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http://rosettacode.org/wiki/Checkpoint_synchronization
Checkpoint synchronization
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st...
#Ada
Ada
with Ada.Calendar; use Ada.Calendar; with Ada.Numerics.Float_Random; with Ada.Text_IO; use Ada.Text_IO;   procedure Test_Checkpoint is   package FR renames Ada.Numerics.Float_Random; No_Of_Cubicles: constant Positive := 3; -- That many workers can work in parallel No_Of_Worker...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#EchoLisp
EchoLisp
  (define my-collection ' ( 🌱 ☀️ ☔️ )) (set! my-collection (cons '🎥 my-collection)) (set! my-collection (cons '🐧 my-collection)) my-collection → (🐧 🎥 🌱 ☀️ ☔️)   ;; save it (local-put 'my-collection) → my-collection  
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#Lambdatalk
Lambdatalk
    {def comb {def comb.r {lambda {:m :n :N} {if {= :m 0} then {A.new {A.new}} else {if {= :n :N} then {A.new} else {A.concat {A.map {{lambda {:n :rest} {A.addfirst! :n :rest}} :n} {comb.r {- :m 1} {+ :n 1} :N}} {comb.r :m {+ :n 1} :N}}}}}} {lambda {:m :n} {...
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#PowerShell
PowerShell
# standard if if (condition) { # ... }   # if-then-else if (condition) { # ... } else { # ... }   # if-then-elseif-else if (condition) { # ... } elseif (condition2) { # ... } else { # ... }
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Z80_Assembly
Z80 Assembly
ld hl,&8000 ;This is a comment
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#zig
zig
// This is a normal comment in Zig /// This is a documentation comment in Zig (for the following line)
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#zkl
zkl
x=1; // comment ala C++ x=2; # ala scripts /* ala C, these comments are parsed (also ala C) */ /* can /* be */ nested */ #if 0 also ala C (and parsed) #endif #<<<# "here" comment, unparsed #<<<#
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#Ada
Ada
with Ada.Text_IO, Mod_Inv;   procedure Chin_Rema is N: array(Positive range <>) of Positive := (3, 5, 7); A: array(Positive range <>) of Positive := (2, 3, 2); Tmp: Positive; Prod: Positive := 1; Sum: Natural := 0;   begin for I in N'Range loop Prod := Prod * N(I); end loop;   for I ...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#J
J
a=: {{)v if.3=y do.1729 return.end. m=. z=. 2^y-4 f=. 6 12,9*2^}.i.y-1 while.do. uf=.1+f*m if.*/1 p: uf do. */x:uf return.end. m=.m+z end. }}
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Java
Java
  import java.math.BigInteger; import java.util.ArrayList; import java.util.List;   public class ChernicksCarmichaelNumbers {   public static void main(String[] args) { for ( long n = 3 ; n < 10 ; n++ ) { long m = 0; boolean foundComposite = true; List<Long> factors = nul...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#C.2B.2B
C++
#include <vector> #include <iostream>   using namespace std;   int chowla(int n) { int sum = 0; for (int i = 2, j; i * i <= n; i++) if (n % i == 0) sum += i + (i == (j = n / i) ? 0 : j); return sum; }   vector<bool> sieve(int limit) { // True denotes composite, false denotes prime. // Only interested in odd numb...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#J
J
chget=: {{(0;1;1;1) {:: y}}   chset=: {{ 'A B'=.;y 'C D'=.B 'E F'=.D <A;<C;<E;<<.x }}   ch0=: {{ if.0=#y do.y=.;:'>:' end. NB. replace empty gerund with increment 0 chset y`:6^:2`'' }}   apply=: `:6   chNext=: {{(1+chget y) chset y}}   chAdd=: {{(x +&chget y) chset y}} chSub=: {{(x -&chget y) chset y}} chMu...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Java
Java
package lvijay;   import java.util.concurrent.atomic.AtomicInteger; import java.util.function.Function;   public class Church { public static interface ChurchNum extends Function<ChurchNum, ChurchNum> { }   public static ChurchNum zero() { return f -> x -> x; }   public static ChurchNum next...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Delphi
Delphi
program SampleClass;   {$APPTYPE CONSOLE}   type TMyClass = class private FSomeField: Integer; // by convention, fields are usually private and exposed as properties public constructor Create; destructor Destroy; override; procedure SomeMethod; property SomeField: Integer read FSomeField write...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Plain_English
Plain English
To run: Start up. Show some example Cistercian numbers. Wait for the escape key. Shut down.   To show some example Cistercian numbers: Put the screen's left plus 1 inch into the context's spot's x. Clear the screen to the lightest gray color. Use the black color. Use the fat pen. Draw 0. Draw 1. Draw 20. Draw 300. Draw...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Python
Python
# -*- coding: utf-8 -*- """ Some UTF-8 chars used:   ‾ 8254 203E &oline; OVERLINE ┃ 9475 2503 BOX DRAWINGS HEAVY VERTICAL ╱ 9585 2571 BOX DRAWINGS LIGHT DIAGONAL UPPER RIGHT TO LOWER LEFT ╲ 9586 2572 BOX DRAWINGS LIGHT DIAGONAL UPPER LEFT TO LOWER RIGHT ◸ 9720 25F8 UPPER LEFT TRIANGLE ◹ 9721 25F9 UPPER RIGHT ...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. 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 Provide a function to find the closest two p...
#FreeBASIC
FreeBASIC
  Dim As Integer i, j Dim As Double minDist = 1^30 Dim As Double x(9), y(9), dist, mini, minj   Data 0.654682, 0.925557 Data 0.409382, 0.619391 Data 0.891663, 0.888594 Data 0.716629, 0.996200 Data 0.477721, 0.946355 Data 0.925092, 0.818220 Data 0.624291, 0.142924 Data 0.211332, 0.221507 Data 0.293786, 0.691701...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#M2000_Interpreter
M2000 Interpreter
  Dim Base 0, A(10) For i=0 to 9 { a(i)=lambda i -> i**2 } For i=0 to 9 { Print a(i)() }  
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Maple
Maple
> L := map( i -> (() -> i^2), [seq](1..10) ): > seq( L[i](),i=1..10); 1, 4, 9, 16, 25, 36, 49, 64, 81, 100 > L[4](); 16  
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#REXX
REXX
/*REXX program finds & displays circular primes (with a title & in a horizontal format).*/ parse arg N hp . /*obtain optional arguments from the CL*/ if N=='' | N=="," then N= 19 /* " " " " " " */ if hp=='' | hp=="," then hip= 1000000 ...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#AWK
AWK
  # syntax: GAWK -f CIRCLES_OF_GIVEN_RADIUS_THROUGH_TWO_POINTS.AWK # converted from PL/I BEGIN { split("0.1234,0,0.1234,0.1234,0.1234",m1x,",") split("0.9876,2,0.9876,0.9876,0.9876",m1y,",") split("0.8765,0,0.1234,0.8765,0.1234",m2x,",") split("0.2345,0,0.9876,0.2345,0.9876",m2y,",") leng = split("2...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#AppleScript
AppleScript
on run   -- TRADITIONAL STRINGS ---------------------------------------------------   -- ts :: Array Int (String, String) -- 天干 tiangan – 10 heavenly stems set ts to zip(chars("甲乙丙丁戊己庚辛壬癸"), ¬ |words|("jiă yĭ bĭng dīng wù jĭ gēng xīn rén gŭi"))   -- ds :: Array Int (String, String) ...
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#6502_Assembly
6502 Assembly
LDA $D011  ;screen control register 1 AND #%00100000  ;bit 5 clear = text mode, bit 5 set = gfx mode BEQ isTerminal
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#Ada
Ada
with Ada.Text_IO; use Ada.Text_IO; with Interfaces.C_Streams; use Interfaces.C_Streams;   procedure Test_tty is begin if Isatty(Fileno(Stdout)) = 0 then Put_Line(Standard_Error, "stdout is not a tty."); else Put_Line(Standard_Error, "stdout is a tty."); end if; end Test_tty;
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#BBC_BASIC
BBC BASIC
DIM m1(2,2) m1() = 25, 15, -5, \ \ 15, 18, 0, \ \ -5, 0, 11 PROCcholesky(m1()) PROCprint(m1()) PRINT   @% = &2050A DIM m2(3,3) m2() = 18, 22, 54, 42, \ \ 22, 70, 86, 62, \ \ 54, 86, 174, 134, \ \ 42, 62, 134, 10...
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#C
C
#include <stdio.h> #include <stdlib.h> #include <math.h>   double *cholesky(double *A, int n) { double *L = (double*)calloc(n * n, sizeof(double)); if (L == NULL) exit(EXIT_FAILURE);   for (int i = 0; i < n; i++) for (int j = 0; j < (i+1); j++) { double s = 0; for (in...
http://rosettacode.org/wiki/Cheryl%27s_birthday
Cheryl's birthday
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is. Cheryl gave them a list of ten possible dates: May 15, May 16, May 19 June 17, June 18 July 14, July 16 August 14, August 15, August 17 Cheryl then tells Albert the   month   of birth, ...
#Ada
Ada
with Ada.Text_IO; use Ada.Text_IO;   procedure Main is type Months is (January, February, March, April, May, June, July, August, September, November, December); type day_num is range 1 .. 31; type birthdate is record Month  : Months; Day  : day_num; Active : Boolean; end recor...
http://rosettacode.org/wiki/Checkpoint_synchronization
Checkpoint synchronization
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st...
#BBC_BASIC
BBC BASIC
INSTALL @lib$+"TIMERLIB" nWorkers% = 3 DIM tID%(nWorkers%)   tID%(1) = FN_ontimer(10, PROCworker1, 1) tID%(2) = FN_ontimer(11, PROCworker2, 1) tID%(3) = FN_ontimer(12, PROCworker3, 1)   DEF PROCworker1 : PROCtask(1) : ENDPROC DEF PROCworker2 : PROCtask(2) : ENDPROC ...
http://rosettacode.org/wiki/Checkpoint_synchronization
Checkpoint synchronization
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st...
#C
C
#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <omp.h>   int main() { int jobs = 41, tid; omp_set_num_threads(5);   #pragma omp parallel shared(jobs) private(tid) { tid = omp_get_thread_num(); while (jobs > 0) { ...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#Elena
Elena
  // Weak array var stringArr := Array.allocate(5); stringArr[0] := "string";   // initialized array var intArray := new int[]{1, 2, 3, 4, 5};  
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#Kotlin
Kotlin
class Combinations(val m: Int, val n: Int) { private val combination = IntArray(m)   init { generate(0) }   private fun generate(k: Int) { if (k >= m) { for (i in 0 until m) print("${combination[i]} ") println() } else { for (j in 0 unt...
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#Prolog
Prolog
go :- write('Hello, World!'), nl.
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Zoea
Zoea
  program comments # this program does nothing   # zoea supports single line comments starting with a '#' char   /* zoea also supports multi line comments */  
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#Zoea_Visual
Zoea Visual
  (* this is a comment *) (* and this is a multiline comment (* with a nested comment *) *)  
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#zonnon
zonnon
  (* this is a comment *) (* and this is a multiline comment (* with a nested comment *) *)  
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#Arturo
Arturo
mulInv: function [a0, b0][ [a b x0]: @[a0 b0 0] result: 1 if b = 1 -> return result while [a > 1][ q: a / b a: a % b tmp: a a: b b: tmp result: result - q * x0 tmp: x0 x0: result result: tmp ] if result < 0 -> result: result...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Julia
Julia
using Primes   function trial_pretest(k::UInt64)   if ((k % 3)==0 || (k % 5)==0 || (k % 7)==0 || (k % 11)==0 || (k % 13)==0 || (k % 17)==0 || (k % 19)==0 || (k % 23)==0) return (k <= 23) end   return true end   function gcd_pretest(k::UInt64)   if (k <= 107) return true en...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
ClearAll[PrimeFactorCounts, U] PrimeFactorCounts[n_Integer] := Total[FactorInteger[n][[All, 2]]] U[n_, m_] := (6 m + 1) (12 m + 1) Product[2^i 9 m + 1, {i, 1, n - 2}] FindFirstChernickCarmichaelNumber[n_Integer?Positive] := Module[{step, i, m, formula, value}, step = Ceiling[2^(n - 4)]; If[n > 5, step *= 5]; i ...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Nim
Nim
import strutils, sequtils import bignum   const Max = 10 Factors: array[3..Max, int] = [1, 1, 2, 4, 8, 16, 32, 64] # 1 for n=3 then 2^(n-4). FirstPrimes = [3, 5, 7, 11, 13, 17, 19, 23]   #---------------------------------------------------------------------------------------------------   iterator factors(n, m:...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#CLU
CLU
% Chowla's function chowla = proc (n: int) returns (int) sum: int := 0 i: int := 2 while i*i <= n do if n//i = 0 then sum := sum + i j: int := n/i if i ~= j then sum := sum + j end end i := i + 1 end return(sum) ...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#Cowgol
Cowgol
include "cowgol.coh";   sub chowla(n: uint32): (sum: uint32) is sum := 0; var i: uint32 := 2;   while i*i <= n loop if n % i == 0 then sum := sum + i; var j := n / i; if i != j then sum := sum + j; end if; end if; i := i...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#JavaScript
JavaScript
(() => { 'use strict';   // ----------------- CHURCH NUMERALS -----------------   const churchZero = f => identity;     const churchSucc = n => f => compose(f)(n(f));     const churchAdd = m => n => f => compose(n(f))(m(f));     const churchMult = m => n => f => n...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#DM
DM
s
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#Dragon
Dragon
class run{ func val(){ showln 10+20 } }  
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#Raku
Raku
my @line-segments = (0, 0, 0, 100), (0, 0, 35, 0), (0, 35, 35, 35), (0, 0, 35, 35), (0, 35, 35, 0), ( 35, 0, 35, 35), (0, 0,-35, 0), (0, 35,-35, 35), (0, 0,-35, 35), (0, 35,-35, 0), (-35, 0,-35, 35), (0,100, 35,100), (0, 65, 35, 65), (0,100, 35, 65), (0, 65, 35,100), ( 35, 65, 35,100), (0,100,...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. 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 Provide a function to find the closest two p...
#Go
Go
package main   import ( "fmt" "math" "math/rand" "time" )   type xy struct { x, y float64 }   const n = 1000 const scale = 100.   func d(p1, p2 xy) float64 { return math.Hypot(p2.x-p1.x, p2.y-p1.y) }   func main() { rand.Seed(time.Now().Unix()) points := make([]xy, n) for i := range ...
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
Function[i, i^2 &] /@ Range@10 ->{1^2 &, 2^2 &, 3^2 &, 4^2 &, 5^2 &, 6^2 &, 7^2 &, 8^2 &, 9^2 &, 10^2 &}   %[[2]][] ->4
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Nemerle
Nemerle
using System.Console;   module Closures { Main() : void { def f(x) { fun() { x ** 2 } } def funcs = $[f(x) | x in $[0 .. 10]].ToArray(); // using array for easy indexing   WriteLine($"$(funcs[4]())"); WriteLine($"$(funcs[2]())"); } }
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Ring
Ring
  see "working..." + nl see "First 19 circular numbers are:" + nl n = 0 row = 0 Primes = []   while row < 19 n++ flag = 1 nStr = string(n) lenStr = len(nStr) for m = 1 to lenStr leftStr = left(nStr,m) rightStr = right(nStr,lenStr-m) strOk = rightStr + leftSt...
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Ruby
Ruby
require 'gmp' require 'prime' candidate_primes = Enumerator.new do |y| DIGS = [1,3,7,9] [2,3,5,7].each{|n| y << n.to_s} (2..).each do |size| DIGS.repeated_permutation(size) do |perm| y << perm.join if (perm == min_rotation(perm)) && GMP::Z(perm.join).probab_prime? > 0 end end end   def min_rotatio...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#BASIC256
BASIC256
  function twoCircles(x1, y1, x2, y2, radio) if x1 = x2 and y1 = y2 then #Si los puntos coinciden if radio = 0 then #a no ser que radio=0 print "Los puntos son los mismos " return "" else print "Hay cualquier número de círculos a través de un solo punto ("; x1; ", "; y1; ") de radio "; int(radio) ...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#AutoHotkey
AutoHotkey
Chinese_zodiac(year){ Animal := StrSplit("Rat,Ox,Tiger,Rabbit,Dragon,Snake,Horse,Goat,Monkey,Rooster,Dog,Pig", ",") AnimalCh := StrSplit("鼠牛虎兔龍蛇馬羊猴鸡狗豬") AnimalName := StrSplit("shǔ,niú,hǔ,tù,lóng,shé,mǎ,yáng,hóu,jī,gǒu,zhū", ",") Element := StrSplit("Wood,Fire,Earth,Metal,Water", ",") ElementCh := StrSplit("木火土...
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#C
C
#include <unistd.h> // for isatty() #include <stdio.h> // for fileno()   int main() { puts(isatty(fileno(stdout)) ? "stdout is tty" : "stdout is not tty"); return 0; }
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#C.23
C#
using System;   namespace CheckTerminal { class Program { static void Main(string[] args) { Console.WriteLine("Stdout is tty: {0}", Console.IsOutputRedirected); } } }
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#C.2B.2B
C++
#if _WIN32 #include <io.h> #define ISATTY _isatty #define FILENO _fileno #else #include <unistd.h> #define ISATTY isatty #define FILENO fileno #endif   #include <iostream>   int main() { if (ISATTY(FILENO(stdout))) { std::cout << "stdout is a tty\n"; } else { std::cout << "stdout is not a tty\n"...
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#C.23
C#
using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace Cholesky { class Program { /// <summary> /// This is example is written in C#, and compiles with .NET Framework 4.0 /// </summary> /// <param name="args"></param> static void...
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#Ada
Ada
with Ada.Text_IO; use Ada.Text_IO; with Interfaces.C_Streams; use Interfaces.C_Streams;   procedure Test_tty is begin if Isatty(Fileno(Stdin)) = 0 then Put_Line(Standard_Error, "stdin is not a tty."); else Put_Line(Standard_Error, "stdin is a tty."); end if; end Test_tty;
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#BaCon
BaCon
terminal = isatty(0) PRINT terminal
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#C
C
#include <unistd.h> //for isatty() #include <stdio.h> //for fileno()   int main(void) { puts(isatty(fileno(stdin)) ? "stdin is tty" : "stdin is not tty"); return 0; }
http://rosettacode.org/wiki/Cheryl%27s_birthday
Cheryl's birthday
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is. Cheryl gave them a list of ten possible dates: May 15, May 16, May 19 June 17, June 18 July 14, July 16 August 14, August 15, August 17 Cheryl then tells Albert the   month   of birth, ...
#AppleScript
AppleScript
use AppleScript version "2.4" use framework "Foundation" use scripting additions   property M : 1 -- Month property D : 2 -- Day   on run -- The MONTH with only one remaining day -- among the DAYs with unique months, -- EXCLUDING months with unique days, -- in Cheryl's list:   showList(uniquePairing...
http://rosettacode.org/wiki/Checkpoint_synchronization
Checkpoint synchronization
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st...
#C.2B.2B
C++
#include <iostream> #include <chrono> #include <atomic> #include <mutex> #include <random> #include <thread>   std::mutex cout_lock;   class Latch { std::atomic<int> semafor; public: Latch(int limit) : semafor(limit) {}   void wait() { semafor.fetch_sub(1); while(semafor.load() > 0) ...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#Elixir
Elixir
empty_list = [] list = [1,2,3,4,5] length(list) #=> 5 [0 | list] #=> [0,1,2,3,4,5] hd(list) #=> 1 tl(list) #=> [2,3,4,5] Enum.at(list,3) #=> 4 list ++ [6,7] #=> [1,2,3,4,5,6,7] list -- [4,2] ...
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#Lobster
Lobster
import std   // combi is an itertor that solves the Combinations problem for iota arrays as stated   def combi(m, n, f): let c = map(n): _   while true: f(c) var i = n-1 c[i] = c[i] + 1 if c[i] > m - 1: while c[i] >= m - n + i: i -= 1 i...
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#PureBasic
PureBasic
If a = 0 Debug "a = 0"   ElseIf a > 0 Debug "a > 0"   Else Debug "a < 0"   EndIf
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#AWK
AWK
# Usage: GAWK -f CHINESE_REMAINDER_THEOREM.AWK BEGIN { len = split("3 5 7", n) len = split("2 3 2", a) printf("%d\n", chineseremainder(n, a, len)) } function chineseremainder(n, a, len, p, i, prod, sum) { prod = 1 sum = 0 for (i = 1; i <= len; i++) prod *= n[i] for (i = 1; i <= le...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#PARI.2FGP
PARI/GP
  cherCar(n)={ my(C=vector(n));C[1]=6; C[2]=12; for(g=3,n,C[g]=2^(g-2)*9); my(i=1); my(N(g)=while(i<=n&ispseudoprime(g*C[i]+1),i=i+1); return(i>n)); i=1; my(G(g)=while(i<=n&isprime(g*C[i]+1),i=i+1); return(i>n)); i=1; if(n>4,i=2^(n-4)); if(n>5,i=i*5); my(m=i); while(!(N(m)&G(m)),m=m+i); printf("cherCar(%d...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#D
D
import std.stdio;   int chowla(int n) { int sum; for (int i = 2, j; i * i <= n; ++i) { if (n % i == 0) { sum += i + (i == (j = n / i) ? 0 : j); } } return sum; }   bool[] sieve(int limit) { // True denotes composite, false denotes prime. // Only interested in odd numb...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#jq
jq
def church(f; $x; $m): if $m == 0 then . elif $m == 1 then $x|f else church(f; $x; $m - 1) end;
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Julia
Julia
  id(x) = x -> x zero() = x -> id(x) add(m) = n -> (f -> (x -> n(f)(m(f)(x)))) mult(m) = n -> (f -> (x -> n(m(f))(x))) exp(m) = n -> n(m) succ(i::Int) = i + 1 succ(cn) = f -> (x -> f(cn(f)(x))) church2int(cn) = cn(succ)(0) int2church(n) = n < 0 ? throw("negative Church numeral") : (n == 0 ? zero() : succ(int2church(n -...
http://rosettacode.org/wiki/Classes
Classes
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T. The first type T from the class T sometimes is called the root type of the class. A class of types itself, a...
#DWScript
DWScript
type TMyClass = class private FSomeField: Integer; // by convention, fields are usually private and exposed as properties public constructor Create; begin FSomeField := -1; end; procedure SomeMethod; property SomeField: Integer read FSomeField write FSomeField; end;   procedure TM...
http://rosettacode.org/wiki/Cistercian_numerals
Cistercian numerals
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999. How they work All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp...
#REXX
REXX
/*REXX program displays a (non-negative 4-digit) integer in Cistercian (monk) numerals.*/ parse arg m /*obtain optional arguments from the CL*/ if m='' | m="," then m= 0 1 20 300 4000 5555 6789 9393 /*Not specified? Use defaults.*/ $.=; nnn= words(m) ...
http://rosettacode.org/wiki/Closest-pair_problem
Closest-pair problem
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Provide a function to find the closest two p...
#Groovy
Groovy
class Point { final Number x, y Point(Number x = 0, Number y = 0) { this.x = x; this.y = y } Number distance(Point that) { ((this.x - that.x)**2 + (this.y - that.y)**2)**0.5 } String toString() { "{x:${x}, y:${y}}" } }
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Nim
Nim
var funcs: seq[proc(): int] = @[]   for i in 0..9: (proc = let x = i funcs.add(proc (): int = x * x))()   for i in 0..8: echo "func[", i, "]: ", funcs[i]()
http://rosettacode.org/wiki/Closures/Value_capture
Closures/Value capture
Task Create a list of ten functions, in the simplest manner possible   (anonymous functions are encouraged),   such that the function at index   i   (you may choose to start   i   from either   0   or   1),   when run, should return the square of the index,   that is,   i 2. Display the result of runnin...
#Objeck
Objeck
use Collection.Generic;   class Capture { function : Main(args : String[]) ~ Nil { funcs := Vector->New()<FuncHolder<IntHolder> >;   for(i := 0; i < 10; i += 1;) { funcs->AddBack(FuncHolder->New(\() ~ IntHolder : () => i * i)<IntHolder>); };   each(i : funcs) { func := funcs->Get(i)-...
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Rust
Rust
// [dependencies] // rug = "1.8"   fn is_prime(n: u32) -> bool { if n < 2 { return false; } if n % 2 == 0 { return n == 2; } if n % 3 == 0 { return n == 3; } let mut p = 5; while p * p <= n { if n % p == 0 { return false; } p +=...
http://rosettacode.org/wiki/Circular_primes
Circular primes
Definitions A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime. For example: 1193 is a circular prime, since 1931, 9311 and 3119 are all also prime. Note that a number which is a cyclic permutation ...
#Scala
Scala
object CircularPrimes { def main(args: Array[String]): Unit = { println("First 19 circular primes:") var p = 2 var count = 0 while (count < 19) { if (isCircularPrime(p)) { if (count > 0) { print(", ") } print(p) count += 1 } p += 1 } ...
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points
Circles of given radius through two points
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points. Exceptions r==0.0 should be treated as never describing circles (except in the case where the points are coincident). If the points are coincident then an infinite number of circles with the point on thei...
#C
C
#include<stdio.h> #include<math.h>   typedef struct{ double x,y; }point;   double distance(point p1,point p2) { return sqrt((p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y)); }   void findCircles(point p1,point p2,double radius) { double separation = distance(p1,p2),mirrorDistance;   if(separation == 0.0) { radi...
http://rosettacode.org/wiki/Chinese_zodiac
Chinese zodiac
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo...
#AWK
AWK
  # syntax: GAWK -f CHINESE_ZODIAC.AWK BEGIN { print("year element animal aspect") split("Rat,Ox,Tiger,Rabbit,Dragon,Snake,Horse,Goat,Monkey,Rooster,Dog,Pig",animal_arr,",") split("Wood,Fire,Earth,Metal,Water",element_arr,",") n = split("1935,1938,1968,1972,1976,1984,1985,2017",year_arr,",") for (i...
http://rosettacode.org/wiki/Check_that_file_exists
Check that file exists
Task Verify that a file called     input.txt     and   a directory called     docs     exist. This should be done twice:     once for the current working directory,   and   once for a file and a directory in the filesystem root. Optional criteria (May 2015):   verify it works with:   zero-length files   an ...
#11l
11l
fs:is_file(‘input.txt’) fs:is_file(‘/input.txt’) fs:is_dir(‘docs’) fs:is_dir(‘/docs’)
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#COBOL
COBOL
*> *> istty, check id fd 0 is a tty *> Tectonics: cobc -xj istty.cob *> echo "test" | ./istty *> identification division. program-id. istty.   data division. working-storage section. 01 rc usage binary-long.   procedure division. ...
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#Common_Lisp
Common Lisp
(with-open-stream (s *standard-output*) (format T "stdout is~:[ not~;~] a terminal~%" (interactive-stream-p s)))
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#Crystal
Crystal
File.new("testfile").tty? #=> false File.new("/dev/tty").tty? #=> true STDOUT.tty? #=> true
http://rosettacode.org/wiki/Check_output_device_is_a_terminal
Check output device is a terminal
Task Demonstrate how to check whether the output device is a terminal or not. Related task   Check input device is a terminal
#D
D
import std.stdio;   extern(C) int isatty(int);   void main() { writeln("Stdout is tty: ", stdout.fileno.isatty == 1); }
http://rosettacode.org/wiki/Cholesky_decomposition
Cholesky decomposition
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose: A = L L T {\displaystyle A=LL^{T}} L {\displaystyle L} is called the Cholesky factor of A {\displaystyle A} , and can be interpreted as a generalized square r...
#C.2B.2B
C++
#include <cassert> #include <cmath> #include <iomanip> #include <iostream> #include <vector>   template <typename scalar_type> class matrix { public: matrix(size_t rows, size_t columns) : rows_(rows), columns_(columns), elements_(rows * columns) {}   matrix(size_t rows, size_t columns, scalar_type value...
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#COBOL
COBOL
*> *> istty, check id fd 0 is a tty *> Tectonics: cobc -xj istty.cob *> echo "test" | ./istty *> identification division. program-id. istty.   data division. working-storage section. 01 rc usage binary-long.   procedure division. ...
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#Common_Lisp
Common Lisp
(with-open-stream (s *standard-input*) (format T "stdin is~:[ not~;~] a terminal~%" (interactive-stream-p s)))
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#Crystal
Crystal
File.new("testfile").tty? #=> false File.new("/dev/tty").tty? #=> true STDIN.tty? #=> true
http://rosettacode.org/wiki/Check_input_device_is_a_terminal
Check input device is a terminal
Task Demonstrate how to check whether the input device is a terminal or not. Related task   Check output device is a terminal
#D
D
import std.stdio;   extern(C) int isatty(int);   void main() { if (isatty(0)) writeln("Input comes from tty."); else writeln("Input doesn't come from tty."); }
http://rosettacode.org/wiki/Cheryl%27s_birthday
Cheryl's birthday
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is. Cheryl gave them a list of ten possible dates: May 15, May 16, May 19 June 17, June 18 July 14, July 16 August 14, August 15, August 17 Cheryl then tells Albert the   month   of birth, ...
#Arturo
Arturo
dates: [ [May 15] [May 16] [May 19] [June 17] [June 18] [July 14] [July 16] [August 14] [August 15] [August 17] ]   print ["possible dates:" dates]   print "\n(1) Albert: I don't know when Cheryl's birthday is, but I know that Bernard does not know too." print "\t-> meaning: the month cannot have a uniq...
http://rosettacode.org/wiki/Checkpoint_synchronization
Checkpoint synchronization
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st...
#Clojure
Clojure
(ns checkpoint.core (:gen-class) (:require [clojure.core.async :as async :refer [go <! >! <!! >!! alts! close!]] [clojure.string :as string]))   (defn coordinate [ctl-ch resp-ch combine] (go (<! (async/timeout 2000)) ;delay a bit to allow worker setup (loop [members {}, received {}] ;maps by i...
http://rosettacode.org/wiki/Collections
Collections
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Collections are abstractions to represent sets of values. In statically-typed languages, the values are typically of a common data type. Task Create a collection, and add a fe...
#Factor
Factor
USING: assocs deques dlists lists lists.lazy sequences sets ;   ! ===fixed-size sequences=== { 1 2 "foo" 3 } ! array [ 1 2 3 + * ]  ! quotation "Hello, world!" ! string B{ 1 2 3 }  ! byte array ?{ f t t }  ! bit array   ! Add an element to a fixed-size sequence { 1 2 3 } 4 suffix ! { 1 2 3 4 }   ! Append a seq...
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#Logo
Logo
to comb :n :list if :n = 0 [output [[]]] if empty? :list [output []] output sentence map [sentence first :list ?] comb :n-1 bf :list ~ comb :n bf :list end print comb 3 [0 1 2 3 4]
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#Python
Python
if x == 0: foo() elif x == 1: bar() elif x == 2: baz() else: boz()
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#Bracmat
Bracmat
( ( mul-inv = a b b0 q x0 x1 .  !arg:(?a.?b:?b0) & ( !b:1 | 0:?x0 & 1:?x1 & whl ' ( !a:>1 & (!b.mod$(!a.!b):?q.!x1+-1*!q*!x0.!x0)  : (?a.?b.?x0.?x1) ) & ( !x1:<0&!b0+!x1 | !x1 ) ...
http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#C
C
#include <stdio.h>   // returns x where (a * x) % b == 1 int mul_inv(int a, int b) { int b0 = b, t, q; int x0 = 0, x1 = 1; if (b == 1) return 1; while (a > 1) { q = a / b; t = b, b = a % b, a = t; t = x0, x0 = x1 - q * x0, x1 = t; } if (x1 < 0) x1 += b0; return x1; }   int chinese_remainder(int *n, int *a,...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Perl
Perl
use 5.020; use warnings; use ntheory qw/:all/; use experimental qw/signatures/;   sub chernick_carmichael_factors ($n, $m) { (6*$m + 1, 12*$m + 1, (map { (1 << $_) * 9*$m + 1 } 1 .. $n-2)); }   sub chernick_carmichael_number ($n, $callback) {   my $multiplier = ($n > 4) ? (1 << ($n-4)) : 1;   for (my $m = 1...
http://rosettacode.org/wiki/Chernick%27s_Carmichael_numbers
Chernick's Carmichael numbers
In 1939, Jack Chernick proved that, for n ≥ 3 and m ≥ 1: U(n, m) = (6m + 1) * (12m + 1) * Product_{i=1..n-2} (2^i * 9m + 1) is a Carmichael number if all the factors are primes and, for n > 4, m is a multiple of 2^(n-4). Example U(3, m) = (6m + 1) * (12m + 1) * (18m + 1) U(4, m) = U(3, m) * (2^2 * 9m + 1)...
#Phix
Phix
with javascript_semantics function chernick_carmichael_factors(integer n, m) sequence res = {6*m + 1, 12*m + 1} for i=1 to n-2 do res &= power(2,i) * 9*m + 1 end for return res end function include mpfr.e mpz p = mpz_init() function m_prime(atom a) mpz_set_d(p,a) return mpz_prime(p) ...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#Delphi
Delphi
func chowla(n) { var sum = 0 var i = 2 var j = 0 while i * i <= n { if n % i == 0 { j = n / i var app = if i == j { 0 } else { j } sum += i + app } i += 1 } return sum }   func sie...
http://rosettacode.org/wiki/Chowla_numbers
Chowla numbers
Chowla numbers are also known as:   Chowla's function   chowla numbers   the chowla function   the chowla number   the chowla sequence The chowla number of   n   is   (as defined by Chowla's function):   the sum of the divisors of   n     excluding unity and   n   where   n   is a positive integer The s...
#Dyalect
Dyalect
func chowla(n) { var sum = 0 var i = 2 var j = 0 while i * i <= n { if n % i == 0 { j = n / i var app = if i == j { 0 } else { j } sum += i + app } i += 1 } return sum }   func sie...
http://rosettacode.org/wiki/Church_numerals
Church numerals
Task In the Church encoding of natural numbers, the number N is encoded by a function that applies its first argument N times to its second argument. Church zero always returns the identity function, regardless of its first argument. In other words, the first argument is not applied to the second argument at all. C...
#Lambdatalk
Lambdatalk
  {def succ {lambda {:n :f :x} {:f {:n :f :x}}}} {def add {lambda {:n :m :f :x} {{:n :f} {:m :f :x}}}} {def mul {lambda {:n :m :f} {:m {:n :f}}}} {def power {lambda {:n :m} {:m :n}}}   {def church {lambda {:n} {{:n {+ {lambda {:x} {+ :x 1}}}} 0}}}   {def zero {lambda {:f :x} :x}} {def three {succ {succ {succ zero}}}}...