the result.*/ nchars = '0123456789.eEdDqQ' /*possible parts of a number, sans ± */ e='***error***'; $=" "; doubleOps= '&|*/'; z= /*handy─dandy variables.*/ parse arg x 1 ox1; if x='' then call serr "...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Nim
Nim
type Zeckendorf = object dVal: Natural dLen: Natural   const Dig = ["00", "01", "10"] Dig1 = ["", "1", "10"]   # Forward references. func b(z: var Zeckendorf; pos: Natural) func inc(z: var Zeckendorf)     func a(z: var Zeckendorf; n: Natural) = var i = n while true:   if z.dLen < i: z.dLen = i let j...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Kotlin
Kotlin
import java.util.ArrayList import kotlin.math.sqrt   object ZumkellerNumbers { @JvmStatic fun main(args: Array<String>) { var n = 1 println("First 220 Zumkeller numbers:") run { var count = 1 while (count <= 220) { if (isZumkeller(n)) { ...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Dart
Dart
import 'dart:math' show pow;   int fallingPowers(int base) => base == 1 ? 1 : pow(base, fallingPowers(base - 1));   void main() { final exponent = fallingPowers(4), s = BigInt.from(5).pow(exponent).toString(); print('First twenty: ${s.substring(0, 20)}'); print('Last twenty: ${s.substring(s.len...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#dc
dc
[5432.dc]sz   5 4 3 2 ^ ^ ^ sy [y = 5 ^ 4 ^ 3 ^ 2]sz ly Z sc [c = length of y]sz [ First 20 digits: ]P ly 10 lc 20 - ^ / p sz [y / (10 ^ (c - 20))]sz [ Last 20 digits: ]P ly 10 20 ^ % p sz [y % (10 ^ 20)]sz [Number of digits: ]P lc p sz
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Kotlin
Kotlin
// version 1.1.2   class Point(val x: Int, val y: Int)   val image = arrayOf( " ", " ################# ############# ", " ################## ################ ", " ################### #######...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Elixir
Elixir
defmodule Zeckendorf do def number do Stream.unfold(0, fn n -> zn_loop(n) end) end   defp zn_loop(n) do bin = Integer.to_string(n, 2) if String.match?(bin, ~r/11/), do: zn_loop(n+1), else: {bin, n+1} end end   Zeckendorf.number |> Enum.take(21) |> Enum.with_index |> Enum.each(fn {zn, i} -> IO.puts "...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#C
C
#include <stdio.h>   int main() { char is_open[100] = { 0 }; int pass, door;   /* do the 100 passes */ for (pass = 0; pass < 100; ++pass) for (door = pass; door < 100; door += pass+1) is_open[door] = !is_open[door];   /* output the result */ for (door = 0; door < 100; ++door) printf("door #%d ...
http://rosettacode.org/wiki/Arrays
Arrays
This task is about arrays. For hashes or associative arrays, please see Creating an Associative Array. For a definition and in-depth discussion of what an array is, see Array. Task Show basic array syntax in your language. Basically, create an array, assign a value to it, and retrieve an element   (if available,...
#Elixir
Elixir
ret = {:ok, "fun", 3.1415}
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Phix
Phix
-- demo\rosetta\ArithComplex.exw with javascript_semantics include complex.e complex a = complex_new(1,1), -- (or just {1,1}) b = complex_new(3.14159,1.25), c = complex_new(1,0), d = complex_new(0,1) printf(1,"a = %s\n",{complex_sprint(a)}) printf(1,"b = %s\n",{complex_sprint(b)}) printf(1,"c =...
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Raku
Raku
(2..2**19).hyper.map: -> $candidate { my $sum = 1 / $candidate; for 2 .. ceiling(sqrt($candidate)) -> $factor { if $candidate %% $factor { $sum += 1 / $factor + 1 / ($candidate / $factor); } } if $sum.nude[1] == 1 { say "Sum of reciprocal factors of $candidate = $sum ...
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#Stata
Stata
mata   real scalar agm(real scalar a, real scalar b) { real scalar c do { c=0.5*(a+b) b=sqrt(a*b) a=c } while (a-b>1e-15*a) return(0.5*(a+b)) }   agm(1,1/sqrt(2)) end
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#Swift
Swift
import Darwin   enum AGRError : Error { case undefined }   func agm(_ a: Double, _ g: Double, _ iota: Double = 1e-8) throws -> Double { var a = a var g = g var a1: Double = 0 var g1: Double = 0   guard a * g >= 0 else { throw AGRError.undefined }   while abs(a - g) > iota { a1 = (a + g) / 2 g1 = sqrt(a * ...
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#GW-BASIC
GW-BASIC
PRINT 0^0
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Haskell
Haskell
import Data.Complex   main = do print $ 0 ^ 0 print $ 0.0 ^ 0 print $ 0 ^^ 0 print $ 0 ** 0 print $ (0 :+ 0) ^ 0 print $ (0 :+ 0) ** (0 :+ 0)
http://rosettacode.org/wiki/Zig-zag_matrix
Zig-zag matrix
Task Produce a zig-zag array. A   zig-zag   array is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you zig-zag along the array's   anti-diagonals. For a graphical representation, see   JPG zigzag   (JPG uses such arrays to encode images). For example, gi...
#ALGOL_68
ALGOL 68
PROC zig zag = (INT n)[,]INT: ( PROC move = (REF INT i, j)VOID: ( IF j < n THEN i := ( i <= 1 | 1 | i-1 ); j +:= 1 ELSE i +:= 1 FI );   [n, n]INT a; INT x:=LWB a, y:=LWB a;   FOR v FROM 0 TO n**2-1 DO a[y, x] := v; IF ODD (x...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#C.2B.2B
C++
#include <iostream> #include <numeric> #include <set>   template <typename integer> class yellowstone_generator { public: integer next() { n2_ = n1_; n1_ = n_; if (n_ < 3) { ++n_; } else { for (n_ = min_; !(sequence_.count(n_) == 0 && std::gcd(...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#AArch64_Assembly
AArch64 Assembly
  /* ARM assembly AARCH64 Raspberry PI 3B */ /* program yahoosearch64.s */   /* access RosettaCode.org and data extract */ /* use openssl for access to port 443 */ /* test openssl : package libssl-dev */ /*******************************************/ /* Constantes file */ /************...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Ruby
Ruby
$op_priority = {"+" => 0, "-" => 0, "*" => 1, "/" => 1}   class TreeNode OP_FUNCTION = { "+" => lambda {|x, y| x + y}, "-" => lambda {|x, y| x - y}, "*" => lambda {|x, y| x * y}, "/" => lambda {|x, y| x / y}} attr_accessor :info, :left, :right   def initialize(info) @info = info end   def ...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Perl
Perl
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Zeckendorf_arithmetic use warnings;   for ( split /\n/, <<END ) # test cases 1 + 1 10 + 10 10100 + 1010 10100 - 1010 10100 * 1010 100010 * 100101 10100 / 1010 101000 / 1000 100001000001 / 100010 100001000001 / 100101 END { my ($left, $...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Lobster
Lobster
import std   // Derived from Julia and Python versions   def get_divisors(n: int) -> [int]: var i = 2 let d = [1, n] let limit = sqrt(n) while i <= limit: if n % i == 0: let j = n / i push(d,i) if i != j: push(d,j) i += 1 return d  ...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
ClearAll[ZumkellerQ] ZumkellerQ[n_] := Module[{d = Divisors[n], t, ds, x}, ds = Total[d]; If[Mod[ds, 2] == 1, False , t = CoefficientList[Product[1 + x^i, {i, d}], x]; t[[1 + ds/2]] > 0 ] ]; i = 1; res = {}; While[Length[res] < 220, r = ZumkellerQ[i]; If[r, AppendTo[res, i]]; i++; ]...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Delphi
Delphi
  program Arbitrary_precision_integers;   {$APPTYPE CONSOLE}   uses System.SysUtils, Velthuis.BigIntegers;   var value: BigInteger; result: string;   begin value := BigInteger.pow(3, 2); value := BigInteger.pow(4, value.AsInteger); value := BigInteger.pow(5, value.AsInteger); result := value.tostring; ...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#E
E
? def value := 5**(4**(3**2)); null ? def decimal := value.toString(10); null ? decimal(0, 20) # value: "62060698786608744707"   ? decimal(decimal.size() - 20) # value: "92256259918212890625"   ? decimal.size() # value: 183231
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Lua
Lua
function zhangSuenThin(img) local dirs={ { 0,-1}, { 1,-1}, { 1, 0}, { 1, 1}, { 0, 1}, {-1, 1}, {-1, 0}, {-1,-1}, { 0,-1}, }   local black=1 local white=0   function A(x, y) local c=0 local current=img[y+dirs[1][2...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#F.23
F#
let fib = Seq.unfold (fun (x, y) -> Some(x, (y, x + y))) (1,2)   let zeckendorf n = if n = 0 then ["0"] else let folder k state = let (n, z) = (fst state), (snd state) if n >= k then (n - k, "1" :: z) else (n, "0" :: z) let fb = fib |> Seq.takeWhile (fun i -> ...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#C.23
C#
namespace ConsoleApplication1 { using System; class Program { static void Main(string[] args) { bool[] doors = new bool[100];   //Close all doors to start. for (int d = 0; d < 100; d++) doors[d] = false;   //For each pass... for (in...
http://rosettacode.org/wiki/Arrays
Arrays
This task is about arrays. For hashes or associative arrays, please see Creating an Associative Array. For a definition and in-depth discussion of what an array is, see Array. Task Show basic array syntax in your language. Basically, create an array, assign a value to it, and retrieve an element   (if available,...
#Erlang
Erlang
  %% Create a fixed-size array with entries 0-9 set to 'undefined' A0 = array:new(10). 10 = array:size(A0).   %% Create an extendible array and set entry 17 to 'true', %% causing the array to grow automatically A1 = array:set(17, true, array:new()). 18 = array:size(A1).   %% Read back a stored value t...
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#PicoLisp
PicoLisp
(load "@lib/math.l")   (de addComplex (A B) (cons (+ (car A) (car B)) # Real (+ (cdr A) (cdr B)) ) ) # Imag   (de mulComplex (A B) (cons (- (*/ (car A) (car B) 1.0) (*/ (cdr A) (cdr B) 1.0) ) (+ (*/ (car A) (cdr B) 1.0) (*/ (cdr A) (car B) 1.0)...
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#PL.2FI
PL/I
/* PL/I complex numbers may be integer or floating-point. */ /* In this example, the variables are floating-pint. */ /* For integer variables, change 'float' to 'fixed binary' */   declare (a, b) complex float; a = 2+5i; b = 7-6i;   put skip list (a+b); put skip list (a - b); put skip list (a*b); put skip list (...
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#REXX
REXX
/*REXX program implements a reasonably complete rational arithmetic (using fractions).*/ L=length(2**19 - 1) /*saves time by checking even numbers. */ do j=2 by 2 to 2**19 - 1; s=0 /*ignore unity (which can't be perfect)*/ mostDivs=eDivs(j); @= ...
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#Tcl
Tcl
proc agm {a b} { set old_b [expr {$b<0?inf:-inf}] while {$a != $b && $b != $old_b} { set old_b $b lassign [list [expr {0.5*($a+$b)}] [expr {sqrt($a*$b)}]] a b } return $a }   puts [agm 1 [expr 1/sqrt(2)]]
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#TI-83_BASIC
TI-83 BASIC
1→A:1/sqrt(2)→G While abs(A-G)>e-15 (A+G)/2→B sqrt(AG)→G:B→A End A
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#HolyC
HolyC
F64 a = 0 ` 0; Print("0 ` 0 = %5.3f\n", a);
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Icon_and_Unicon
Icon and Unicon
procedure main() write(0^0) end
http://rosettacode.org/wiki/Zig-zag_matrix
Zig-zag matrix
Task Produce a zig-zag array. A   zig-zag   array is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you zig-zag along the array's   anti-diagonals. For a graphical representation, see   JPG zigzag   (JPG uses such arrays to encode images). For example, gi...
#ALGOL_W
ALGOL W
begin % zig-zag matrix %  % z is returned holding a zig-zag matrix of order n, z must be at least n x n % procedure makeZigZag ( integer value n  ; integer array z( *, * ) ) ; begin procedure move ; begin if y = n then begin ...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#D
D
import std.numeric; import std.range; import std.stdio;   class Yellowstone { private bool[int] sequence_; private int min_ = 1; private int n_ = 0; private int n1_ = 0; private int n2_ = 0;   public this() { popFront(); }   public bool empty() { return false; }   ...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#ARM_Assembly
ARM Assembly
  /* ARM assembly Raspberry PI */ /* program yahoosearch.s */ /* access RosettaCode.org and data extract */ /* use openssl for access to port 443 */ /* test openssl : package libssl-dev */   /* REMARK 1 : this program use routines in a include file see task Include a file language arm assembly for t...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Rust
Rust
//! Simple calculator parser and evaluator     /// Binary operator #[derive(Debug)] pub enum Operator { Add, Substract, Multiply, Divide }   /// A node in the tree #[derive(Debug)] pub enum Node { Value(f64), SubNode(Box<Node>), Binary(Operator, Box<Node>,Box<Node>), }   /// parse a string i...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Phix
Phix
with javascript_semantics sequence fib = {1,1} function zeckendorf(atom n) -- Same as Zeckendorf_number_representation#Phix atom r = 0 while fib[$]<n do fib &= fib[$] + fib[$-1] end while integer k = length(fib) while k>2 and n<fib[k] do k -= 1 end while for i=k to 2 by...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Nim
Nim
import math, strutils   template isEven(n: int): bool = (n and 1) == 0 template isOdd(n: int): bool = (n and 1) != 0     func getDivisors(n: int): seq[int] = result = @[1, n] for i in 2..sqrt(n.toFloat).int: if n mod i == 0: let j = n div i result.add i if i != j: result.add j     func isPartS...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Pascal
Pascal
program zumkeller; //https://oeis.org/A083206/a083206.txt {$IFDEF FPC} {$MODE DELPHI} {$OPTIMIZATION ON,ALL} {$COPERATORS ON} // {$O+,I+} {$ELSE} {$APPTYPE CONSOLE} {$ENDIF} uses sysutils {$IFDEF WINDOWS},Windows{$ENDIF} ; //###################################################################### //prime decom...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#EchoLisp
EchoLisp
  ;; to save space and time, we do'nt stringify Ω = 5^4^3^2 , ;; but directly extract tail and head and number of decimal digits   (lib 'bigint) ;; arbitrary size integers   (define e10000 (expt 10 10000)) ;; 10^10000   (define (last-n big (n 20)) (string-append "..." (number->string (modulo big (expt 10 n)))))   (defi...
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
nB[mat_] := Delete[mat // Flatten, 5] // Total;   nA[mat_] := Module[{l}, l = Flatten[mat][[{2, 3, 6, 9, 8, 7, 4, 1, 2}]]; Total[Map[If[#[[1]] == 0 && #[[2]] == 1, 1, 0] &, Partition[l, 2, 1]]] ];   iW1[mat_] := Module[{l = Flatten[mat]}, If[Apply[Times, l[[{2, 6, 8}]]] + Apply[Times, l[[{4, 6, 8}...
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Nim
Nim
import math, sequtils, strutils   type Bit = 0..1 BitMatrix = seq[seq[Bit]] # Two-dimensional array of 0/1. Neighbors = array[2..9, Bit] # Neighbor values.   const Symbols = [Bit(0): '.', Bit(1): '#']     func toBitMatrix(s: openArray[string]): BitMatrix = ## Convert an array of 01 strings into a BitMatrix...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Factor
Factor
USING: formatting kernel locals make math sequences ;   :: fib<= ( n -- seq ) 1 2 [ [ dup n <= ] [ 2dup + [ , ] 2dip ] while drop , ] { } make ;   :: zeck ( n -- str ) 0 :> s! n fib<= <reversed> [ dup s + n <= [ s + s! 49 ] [ drop 48 ] if ] "" map-as ;   21 <iota> [ dup zeck "%2d: %6s\n" printf ] each
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Forth
Forth
: fib<= ( n -- n ) >r 0 1 BEGIN dup r@ <= WHILE tuck + REPEAT drop rdrop ;   : z. ( n -- ) dup fib<= dup . - BEGIN ?dup WHILE dup fib<= dup [char] + emit space . - REPEAT ;   : tab 9 emit ;   : zeckendorf ( -- ) 21 0 DO cr i 2 .r tab i z. LOOP ;
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#C.2B.2B
C++
#include <iostream>   int main() { bool is_open[100] = { false };   // do the 100 passes for (int pass = 0; pass < 100; ++pass) for (int door = pass; door < 100; door += pass+1) is_open[door] = !is_open[door];   // output the result for (int door = 0; door < 100; ++door) std::cout << "door #" <<...
http://rosettacode.org/wiki/Arrays
Arrays
This task is about arrays. For hashes or associative arrays, please see Creating an Associative Array. For a definition and in-depth discussion of what an array is, see Array. Task Show basic array syntax in your language. Basically, create an array, assign a value to it, and retrieve an element   (if available,...
#ERRE
ERRE
DIM A%[100]  ! integer array DIM S$[50]  ! string array DIM R[50]  ! real array DIM R#[70]  ! long real array
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Pop11
Pop11
lvars a = 1.0 +: 1.0, b = 2.0 +: 5.0 ; a+b => a*b => 1/a => a-b => a-a => a/b => a/a =>   ;;; The same, but using exact values 1 +: 1 -> a; 2 +: 5 -> b; a+b => a*b => 1/a => a-b => a-a => a/b => a/a =>
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Ruby
Ruby
  for candidate in 2 .. 2**19 sum = Rational(1, candidate) for factor in 2 .. Integer.sqrt(candidate) if candidate % factor == 0 sum += Rational(1, factor) + Rational(1, candidate / factor) end end if sum.denominator == 1 puts "Sum of recipr. factors of %d = %d exactly %s" % [candid...
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#UNIX_Shell
UNIX Shell
function agm { float a=$1 g=$2 eps=${3:-1e-11} tmp while (( abs(a-g) > eps )); do print "debug: a=$a\tg=$g" tmp=$(( (a+g)/2.0 )) g=$(( sqrt(a*g) )) a=$tmp done echo $a }   agm $((1/sqrt(2))) 1
http://rosettacode.org/wiki/Arithmetic-geometric_mean
Arithmetic-geometric mean
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Write a function to compute the arithmetic-geomet...
#VBA
VBA
Private Function agm(a As Double, g As Double, Optional tolerance As Double = 0.000000000000001) As Double Do While Abs(a - g) > tolerance tmp = a a = (a + g) / 2 g = Sqr(tmp * g) Debug.Print a Loop agm = a End Function Public Sub main() Debug.Print agm(1, 1 / Sqr(2)) End...
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#J
J
0 ^ 0 1
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Java
Java
System.out.println(Math.pow(0, 0));
http://rosettacode.org/wiki/Zig-zag_matrix
Zig-zag matrix
Task Produce a zig-zag array. A   zig-zag   array is a square arrangement of the first   N2   natural numbers,   where the numbers increase sequentially as you zig-zag along the array's   anti-diagonals. For a graphical representation, see   JPG zigzag   (JPG uses such arrays to encode images). For example, gi...
#APL
APL
zz ← {⍵⍴⎕IO-⍨⍋⊃,/{(2|⍴⍵):⌽⍵⋄⍵}¨(⊂w)/¨⍨w{↓⍵∘.=⍨∪⍵}+/[1]⍵⊤w←⎕IO-⍨⍳×/⍵} ⍝ General zigzag (any rectangle) zzSq ← {zz,⍨⍵} ⍝ Square zigzag zzSq 5 0 1 5 6 14 2 4 7 13 15 3 8 12 16 21 9 11 17 20 22 10 18 19 23 24
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#Delphi
Delphi
  program Yellowstone_sequence;   {$APPTYPE CONSOLE}   uses System.SysUtils, Boost.Generics.Collection, Boost.Process;   function gdc(x, y: Integer): Integer; begin while y <> 0 do begin var tmp := x; x := y; y := tmp mod y; end; Result := x; end;   function Yellowstone(n: Integer): TArray<Int...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#AutoHotkey
AutoHotkey
test: yahooSearch("test", 1) yahooSearch("test", 2) return   yahooSearch(query, page) { global start := ((page - 1) * 10) + 1 filedelete, search.txt urldownloadtofile, % "http://search.yahoo.com/search?p=" . query . "&b=" . start, search.txt fileread, content, search.txt reg = <a class="yschttl spt" href=...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Scala
Scala
  package org.rosetta.arithmetic_evaluator.scala   object ArithmeticParser extends scala.util.parsing.combinator.RegexParsers {   def readExpression(input: String) : Option[()=>Int] = { parseAll(expr, input) match { case Success(result, _) => Some(result) case other => println(other) ...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#PicoLisp
PicoLisp
(seed (in "/dev/urandom" (rd 8)))   (de unpad (Lst) (while (=0 (car Lst)) (pop 'Lst) ) Lst )   (de numz (N) (let Fibs (1 1) (while (>= N (+ (car Fibs) (cadr Fibs))) (push 'Fibs (+ (car Fibs) (cadr Fibs))) ) (make (for I (uniq Fibs) (if (> I N) (lin...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Python
Python
import copy   class Zeckendorf: def __init__(self, x='0'): q = 1 i = len(x) - 1 self.dLen = int(i / 2) self.dVal = 0 while i >= 0: self.dVal = self.dVal + (ord(x[i]) - ord('0')) * q q = q * 2 i = i -1   def a(self, n): i = n ...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Perl
Perl
use strict; use warnings; use feature 'say'; use ntheory <is_prime divisor_sum divisors vecsum forcomb lastfor>;   sub in_columns { my($columns, $values) = @_; my @v = split ' ', $values; my $width = int(80/$columns); printf "%${width}d"x$columns."\n", @v[$_*$columns .. -1+(1+$_)*$columns] for 0..-1+@v/...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Elixir
Elixir
defmodule Arbitrary do def pow(_,0), do: 1 def pow(b,e) when e > 0, do: pow(b,e,1)   defp pow(b,1,acc), do: acc * b defp pow(b,p,acc) when rem(p,2)==0, do: pow(b*b,div(p,2),acc) defp pow(b,p,acc), do: pow(b,p-1,acc*b)   def test do s = pow(5,pow(4,pow(3,2))) |> to_string l = String.length(s) pre...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Emacs_Lisp
Emacs Lisp
(let* ((integer-width (* 65536 16)) ; raise bignum limit from 65536 bits to avoid overflow error (answer (number-to-string (expt 5 (expt 4 (expt 3 2))))) (length (length answer))) (message "%s has %d digits" (if (> length 40) (format "%s...%s" (substring answer 0 20) (subst...
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Perl
Perl
use List::Util qw(sum min);   $source = <<'END'; ............................................................ ..#################...................#############......... ..##################...............################......... ..###################............##################......... ..########.....#######........
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Fortran
Fortran
F(N) = ((1 + SQRT(5))**N - (1 - SQRT(5))**N)/(SQRT(5)*2**N)