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http://rosettacode.org/wiki/Short-circuit_evaluation
Short-circuit evaluation
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Assume functions   a   and   b   return boolean values,   and further, the execution of function   b   takes considerable resources without side effects, an...
#Liberty_BASIC
Liberty BASIC
print "AND" for i = 0 to 1 for j = 0 to 1 print "a("; i; ") AND b( "; j; ")" res =a( i) 'call always if res <>0 then 'short circuit if 0 res = b( j) end if print "=>",res next next   print "---------------------------------" print "OR" for i = 0 to 1 f...
Give a code snippet in #Liberty_BASIC Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Assume functions   a   and   b   return boolean values,   and further, the execution of function   b   takes consider...
christopher/rosetta-code
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#PARI.2FGP
PARI/GP
f(a[..])=for(i=1,#a,print(a[i]))
Give a code snippet in #PARI.2FGP Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. ...
christopher/rosetta-code
http://rosettacode.org/wiki/Percolation/Site_percolation
Percolation/Site percolation
Percolation Simulation This is a simulation of aspects of mathematical percolation theory. For other percolation simulations, see Category:Percolation Simulations, or: 1D finite grid simulation Mean run density 2D finite grid simulations Site percolation | Bond percolation | Mean cluster density Given an M × N...
#Go
Go
package main   import ( "bytes" "fmt" "math/rand" "time" )   func main() { const ( m, n = 15, 15 t = 1e4 minp, maxp, Δp = 0, 1, 0.1 )   rand.Seed(2) // Fixed seed for repeatable example grid g := NewGrid(.5, m, n) g.Percolate() fmt.Println(g)   rand.Seed(time.Now().UnixNano()) //...
Give a code snippet in #Go Percolation Simulation This is a simulation of aspects of mathematical percolation theory. For other percolation simulations, see Category:Percolation Simulations, or: 1D finite grid simulation Mean run density 2D finite grid simulations Site percolation | Bond percolation | Mean cluster...
christopher/rosetta-code
http://rosettacode.org/wiki/Last_Friday_of_each_month
Last Friday of each month
Task Write a program or a script that returns the date of the last Fridays of each month of a given year. The year may be given through any simple input method in your language (command line, std in, etc). Example of an expected output: ./last_fridays 2012 2012-01-27 2012-02-24 2012-03-30 2012-04-27 2012-05-25 20...
#K
K
  / List the dates of last Fridays of each month of / a given year / lastfridt.k   isleap: {(+/~x!' 4 100 400)!2} wd: {(_jd x)!7} dom: (31;28;31;30;31;30;31;31;30;31;30;31) init: {:[isleap x;dom[1]::29;dom[1]::28]} wdme: {[m;y]; init y; dt:(10000*y)+(100*m)+dom[m-1];jd::(_jd dt);mewd::(wd dt)} lfd: {[m;y]; wdme[m;y];:[...
Give a code snippet in #K Task Write a program or a script that returns the date of the last Fridays of each month of a given year. The year may be given through any simple input method in your language (command line, std in, etc). Example of an expected output: ./last_fridays 2012 2012-01-27 2012-02-24 2012-03-...
christopher/rosetta-code
http://rosettacode.org/wiki/Bernoulli_numbers
Bernoulli numbers
Bernoulli numbers are used in some series expansions of several functions   (trigonometric, hyperbolic, gamma, etc.),   and are extremely important in number theory and analysis. Note that there are two definitions of Bernoulli numbers;   this task will be using the modern usage   (as per   The National Institute of S...
#Haskell
Haskell
import Data.Ratio import System.Environment   main = getArgs >>= printM . defaultArg where defaultArg as = if null as then 60 else read (head as)   printM m = mapM_ (putStrLn . printP) . takeWhile ((<= m) . fst) . filter (\(_, b) -> b /= 0 % 1) . zip [0 ..] $ bernoullis   printP (i, r)...
Give a code snippet in #Haskell Bernoulli numbers are used in some series expansions of several functions   (trigonometric, hyperbolic, gamma, etc.),   and are extremely important in number theory and analysis. Note that there are two definitions of Bernoulli numbers;   this task will be using the modern usage   (as ...
christopher/rosetta-code
http://rosettacode.org/wiki/Benford%27s_law
Benford's law
This page uses content from Wikipedia. The original article was at Benford's_law. 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) Benford's law, also called the first-digit law, refers to the freque...
#Delphi
Delphi
defmodule Benfords_law do def distribution(n), do: :math.log10( 1 + (1 / n) )   def task(total \\ 1000) do IO.puts "Digit Actual Benfords expected" fib(total) |> Enum.group_by(fn i -> hd(to_char_list(i)) end) |> Enum.map(fn {key,list} -> {key - ?0, length(list)} end) |> Enum.sort |> Enum.eac...
Give a code snippet in #Delphi This page uses content from Wikipedia. The original article was at Benford's_law. 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) Benford's law, also called the first...
christopher/rosetta-code
http://rosettacode.org/wiki/Stair-climbing_puzzle
Stair-climbing puzzle
From Chung-Chieh Shan (LtU): Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function detects what happens and returns a...
#PicoLisp
PicoLisp
(de stepUp () (until (step1) # ('step1', because 'step' is a system function) (stepUp) ) )
Give a code snippet in #PicoLisp From Chung-Chieh Shan (LtU): Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function ...
christopher/rosetta-code
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers
Luhn test of credit card numbers
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of the digits in the number. Tak...
#Bracmat
Bracmat
( luhn = sum odd even . 0:?sum & rev$!arg:?arg & whl ' ( @( !arg  :  %?odd ( %?even ?arg | :?arg&0:?even ) ) & !odd+mod$(2*!even.10)+div$(!even.5)+!sum:?sum ) & mod$(!sum.10):0 ) & ...
Give a code snippet in #Bracmat The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order ...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_multiples_of_3_and_5
Sum multiples of 3 and 5
Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
#Arturo
Arturo
sumMul35: function [n][ sum select 1..n-1 [x][or? 0=x%3 0=x%5] ]   print sumMul35 1000
Give a code snippet in #Arturo Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/With_multiple_ranges
Loops/With multiple ranges
Loops/With multiple ranges You are encouraged to solve this task according to the task description, using any language you may know. Some languages allow multiple loop ranges, such as the PL/I example (snippet) below. /* all variables are DECLARED as integers. */ prod=...
#C.2B.2B
C++
#include <iostream> #include <cmath> #include <vector>   using std::abs; using std::cout; using std::pow; using std::vector;     int main() { int prod = 1, sum = 0, x = 5, y = -5, z = -2, one = 1, three = 3, seven = 7;   auto summingValues...
Give a code snippet in #C.2B.2B Loops/With multiple ranges You are encouraged to solve this task according to the task description, using any language you may know. Some languages allow multiple loop ranges, such as the PL/I example (snippet) below. /* all variables are DECLARE...
christopher/rosetta-code
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#BCPL
BCPL
get "libhdr"   let corput(n, base, num, denom) be $( let p = 0 and q = 1 until n=0 $( p := p * base + n rem base q := q * base n := n / base $)    !num := p  !denom := q   until p=0 $( n := p p := q rem p q := n $)    !num := !num / q  !denom := !de...
Give a code snippet in #BCPL When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\d...
christopher/rosetta-code
http://rosettacode.org/wiki/Repeat_a_string
Repeat a string
Take a string and repeat it some number of times. Example: repeat("ha", 5)   =>   "hahahahaha" If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****"). Other tasks re...
#BASIC
BASIC
function StringRepeat$ (s$, n) cad$ = "" for i = 1 to n cad$ += s$ next i return cad$ end function   print StringRepeat$("rosetta", 1) print StringRepeat$("ha", 5) print StringRepeat$("*", 5) end
Give a code snippet in #BASIC Take a string and repeat it some number of times. Example: repeat("ha", 5)   =>   "hahahahaha" If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) ...
christopher/rosetta-code
http://rosettacode.org/wiki/Emirp_primes
Emirp primes
An   emirp   (prime spelled backwards)   are primes that when reversed   (in their decimal representation)   are a different prime. (This rules out palindromic primes.) Task   show the first   twenty   emirps   show all emirps between   7,700   and   8,000   show the   10,000th   emirp In each list, the numbe...
#Go
Go
package main   import ( "flag" "fmt" "github.com/jbarham/primegen.go" // Sieve of Atkin implementation "math" )   // primeCache is a simple cache of small prime numbers, it very // well might be faster to just regenerate them as needed. type primeCache struct { gen *primegen.Primegen primes []uint64 }   func N...
Give a code snippet in #Go An   emirp   (prime spelled backwards)   are primes that when reversed   (in their decimal representation)   are a different prime. (This rules out palindromic primes.) Task   show the first   twenty   emirps   show all emirps between   7,700   and   8,000   show the   10,000th   emi...
christopher/rosetta-code
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could ...
#Icon_and_Unicon
Icon and Unicon
procedure timef(f) #: time a function f local gcol,alloc,used,size,runtime,header,x,i   title := ["","total","static","string","block"] # headings collect() # start with collected memory (before baseline) every put(gcol := [], -&collections) ...
Give a code snippet in #Icon_and_Unicon Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system ti...
christopher/rosetta-code
http://rosettacode.org/wiki/Modular_exponentiation
Modular exponentiation
Find the last   40   decimal digits of   a b {\displaystyle a^{b}} ,   where   a = 2988348162058574136915891421498819466320163312926952423791023078876139 {\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139}   b = 235139930337346448646612254452369009474497523...
#FreeBASIC
FreeBASIC
    'From first principles (No external library) Function _divide(n1 As String,n2 As String,decimal_places As Integer=10,dpflag As String="s") As String Dim As String number=n1,divisor=n2 dpflag=Lcase(dpflag) 'For MOD Dim As Integer modstop If dpflag="mod" Then If Len(n1)<Len(n2) Then Retur...
Give a code snippet in #FreeBASIC Find the last   40   decimal digits of   a b {\displaystyle a^{b}} ,   where   a = 2988348162058574136915891421498819466320163312926952423791023078876139 {\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139}   b = 2351399303...
christopher/rosetta-code
http://rosettacode.org/wiki/Assertions
Assertions
Assertions are a way of breaking out of code when there is an error or an unexpected input. Some languages throw exceptions and some treat it as a break point. Task Show an assertion in your language by asserting that an integer variable is equal to 42.
#Dyalect
Dyalect
var x = 42 assert(42, x)
Give a code snippet in #Dyalect Assertions are a way of breaking out of code when there is an error or an unexpected input. Some languages throw exceptions and some treat it as a break point. Task Show an assertion in your language by asserting that an integer variable is equal to 42.
christopher/rosetta-code
http://rosettacode.org/wiki/Associative_array/Creation
Associative array/Creation
Task The goal is to create an associative array (also known as a dictionary, map, or hash). Related tasks: Associative arrays/Iteration Hash from two arrays See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element ins...
#Aikido
Aikido
  var names = {} // empty map names["foo"] = "bar" names[3] = 4   // initialized map var names2 = {"foo": bar, 3:4}   // lookup map var name = names["foo"] if (typeof(name) == "none") { println ("not found") } else { println (name) }   // remove from map delete names["foo"]      
Give a code snippet in #Aikido Task The goal is to create an associative array (also known as a dictionary, map, or hash). Related tasks: Associative arrays/Iteration Hash from two arrays See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition,...
christopher/rosetta-code
http://rosettacode.org/wiki/Hash_from_two_arrays
Hash from two arrays
Task Using two Arrays of equal length, create a Hash object where the elements from one array (the keys) are linked to the elements of the other (the values) Related task   Associative arrays/Creation
#C.2B.2B
C++
#include <unordered_map> #include <string>   int main() { std::string keys[] = { "1", "2", "3" }; std::string vals[] = { "a", "b", "c" };   std::unordered_map<std::string, std::string> hash; for( int i = 0 ; i < 3 ; i++ ) hash[ keys[i] ] = vals[i] ; }
Give a code snippet in #C.2B.2B Task Using two Arrays of equal length, create a Hash object where the elements from one array (the keys) are linked to the elements of the other (the values) Related task   Associative arrays/Creation
christopher/rosetta-code
http://rosettacode.org/wiki/String_case
String case
Task Take the string     alphaBETA     and demonstrate how to convert it to:   upper-case     and   lower-case Use the default encoding of a string literal or plain ASCII if there is no string literal in your language. Note: In some languages alphabets toLower and toUpper is not reversable. Show any additional...
#Befunge
Befunge
"ATEBahpla" > : #v_ 25* , @ >48*-v > :: "`"` \"{"\` * | > , v > ^ ^ <
Give a code snippet in #Befunge Task Take the string     alphaBETA     and demonstrate how to convert it to:   upper-case     and   lower-case Use the default encoding of a string literal or plain ASCII if there is no string literal in your language. Note: In some languages alphabets toLower and toUpper is not...
christopher/rosetta-code
http://rosettacode.org/wiki/RIPEMD-160
RIPEMD-160
RIPEMD-160 is another hash function; it computes a 160-bit message digest. There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160. For padding the message, RIPEMD-160 acts like MD4 (RFC 1320). Find the RIPEMD-160 message digest of a string of octets. Use the ASCII encoded string “Rosetta Cod...
#Julia
Julia
using Nettle   labels = ["\"\" (empty string)", "\"a\"", "\"abc\"", "\"message digest\"", "\"a...z\"", "\"abcdbcde...nopq\"", "\"A...Za...z0...9\"", "8 times \"1234567890\"", "1 million times \"a\""] texts = ["", "a", "abc", "message digest", "abcdefghijklmnopqrstuvwxyz", "abcdbcdecdefde...
Give a code snippet in #Julia RIPEMD-160 is another hash function; it computes a 160-bit message digest. There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160. For padding the message, RIPEMD-160 acts like MD4 (RFC 1320). Find the RIPEMD-160 message digest of a string of octets. Use the AS...
christopher/rosetta-code
http://rosettacode.org/wiki/Draw_a_pixel
Draw a pixel
Task Create a window and draw a pixel in it, subject to the following:  the window is 320 x 240  the color of the pixel must be red (255,0,0)  the position of the pixel is x = 100, y = 100
#GB_BASIC
GB BASIC
10 color 1 20 point 100,100
Give a code snippet in #GB_BASIC Task Create a window and draw a pixel in it, subject to the following:  the window is 320 x 240  the color of the pixel must be red (255,0,0)  the position of the pixel is x = 100, y = 100
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/While
Loops/While
Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For...
#Java
Java
int i = 1024; while(i > 0){ System.out.println(i); i >>= 1; //also acceptable: i /= 2; }
Give a code snippet in #Java Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward...
christopher/rosetta-code
http://rosettacode.org/wiki/Display_a_linear_combination
Display a linear combination
Task Display a finite linear combination in an infinite vector basis ( e 1 , e 2 , … ) {\displaystyle (e_{1},e_{2},\ldots )} . Write a function that, when given a finite list of scalars ( α 1 , α 2 , … ) {\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )} , creates a string representing t...
#Racket
Racket
#lang racket/base (require racket/match racket/string)   (define (linear-combination->string es) (let inr ((es es) (i 1) (rv "")) (match* (es rv) [((list) "") "0"] [((list) rv) rv] [((list (? zero?) t ...) rv) (inr t (add1 i) rv)] [((list n t ...) rv) (define ±n (mat...
Give a code snippet in #Racket Task Display a finite linear combination in an infinite vector basis ( e 1 , e 2 , … ) {\displaystyle (e_{1},e_{2},\ldots )} . Write a function that, when given a finite list of scalars ( α 1 , α 2 , … ) {\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )} , ...
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/For_with_a_specified_step
Loops/For with a specified step
Task Demonstrate a   for-loop   where the step-value is greater than one. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops/Increment loop index within loop b...
#PARI.2FGP
PARI/GP
forstep(n=1,10,2,print(n))
Give a code snippet in #PARI.2FGP Task Demonstrate a   for-loop   where the step-value is greater than one. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For with a specified step   Loops/Foreach   Loops...
christopher/rosetta-code
http://rosettacode.org/wiki/Metered_concurrency
Metered concurrency
The goal of this task is to create a counting semaphore used to control the execution of a set of concurrent units. This task intends to demonstrate coordination of active concurrent units through the use of a passive concurrent unit. The operations for a counting semaphore are acquire, release, and count. Each active ...
#Oforth
Oforth
import: parallel   Object Class new: Semaphore(ch)   Semaphore method: initialize(n) Channel newSize(n) dup := ch #[ 1 over send drop ] times(n) drop ;   Semaphore method: acquire @ch receive drop ; Semaphore method: release 1 @ch send drop ;
Give a code snippet in #Oforth The goal of this task is to create a counting semaphore used to control the execution of a set of concurrent units. This task intends to demonstrate coordination of active concurrent units through the use of a passive concurrent unit. The operations for a counting semaphore are acquire, ...
christopher/rosetta-code
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#Quackery
Quackery
[ stack [ 0 0 0 0 0 0 0 ] ] is bins ( --> s )   [ 7 times [ 0 bins take i poke bins put ] ] is emptybins ( --> )   [ bins share over peek 1+ bins take rot poke bins put ] is bincrement ( n --> )   [ emptybins ove...
Give a code snippet in #Quackery This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing rand...
christopher/rosetta-code
http://rosettacode.org/wiki/Kronecker_product_based_fractals
Kronecker product based fractals
This task is based on   Kronecker product   of two matrices. If your language has no a built-in function for such product then you need to implement it first. The essence of fractals is self-replication (at least, self-similar replications). So, using   n   times self-product of the matrix   (filled with 0/1)   we ...
#zkl
zkl
var [const] GSL=Import.lib("zklGSL"); // libGSL (GNU Scientific Library) fcn kronecker(A,B){ //--> new Matrix m,n, p,q := A.rows,A.cols, B.rows,B.cols; r:=GSL.Matrix(m*p, n*q); foreach i,j,k,l in (m,n,p,q){ r[p*i + k, q*j + l]=A[i,j]*B[k,l] } r }   fcn kfractal(M,n,fname){ R:=M; do(n){ R=kronecker...
Give a code snippet in #zkl This task is based on   Kronecker product   of two matrices. If your language has no a built-in function for such product then you need to implement it first. The essence of fractals is self-replication (at least, self-similar replications). So, using   n   times self-product of the mat...
christopher/rosetta-code
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#Oz
Oz
fun{FibI N} Temp = {NewCell 0} A = {NewCell 0} B = {NewCell 1} in for I in 1..N do Temp := @A + @B A := @B B := @Temp end @A end
Give a code snippet in #Oz The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are ge...
christopher/rosetta-code
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#AppleScript
AppleScript
on isqrt(x) set q to 1 repeat until (q > x) set q to q * 4 end repeat set z to x set r to 0 repeat while (q > 1) set q to q div 4 set t to z - r - q set r to r div 2 if (t > -1) then set z to t set r to r + q end if end ...
Give a code snippet in #AppleScript Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your co...
christopher/rosetta-code
http://rosettacode.org/wiki/Knapsack_problem/Unbounded
Knapsack problem/Unbounded
A traveler gets diverted and has to make an unscheduled stop in what turns out to be Shangri La.   Opting to leave, he is allowed to take as much as he likes of the following items, so long as it will fit in his knapsack, and he can carry it. He knows that he can carry no more than   25   'weights' in total;   and tha...
#Modula-3
Modula-3
MODULE Knapsack EXPORTS Main;   FROM IO IMPORT Put; FROM Fmt IMPORT Int, Real;   TYPE Bounty = RECORD value: INTEGER; weight, volume: REAL; END;   VAR totalWeight, totalVolume: REAL; maxPanacea, maxIchor, maxGold, maxValue: INTEGER := 0; n: ARRAY [1..3] OF INTEGER; panacea, ichor, gold, sack, current: B...
Give a code snippet in #Modula-3 A traveler gets diverted and has to make an unscheduled stop in what turns out to be Shangri La.   Opting to leave, he is allowed to take as much as he likes of the following items, so long as it will fit in his knapsack, and he can carry it. He knows that he can carry no more than   ...
christopher/rosetta-code
http://rosettacode.org/wiki/Catalan_numbers
Catalan numbers
Catalan numbers You are encouraged to solve this task according to the task description, using any language you may know. Catalan numbers are a sequence of numbers which can be defined directly: C n = 1 n + 1 ( 2 n n ) = ( 2 n ) ! ( n + 1 ) ! n !  for  n ≥ 0. {\displaystyle C...
#Vala
Vala
namespace CatalanNumbers { public class CatalanNumberGenerator { private static double factorial(double n) { if (n == 0) return 1; return n * factorial(n - 1); }   public double first_method(double n) { const double top_multiplier = 2; return factorial(top_multiplier * n) /...
Give a code snippet in #Vala Catalan numbers You are encouraged to solve this task according to the task description, using any language you may know. Catalan numbers are a sequence of numbers which can be defined directly: C n = 1 n + 1 ( 2 n n ) = ( 2 n ) ! ( n + 1 ) ! n !  f...
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Mode
Averages/Mode
Task[edit] Write a program to find the mode value of a collection. The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique. If it is not appropriate or possible to support a general collection, use a vector (array), if possible. If it is not appropriat...
#Octave
Octave
function m = mode2(v) sv = sort(v); % build two vectors, vals and c, so that % c(i) holds how many times vals(i) appears i = 1; c = []; vals = []; while (i <= numel(v) ) tc = sum(sv==sv(i)); % it would be faster to count % them "by hand", since sv is sorted... c = [c, tc]; ...
Give a code snippet in #Octave Task[edit] Write a program to find the mode value of a collection. The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique. If it is not appropriate or possible to support a general collection, use a vector (array), if p...
christopher/rosetta-code
http://rosettacode.org/wiki/User_input/Text
User input/Text
User input/Text is part of Short Circuit's Console Program Basics selection. Task Input a string and the integer   75000   from the text console. See also: User input/Graphical
#PicoLisp
PicoLisp
(in NIL # Guarantee reading from standard input (let (Str (read) Num (read)) (prinl "The string is: \"" Str "\"") (prinl "The number is: " Num) ) )
Give a code snippet in #PicoLisp User input/Text is part of Short Circuit's Console Program Basics selection. Task Input a string and the integer   75000   from the text console. See also: User input/Graphical
christopher/rosetta-code
http://rosettacode.org/wiki/Associative_array/Creation
Associative array/Creation
Task The goal is to create an associative array (also known as a dictionary, map, or hash). Related tasks: Associative arrays/Iteration Hash from two arrays See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element ins...
#APL
APL
⍝ Create a namespace ("hash") X←⎕NS ⍬   ⍝ Assign some names X.this←'that' X.foo←88   ⍝ Access the names X.this that   ⍝ Or do it the array way X.(foo this) 88 that   ⍝ Namespaces are first class objects sales ← ⎕NS ⍬ sales.(prices quantities) ← (10...
Give a code snippet in #APL Task The goal is to create an associative array (also known as a dictionary, map, or hash). Related tasks: Associative arrays/Iteration Hash from two arrays See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, El...
christopher/rosetta-code
http://rosettacode.org/wiki/Safe_addition
Safe addition
Implementation of   interval arithmetic   and more generally fuzzy number arithmetic require operations that yield safe upper and lower bounds of the exact result. For example, for an addition, it is the operations   +↑   and   +↓   defined as:   a +↓ b ≤ a + b ≤ a +↑ b. Additionally it is desired that the widt...
#Nim
Nim
import fenv, strutils   proc `++`(a, b: float): tuple[lower, upper: float] = let a {.volatile.} = a b {.volatile.} = b orig = fegetround() discard fesetround FE_DOWNWARD result.lower = a + b discard fesetround FE_UPWARD result.upper = a + b discard fesetround orig   proc ff(a: float): string = a...
Give a code snippet in #Nim Implementation of   interval arithmetic   and more generally fuzzy number arithmetic require operations that yield safe upper and lower bounds of the exact result. For example, for an addition, it is the operations   +↑   and   +↓   defined as:   a +↓ b ≤ a + b ≤ a +↑ b. Additionall...
christopher/rosetta-code
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#FreeBASIC
FreeBASIC
' person.bi file Type Person name As String age As UInteger Declare Operator Cast() As String End Type   Operator Person.Cast() As String Return "[" + This.name + ", " + Str(This.age) + "]" End Operator
Give a code snippet in #FreeBASIC Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
christopher/rosetta-code
http://rosettacode.org/wiki/Find_the_missing_permutation
Find the missing permutation
ABCD CABD ACDB DACB BCDA ACBD ADCB CDAB DABC BCAD CADB CDBA ...
#Java
Java
import java.util.ArrayList;   import com.google.common.base.Joiner; import com.google.common.collect.ImmutableSet; import com.google.common.collect.Lists;   public class FindMissingPermutation { public static void main(String[] args) { Joiner joiner = Joiner.on("").skipNulls(); ImmutableSet<String> s = ImmutableSe...
Give a code snippet in #Java ABCD CABD ACDB DACB BCDA ACBD ADCB CDAB DABC BCAD CADB ...
christopher/rosetta-code
http://rosettacode.org/wiki/Function_definition
Function definition
A function is a body of code that returns a value. The value returned may depend on arguments provided to the function. Task Write a definition of a function called "multiply" that takes two arguments and returns their product. (Argument types should be chosen so as not to distract from showing how functions are ...
#VBScript
VBScript
function multiply( multiplicand, multiplier ) multiply = multiplicand * multiplier end function
Give a code snippet in #VBScript A function is a body of code that returns a value. The value returned may depend on arguments provided to the function. Task Write a definition of a function called "multiply" that takes two arguments and returns their product. (Argument types should be chosen so as not to distra...
christopher/rosetta-code
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. 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) In algebra, polynomial long division is an algorithm for d...
#Smalltalk
Smalltalk
Object subclass: Polynomial [ |coeffs| Polynomial class >> new [ ^ super basicNew init ] init [ coeffs := OrderedCollection new. ^ self ] Polynomial class >> newWithCoefficients: coefficients [ |r| r := super basicNew. ^ r initWithCoefficients: coefficients ] initWithCoefficients: coefficients [...
Give a code snippet in #Smalltalk This page uses content from Wikipedia. The original article was at Polynomial long division. 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) In algebra, polynomial ...
christopher/rosetta-code
http://rosettacode.org/wiki/First-class_functions
First-class functions
A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming: Create new functions from preexisting functions at run-time Store functions in collections Use functions as arguments to other functions Use functions as retu...
#Python
Python
>>> # Some built in functions and their inverses >>> from math import sin, cos, acos, asin >>> # Add a user defined function and its inverse >>> cube = lambda x: x * x * x >>> croot = lambda x: x ** (1/3.0) >>> # First class functions allow run-time creation of functions from functions >>> # return function compose(f,g...
Give a code snippet in #Python A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming: Create new functions from preexisting functions at run-time Store functions in collections Use functions as arguments to other ...
christopher/rosetta-code
http://rosettacode.org/wiki/Comma_quibbling
Comma quibbling
Comma quibbling is a task originally set by Eric Lippert in his blog. Task Write a function to generate a string output which is the concatenation of input words from a list/sequence where: An input of no words produces the output string of just the two brace characters "{}". An input of just one word, e.g. ["AB...
#FreeBASIC
FreeBASIC
  ' FB 1.05.0 Win64   Sub Split(s As String, sep As String, result() As String) Dim As Integer i, j, count = 0 Dim temp As String Dim As Integer position(Len(s) + 1) position(0) = 0 For i = 0 To Len(s) - 1 For j = 0 To Len(sep) - 1 If s[i] = sep[j] Then count += 1 position(count) = ...
Give a code snippet in #FreeBASIC Comma quibbling is a task originally set by Eric Lippert in his blog. Task Write a function to generate a string output which is the concatenation of input words from a list/sequence where: An input of no words produces the output string of just the two brace characters "{}". A...
christopher/rosetta-code
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a sty...
#Excel
Excel
showAlphabet =LAMBDA(az, ENUMFROMTOCHAR( MID(az, 1, 1) )( MID(az, 2, 1) ) )
Give a code snippet in #Excel Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a ...
christopher/rosetta-code
http://rosettacode.org/wiki/Read_a_file_character_by_character/UTF8
Read a file character by character/UTF8
Task Read a file one character at a time, as opposed to reading the entire file at once. The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached). The procedure should support the reading of files contain...
#Phix
Phix
constant INVALID_UTF8 = #FFFD function get_one_utf8_char(integer fn) -- returns INVALID_UTF8 on error, else a string of 1..4 bytes representing one character object res integer headb, bytes, c -- headb = first byte of utf-8 character: headb = getc(fn) if headb=-1 then return -1 end if res = ""&headb...
Give a code snippet in #Phix Task Read a file one character at a time, as opposed to reading the entire file at once. The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached). The procedure should suppor...
christopher/rosetta-code
http://rosettacode.org/wiki/Long_multiplication
Long multiplication
Task Explicitly implement   long multiplication. This is one possible approach to arbitrary-precision integer algebra. For output, display the result of   264 * 264. Optionally, verify your result against builtin arbitrary precision support. The decimal representation of   264   is: 18,446,744,073,709,551,61...
#REXX
REXX
/*REXX program performs long multiplication on two numbers (without the "E"). */ numeric digits 300 /*be able to handle gihugeic input #s. */ parse arg x y . /*obtain optional arguments from the CL*/ if x=='' | x=="," then x= 2**64 ...
Give a code snippet in #REXX Task Explicitly implement   long multiplication. This is one possible approach to arbitrary-precision integer algebra. For output, display the result of   264 * 264. Optionally, verify your result against builtin arbitrary precision support. The decimal representation of   264   ...
christopher/rosetta-code
http://rosettacode.org/wiki/Polynomial_long_division
Polynomial long division
This page uses content from Wikipedia. The original article was at Polynomial long division. 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) In algebra, polynomial long division is an algorithm for d...
#REXX
REXX
/* REXX needed by some... */ z='1 -12 0 -42' /* Numerator */ n='1 -3' /* Denominator */ zx=z nx=n copies('0 ',words(z)-words(n)) qx='' /* Quotient */ Do Until words(zx)<words(n) Parse Value div(zx,nx) With q zx qx=qx q nx=subword(nx,1,words(nx)-1) End Say '('show(z)')/('show(n)')=('show...
Give a code snippet in #REXX This page uses content from Wikipedia. The original article was at Polynomial long division. 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) In algebra, polynomial long ...
christopher/rosetta-code
http://rosettacode.org/wiki/Superellipse
Superellipse
A superellipse is a geometric figure defined as the set of all points (x, y) with | x a | n + | y b | n = 1 , {\displaystyle \left|{\frac {x}{a}}\right|^{n}\!+\left|{\frac {y}{b}}\right|^{n}\!=1,} where n, a, and b are positive numbers. Task Draw a superellipse with n = 2.5, and a...
#Go
Go
package main   import ( "github.com/fogleman/gg" "math" )   /* assumes a and b are always equal */ func superEllipse(dc *gg.Context, n float64, a int) { hw := float64(dc.Width() / 2) hh := float64(dc.Height() / 2)   // calculate y for each x y := make([]float64, a+1) for x := 0; x <= a; x++ ...
Give a code snippet in #Go A superellipse is a geometric figure defined as the set of all points (x, y) with | x a | n + | y b | n = 1 , {\displaystyle \left|{\frac {x}{a}}\right|^{n}\!+\left|{\frac {y}{b}}\right|^{n}\!=1,} where n, a, and b are positive numbers. Task Draw a supe...
christopher/rosetta-code
http://rosettacode.org/wiki/Ray-casting_algorithm
Ray-casting algorithm
This page uses content from Wikipedia. The original article was at Point_in_polygon. 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) Given a point and a polygon, check if the point is inside or out...
#Python
Python
from collections import namedtuple from pprint import pprint as pp import sys   Pt = namedtuple('Pt', 'x, y') # Point Edge = namedtuple('Edge', 'a, b') # Polygon edge from a to b Poly = namedtuple('Poly', 'name, edges') # Polygon   _eps = 0.00001 _huge = sys.float_info.max _tiny = sys.float_i...
Give a code snippet in #Python This page uses content from Wikipedia. The original article was at Point_in_polygon. 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) Given a point and a polygon, che...
christopher/rosetta-code
http://rosettacode.org/wiki/Find_common_directory_path
Find common directory path
Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories. Test your routine using the forward slash '/' character as the directory separator and the foll...
#11l
11l
F find_common_directory_path(paths, sep = ‘/’) V pos = 0 L L(path) paths I pos < path.len & path[pos] == paths[0][pos] L.continue   L pos > 0 pos-- I paths[0][pos] == sep L.break R paths[0][0.<pos] pos++   print(find_common_...
Give a code snippet in #11l Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories. Test your routine using the forward slash '/' character as the dir...
christopher/rosetta-code
http://rosettacode.org/wiki/Sierpinski_carpet
Sierpinski carpet
Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## # # ## # # # ### ###### ...
#Raku
Raku
sub carpet { (['#'], -> @c { [ |@c.map({$_ x 3}), |@c.map({ $_ ~ $_.trans('#'=>' ') ~ $_}), |@c.map({$_ x 3}) ] } ... *).map: { .join("\n") }; }   say carpet[3];   # Same as above, structured as an array bound to a sequence, with a separate sub for clarity. sub weave ( @...
Give a code snippet in #Raku Task Produce a graphical or ASCII-art representation of a Sierpinski carpet of order   N. For example, the Sierpinski carpet of order   3   should look like this: ########################### # ## ## ## ## ## ## ## ## # ########################### ### ###### ###### ### # # # ## ...
christopher/rosetta-code
http://rosettacode.org/wiki/Regular_expressions
Regular expressions
Task   match a string against a regular expression   substitute part of a string using a regular expression
#Wren
Wren
import "/pattern" for Pattern   var s = "This is a story about R2D2 and C3P0 who are best friends." var p = Pattern.new("/u/d/u/d") var matches = p.findAll(s) System.print("Original string:\n%(" %(s)")")   System.print("\nThe following matches were found:") matches.each{ |m| System.print("  %(m.text) at index %(m.inde...
Give a code snippet in #Wren Task   match a string against a regular expression   substitute part of a string using a regular expression
christopher/rosetta-code
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture
Euler's sum of powers conjecture
There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin. Euler's (disproved) sum of powers   conjecture At least k positive kth powers are required to sum to a kth power, except for the trivial case...
#Julia
Julia
  const lim = 250 const pwr = 5 const p = [i^pwr for i in 1:lim]   x = zeros(Int, pwr-1) y = 0   for a in combinations(1:lim, pwr-1) b = searchsorted(p, sum(p[a])) 0 < length(b) || continue x = a y = b[1] break end   if y == 0 println("No solution found for power = ", pwr, " and limit = ", lim, ...
Give a code snippet in #Julia There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin. Euler's (disproved) sum of powers   conjecture At least k positive kth powers are required to sum to a kth power, ...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Bogosort
Sorting algorithms/Bogosort
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...
#Icon_and_Unicon
Icon and Unicon
procedure shuffle(l) repeat { !l :=: ?l suspend l } end   procedure sorted(l) local i if (i := 2 to *l & l[i] >= l[i-1]) then return &fail else return 1 end   procedure main() local l l := [6,3,4,5,1] |( shuffle(l) & sorted(l)) \1 & every writes(" ",!l) end
Give a code snippet in #Icon_and_Unicon Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort ...
christopher/rosetta-code
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#OCaml
OCaml
let to_vlq n = let a, b = n lsr 7, n land 0x7F in let rec aux n acc = let x = (n land 0x7F) lor 0x80 and xs = n lsr 7 in if xs > 0 then aux xs (x::acc) else x::acc in aux a [b]   let to_num = List.fold_left (fun n x -> n lsl 7 + (x land 0x7F)) 0   let v_rep n = Printf.printf "%d ->" n; l...
Give a code snippet in #OCaml Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert ...
christopher/rosetta-code
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#GML
GML
n = argument0 j = 1 for(i = 1; i <= n; i += 1) j *= i return j
Give a code snippet in #GML Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a num...
christopher/rosetta-code
http://rosettacode.org/wiki/JSON
JSON
Load a JSON string into a data structure. Also, create a new data structure and serialize it into JSON. Use objects and arrays (as appropriate for your language) and make sure your JSON is valid (https://jsonformatter.org).
#J
J
NB. character classes: NB. 0: whitespace NB. 1: " NB. 2: \ NB. 3: [ ] , { } : NB. 4: ordinary classes=.3<. '"\[],{}:' (#@[ |&>: i.) a. classes=.0 (I.a.e.' ',CRLF,TAB)} (]+4*0=])classes   words=:(0;(0 10#:10*".;._2]0 :0);classes)&;: NB. states: 0.0 1.1 2.1 3.1 4.1 NB. 0 whitespace 1.0 5.0 6.0 1...
Give a code snippet in #J Load a JSON string into a data structure. Also, create a new data structure and serialize it into JSON. Use objects and arrays (as appropriate for your language) and make sure your JSON is valid (https://jsonformatter.org).
christopher/rosetta-code
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,...
#FreeBASIC
FreeBASIC
' compile with: FBC -s console. ' compile with: FBC -s console -exx to have boundary checks.   Dim As Integer a(5) ' from s(0) to s(5) Dim As Integer num = 1 Dim As String s(-num To num) ' s1(-1), s1(0) and s1(1)   Static As UByte c(5) ' create a array with 6 elements (0 to 5)   'dimension array and initializing it ...
Give a code snippet in #FreeBASIC 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 r...
christopher/rosetta-code
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration
Convert seconds to compound duration
Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g., "2 hr, 59 sec"). Demonstrat...
#PL.2FI
PL/I
  /* Convert seconds to Compound Duration (weeks, days, hours, minutes, seconds). */   cvt: procedure options (main); /* 5 August 2015 */ declare interval float (15); declare (unit, i, q controlled) fixed binary; declare done bit (1) static initial ('0'b); declare name (5) character (4) varying static ini...
Give a code snippet in #PL.2FI Task Write a function or program which:   takes a positive integer representing a duration in seconds as input (e.g., 100), and   returns a string which shows the same duration decomposed into:   weeks,   days,   hours,   minutes,   and   seconds. This is detailed below (e.g....
christopher/rosetta-code
http://rosettacode.org/wiki/Pointers_and_references
Pointers and references
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Z80_Assembly
Z80 Assembly
ld a,(&C000) ;load the accumulator with the value from the memory address &C000.   ld hl,&D000 ld e,(hl) ;load the E register with the byte at memory address &D000.   ld bc,(&E000) ;load the register pair BC from memory address &E000. ; This is the same as: ; ld a,(&E000) ; ld c,a ; ld a,(&E001) ; ld b,a   ld ...
Give a code snippet in #Z80_Assembly Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Oper...
christopher/rosetta-code
http://rosettacode.org/wiki/Array_length
Array length
Task Determine the amount of elements in an array. As an example use an array holding the strings 'apple' and 'orange'. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I befo...
#Arturo
Arturo
fruit: ["apple" "orange"]   print ["array length =" size fruit]
Give a code snippet in #Arturo Task Determine the amount of elements in an array. As an example use an array holding the strings 'apple' and 'orange'. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter freq...
christopher/rosetta-code
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#ALGOL_68
ALGOL 68
STRING s := "12345"; FILE f; INT i; associate(f, s); get(f,i); i+:=1; s:=""; reset(f); put(f,i); print((s, new line))
Give a code snippet in #ALGOL_68 Task Increment a numerical string.
christopher/rosetta-code
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could ...
#Janet
Janet
(defmacro time "Print the time it takes to evaluate body to stderr.\n Evaluates to body." [body] (with-syms [$start $val] ~(let [,$start (os/clock) ,$val ,body] (eprint (- (os/clock) ,$start)) ,$val)))   (time (os/sleep 0.5))
Give a code snippet in #Janet Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between...
christopher/rosetta-code
http://rosettacode.org/wiki/Minkowski_question-mark_function
Minkowski question-mark function
The Minkowski question-mark function converts the continued fraction representation [a0; a1, a2, a3, ...] of a number into a binary decimal representation in which the integer part a0 is unchanged and the a1, a2, ... become alternating runs of binary zeroes and ones of those lengths. The decimal point takes the place o...
#Raku
Raku
# 20201120 Raku programming solution   my \MAXITER = 151;   sub minkowski(\x) {   return x.floor + minkowski( x - x.floor ) if x > 1 || x < 0 ;   my $y = my $p = x.floor; my ($q,$s,$d) = 1 xx 3; my $r = $p + 1;   loop { last if ( $y + ($d /= 2) == $y ) || ( my $m = $p + $r) < ...
Give a code snippet in #Raku The Minkowski question-mark function converts the continued fraction representation [a0; a1, a2, a3, ...] of a number into a binary decimal representation in which the integer part a0 is unchanged and the a1, a2, ... become alternating runs of binary zeroes and ones of those lengths. The d...
christopher/rosetta-code
http://rosettacode.org/wiki/Stair-climbing_puzzle
Stair-climbing puzzle
From Chung-Chieh Shan (LtU): Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function detects what happens and returns a...
#Smalltalk
Smalltalk
Smalltalk at: #stepUp put: 0. stepUp := [ [ step value ] whileFalse: [ stepUp value ] ].
Give a code snippet in #Smalltalk From Chung-Chieh Shan (LtU): Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function...
christopher/rosetta-code
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Haskell
Haskell
do {- ... -} throwIO SomeException
Give a code snippet in #Haskell Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptio...
christopher/rosetta-code
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...
#NewLISP
NewLISP
  (define (a-next a g) (mul 0.5 (add a g)))   (define (g-next a g) (sqrt (mul a g)))   (define (amg a g tolerance) (if (<= (sub a g) tolerance) a (amg (a-next a g) (g-next a g) tolerance) ) )   (define quadrillionth 0.000000000000001)   (define root-reciprocal-2 (div 1.0 (sqrt 2.0)))   (println "To the nearest ...
Give a code snippet in #NewLISP 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...
christopher/rosetta-code
http://rosettacode.org/wiki/Literals/String
Literals/String
Task Show literal specification of characters and strings. If supported, show how the following work:   verbatim strings   (quotes where escape sequences are quoted literally)   here-strings   Also, discuss which quotes expand variables. Related tasks   Special characters   Here document Other tasks r...
#BASIC
BASIC
10 LET Q$=CHR$(34): REM DOUBLEQUOTES 20 LET D$=Q$+Q$: REM A PAIR OF DOUBLEQUOTES 30 LET S$=Q$+"THIS IS A QUOTED STRING"+Q$ 40 PRINT Q$;"HELLO";Q$:REM ADD QUOTES DURING OUTPUT
Give a code snippet in #BASIC Task Show literal specification of characters and strings. If supported, show how the following work:   verbatim strings   (quotes where escape sequences are quoted literally)   here-strings   Also, discuss which quotes expand variables. Related tasks   Special characters  ...
christopher/rosetta-code
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#BBC_BASIC
BBC BASIC
INSTALL @lib$+"WINLIB2" INSTALL @lib$+"WINLIB5"   IDYES = 6 ES_NUMBER = 8192 MB_YESNO = 4   form% = FN_newdialog("Rosetta Code", 100, 100, 100, 52, 8, 1000) PROC_static(form%, "Value:", 100, 10, 10, 24, 14, 0) PROC_editbox(form%, "0", 101, 40, 8, 52, 14, ES_NUMBER) ...
Give a code snippet in #BBC_BASIC Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and che...
christopher/rosetta-code
http://rosettacode.org/wiki/Documentation
Documentation
See also Related task: Comments Related task: Here_document
#Kotlin
Kotlin
/** * A group of *members*. * @author A Programmer. * @since version 1.1.51. * * This class has no useful logic; it's just a documentation example. * * @param T the type of a member in this group. * @property name the name of this group. * @constructor Creates an empty group. */ class Group<T>(val name: Stri...
Give a code snippet in #Kotlin See also Related task: Comments Related task: Here_document
christopher/rosetta-code
http://rosettacode.org/wiki/Middle_three_digits
Middle three digits
Task Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible. Note: The order of the middle digits should be preserved. Your function should be tested with the following values;...
#Wart
Wart
def (mid3 n) withs (digits (with outstring # itoa (pr abs.n)) max len.digits mid (int max/2)) if (and odd?.max (max >= 3)) (digits mid-1 mid+2)
Give a code snippet in #Wart Task Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible. Note: The order of the middle digits should be preserved. Your function should be tes...
christopher/rosetta-code
http://rosettacode.org/wiki/Order_by_pair_comparisons
Order by pair comparisons
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...
#Wren
Wren
import "/ioutil" for Input import "/fmt" for Fmt   // Inserts item x in list a, and keeps it sorted assuming a is already sorted. // If x is already in a, inserts it to the right of the rightmost x. var insortRight = Fn.new{ |a, x, q| var lo = 0 var hi = a.count while (lo < hi) { var mid = ((lo + hi...
Give a code snippet in #Wren Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sor...
christopher/rosetta-code
http://rosettacode.org/wiki/Magnanimous_numbers
Magnanimous numbers
A magnanimous number is an integer where there is no place in the number where a + (plus sign) could be added between any two digits to give a non-prime sum. E.G. 6425 is a magnanimous number. 6 + 425 == 431 which is prime; 64 + 25 == 89 which is prime; 642 + 5 == 647 which is prime. 3538 is not a magnanimous numb...
#C
C
#include <stdio.h> #include <string.h>   typedef int bool; typedef unsigned long long ull;   #define TRUE 1 #define FALSE 0   /* OK for 'small' numbers. */ bool is_prime(ull n) { ull d; if (n < 2) return FALSE; if (!(n % 2)) return n == 2; if (!(n % 3)) return n == 3; d = 5; while (d * d <= n) ...
Give a code snippet in #C A magnanimous number is an integer where there is no place in the number where a + (plus sign) could be added between any two digits to give a non-prime sum. E.G. 6425 is a magnanimous number. 6 + 425 == 431 which is prime; 64 + 25 == 89 which is prime; 642 + 5 == 647 which is prime. 353...
christopher/rosetta-code
http://rosettacode.org/wiki/Multisplit
Multisplit
It is often necessary to split a string into pieces based on several different (potentially multi-character) separator strings, while still retaining the information about which separators were present in the input. This is particularly useful when doing small parsing tasks. The task is to write code to demonstrate ...
#Bracmat
Bracmat
( ( oneOf = operator .  !arg:%?operator ?arg & ( @(!sjt:!operator ?arg)&(!operator.!arg) | oneOf$!arg ) ) & "a!===b=!=c":?unparsed & "==" "!=" "=":?operators & whl ' ( @( !unparsed  : ?nonOp [%(oneOf$!operators:(?operator.?unparsed)) ) & put$(!nonOp str$("{" !operat...
Give a code snippet in #Bracmat It is often necessary to split a string into pieces based on several different (potentially multi-character) separator strings, while still retaining the information about which separators were present in the input. This is particularly useful when doing small parsing tasks. The task...
christopher/rosetta-code
http://rosettacode.org/wiki/Graph_colouring
Graph colouring
A Graph is a collection of nodes (or vertices), connected by edges (or not). Nodes directly connected by edges are called neighbours. In our representation of graphs, nodes are numbered and edges are represented by the two node numbers connected by the edge separated by a dash. Edges define the nodes being connected...
#Julia
Julia
using Random   """Useful constants for the colors to be selected for nodes of the graph""" const colors4 = ["blue", "red", "green", "yellow"] const badcolor = "black" @assert(!(badcolor in colors4))   """ struct graph   undirected simple graph constructed from its name and a string listing of point to point connect...
Give a code snippet in #Julia A Graph is a collection of nodes (or vertices), connected by edges (or not). Nodes directly connected by edges are called neighbours. In our representation of graphs, nodes are numbered and edges are represented by the two node numbers connected by the edge separated by a dash. Edges d...
christopher/rosetta-code
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...
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref savelog symbols binary   zigzag(5)   return   method zigzag(msize) public static   row = 1 col = 1   ziggy = Rexx(0) loop j_ = 0 for msize * msize ziggy[row, col] = j_ if (row + col) // 2 == 0 then do if col < msize then - col = c...
Give a code snippet in #NetRexx 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 e...
christopher/rosetta-code
http://rosettacode.org/wiki/Count_the_coins
Count the coins
There are four types of common coins in   US   currency:   quarters   (25 cents)   dimes   (10 cents)   nickels   (5 cents),   and   pennies   (1 cent) There are six ways to make change for 15 cents:   A dime and a nickel   A dime and 5 pennies   3 nickels   2 nickels and 5 pennies   A nickel and 10 pen...
#Clojure
Clojure
(def denomination-kind [1 5 10 25])   (defn- cc [amount denominations] (cond (= amount 0) 1 (or (< amount 0) (empty? denominations)) 0 :else (+ (cc amount (rest denominations)) (cc (- amount (first denominations)) denominations))))   (defn count-change "Calculates the number of time...
Give a code snippet in #Clojure There are four types of common coins in   US   currency:   quarters   (25 cents)   dimes   (10 cents)   nickels   (5 cents),   and   pennies   (1 cent) There are six ways to make change for 15 cents:   A dime and a nickel   A dime and 5 pennies   3 nickels   2 nickels and...
christopher/rosetta-code
http://rosettacode.org/wiki/Conjugate_transpose
Conjugate transpose
Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ( M H ) j i = M i j ...
#Sparkling
Sparkling
# Computes conjugate transpose of M let conjTransp = function conjTransp(M) { return map(range(sizeof M[0]), function(row) { return map(range(sizeof M), function(col) { return cplx_conj(M[col][row]); }); }); };   # Helper for cplxMatMul let cplxVecScalarMul = function cplxVecScalarMul(A, B, row, col) { var M ...
Give a code snippet in #Sparkling Suppose that a matrix M {\displaystyle M} contains complex numbers. Then the conjugate transpose of M {\displaystyle M} is a matrix M H {\displaystyle M^{H}} containing the complex conjugates of the matrix transposition of M {\displaystyle M} . ...
christopher/rosetta-code
http://rosettacode.org/wiki/Brilliant_numbers
Brilliant numbers
Brilliant numbers are a subset of semiprime numbers. Specifically, they are numbers that are the product of exactly two prime numbers that both have the same number of digits when expressed in base 10. Brilliant numbers are useful in cryptography and when testing prime factoring algorithms. E.G. 3 × 3 (9) is a bri...
#Java
Java
import java.util.*;   public class BrilliantNumbers { public static void main(String[] args) { var primesByDigits = getPrimesByDigits(100000000); System.out.println("First 100 brilliant numbers:"); List<Integer> brilliantNumbers = new ArrayList<>(); for (var primes : primesByDigits) ...
Give a code snippet in #Java Brilliant numbers are a subset of semiprime numbers. Specifically, they are numbers that are the product of exactly two prime numbers that both have the same number of digits when expressed in base 10. Brilliant numbers are useful in cryptography and when testing prime factoring algorithm...
christopher/rosetta-code
http://rosettacode.org/wiki/Flow-control_structures
Flow-control structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task Document common flow-control structures. One common example of a flow-control structure is the   goto   construct. Note that   Conditional Struc...
#FreeBASIC
FreeBASIC
  '$lang: "qb"   Gosub subrutina   bucle: Print "Bucle infinito" Goto bucle End   subrutina: Print "En subrutina" Sleep 100 Return Sleep  
Give a code snippet in #FreeBASIC Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task Document common flow-control structures. One common example of a flow-control structure is the   goto   constr...
christopher/rosetta-code
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#RapidQ
RapidQ
FOR i=1 TO 100 t$ = IIF(i MOD 3 = 0, "Fizz", "") + IIF(i MOD 5 = 0, "Buzz", "") PRINT IIF(LEN(t$), t$, i) NEXT i
Give a code snippet in #RapidQ Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuz...
christopher/rosetta-code
http://rosettacode.org/wiki/Menu
Menu
Task Given a prompt and a list containing a number of strings of which one is to be selected, create a function that: prints a textual menu formatted as an index value followed by its corresponding string for each item in the list; prompts the user to enter a number; returns the string corresponding to the selecte...
#Modula-2
Modula-2
MODULE Menu;   FROM InOut IMPORT WriteString, WriteCard, WriteLn, ReadCard;   CONST StringLength = 100; MenuSize = 4;   TYPE String = ARRAY[0..StringLength-1] OF CHAR;   VAR menu : ARRAY[0..MenuSize] OF String; selection, index : CARDINAL;   BEGIN menu[...
Give a code snippet in #Modula-2 Task Given a prompt and a list containing a number of strings of which one is to be selected, create a function that: prints a textual menu formatted as an index value followed by its corresponding string for each item in the list; prompts the user to enter a number; returns the s...
christopher/rosetta-code
http://rosettacode.org/wiki/One-dimensional_cellular_automata
One-dimensional cellular automata
Assume an array of cells with an initial distribution of live and dead cells, and imaginary cells off the end of the array having fixed values. Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation. If, in the follow...
#Erlang
Erlang
  -module(ca). -compile(export_all).   run(N,G) -> run(N,G,0).   run(GN,G,GN) -> io:fwrite("~B: ",[GN]), print(G); run(N,G,GN) -> io:fwrite("~B: ",[GN]), print(G), run(N,next(G),GN+1).   print([]) -> io:fwrite("~n"); print([0|T]) -> io:fwrite("_"), print(T); print([1|T]) -> io:fw...
Give a code snippet in #Erlang Assume an array of cells with an initial distribution of live and dead cells, and imaginary cells off the end of the array having fixed values. Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the curren...
christopher/rosetta-code
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#XPL0
XPL0
There are only three variable types: 32-bit signed integers (in the 32-bit version), IEEE-754 64-bit reals, and characters which are actually 32-bit addresses of (or pointers to) strings. When a 'char' variable is subscripted, it accesses a single byte. All variable names must be declared before they are used, for exam...
Give a code snippet in #XPL0 Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
christopher/rosetta-code
http://rosettacode.org/wiki/Truncate_a_file
Truncate a file
Task Truncate a file to a specific length.   This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes). Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating a temporary file of a reduced...
#VBScript
VBScript
  Sub truncate(fpath,n) 'Check if file exist Set objfso = CreateObject("Scripting.FileSystemObject") If objfso.FileExists(fpath) = False Then WScript.Echo fpath & " does not exist" Exit Sub End If content = "" 'stream the input file Set objinstream = CreateObject("Adodb.Stream") With objinstream .Type = 1...
Give a code snippet in #VBScript Task Truncate a file to a specific length.   This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes). Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by crea...
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Root_mean_square
Averages/Root mean square
Task[edit] Compute the   Root mean square   of the numbers 1..10. The   root mean square   is also known by its initials RMS (or rms), and as the quadratic mean. The RMS is calculated as the mean of the squares of the numbers, square-rooted: x r m s = x 1 2 + x 2 2 + ⋯ + x ...
#Lasso
Lasso
define rms(a::staticarray)::decimal => { return math_sqrt((with n in #a sum #n*#n) / decimal(#a->size)) } rms(generateSeries(1,10)->asStaticArray)
Give a code snippet in #Lasso Task[edit] Compute the   Root mean square   of the numbers 1..10. The   root mean square   is also known by its initials RMS (or rms), and as the quadratic mean. The RMS is calculated as the mean of the squares of the numbers, square-rooted: x r m s = x 1 2 ...
christopher/rosetta-code
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#SQL
SQL
  -- variable table DROP TABLE IF EXISTS var; CREATE temp TABLE var ( VALUE VARCHAR(1000) ); INSERT INTO var(VALUE) SELECT 'WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW';   -- select WITH recursive ints(num) AS ( SELECT 1 UNION ALL SELECT num+1 FROM ints WHERE num+1 <= LENGTH((SELECT VALUE ...
Give a code snippet in #SQL Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a functi...
christopher/rosetta-code
http://rosettacode.org/wiki/Julia_set
Julia set
Task Generate and draw a Julia set. Related tasks   Mandelbrot Set
#Kotlin
Kotlin
  import java.awt.* import java.awt.image.BufferedImage import javax.swing.JFrame import javax.swing.JPanel   class JuliaPanel : JPanel() { init { preferredSize = Dimension(800, 600) background = Color.white }   private val maxIterations = 300 private val zoom = 1 private val moveX =...
Give a code snippet in #Kotlin Task Generate and draw a Julia set. Related tasks   Mandelbrot Set
christopher/rosetta-code
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#JavaScript
JavaScript
function swap(arr) { var tmp = arr[0]; arr[0] = arr[1]; arr[1] = tmp; }
Give a code snippet in #JavaScript Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides gene...
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/With_multiple_ranges
Loops/With multiple ranges
Loops/With multiple ranges You are encouraged to solve this task according to the task description, using any language you may know. Some languages allow multiple loop ranges, such as the PL/I example (snippet) below. /* all variables are DECLARED as integers. */ prod=...
#Perl
Perl
use constant one => 1; use constant three => 3; use constant seven => 7; use constant x => 5; use constant yy => -5; # 'y' conflicts with use as equivalent to 'tr' operator (a carry-over from 'sed') use constant z => -2;   my $prod = 1;   sub from_to_by { my($begin,$end,$skip) = @_; my $n = 0; ...
Give a code snippet in #Perl Loops/With multiple ranges You are encouraged to solve this task according to the task description, using any language you may know. Some languages allow multiple loop ranges, such as the PL/I example (snippet) below. /* all variables are DECLARED a...
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Increment_loop_index_within_loop_body
Loops/Increment loop index within loop body
Sometimes, one may need   (or want)   a loop which its   iterator   (the index variable)   is modified within the loop body   in addition to the normal incrementation by the   (do)   loop structure index. Goal Demonstrate the best way to accomplish this. Task Write a loop which:   starts the index (variable...
#Phix
Phix
atom i=42, n=1 while n<=42 do if is_prime(i) then printf(1,"n = %-2d  %,19d\n", {n, i}) n += 1 i += i-1 end if i += 1 end while
Give a code snippet in #Phix Sometimes, one may need   (or want)   a loop which its   iterator   (the index variable)   is modified within the loop body   in addition to the normal incrementation by the   (do)   loop structure index. Goal Demonstrate the best way to accomplish this. Task Write a loop which: ...
christopher/rosetta-code
http://rosettacode.org/wiki/Dutch_national_flag_problem
Dutch national flag problem
The Dutch national flag is composed of three coloured bands in the order:   red     (top)   then white,   and   lastly blue   (at the bottom). The problem posed by Edsger Dijkstra is: Given a number of red, blue and white balls in random order, arrange them in the order of the colours in the Dutch national fla...
#Logo
Logo
; We'll just use words for the balls make "colors {red white blue}   ; to get a mapping from colors back to a numeric value, ; we make variables out of the color names (e.g. the variable ; "red" has value "1"). foreach arraytolist :colors [ make ? # ]   ; Make a random list of a given size to random_balls :n local ...
Give a code snippet in #Logo The Dutch national flag is composed of three coloured bands in the order:   red     (top)   then white,   and   lastly blue   (at the bottom). The problem posed by Edsger Dijkstra is: Given a number of red, blue and white balls in random order, arrange them in the order of the col...
christopher/rosetta-code
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#.D0.9C.D0.9A-61.2F52
МК-61/52
6 ПП 04 П7 КПП7 В/О 1 В/О
Give a code snippet in #.D0.9C.D0.9A-61.2F52 Task Pass a function     as an argument     to another function. Related task   First-class functions
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Mode
Averages/Mode
Task[edit] Write a program to find the mode value of a collection. The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique. If it is not appropriate or possible to support a general collection, use a vector (array), if possible. If it is not appropriat...
#S-lang
S-lang
private variable mx, mxkey, modedat;   define find_max(key) { if (modedat[key] > mx) { mx = modedat[key]; mxkey = {key}; } else if (modedat[key] == mx) { list_append(mxkey, key); } }   define find_mode(indat) {  % reset [file/module-scope] globals: mx = 0, mxkey = {}, modedat = Assoc_Type[Int_Typ...
Give a code snippet in #S-lang Task[edit] Write a program to find the mode value of a collection. The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique. If it is not appropriate or possible to support a general collection, use a vector (array), if p...
christopher/rosetta-code
http://rosettacode.org/wiki/Pointers_and_references
Pointers and references
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Delphi
Delphi
pMyPointer : Pointer ;
Give a code snippet in #Delphi Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations...
christopher/rosetta-code
http://rosettacode.org/wiki/Number_names
Number names
Task Show how to spell out a number in English. You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less). Support for inputs other than positive integers (like zero, negat...
#Applesoft_BASIC
Applesoft BASIC
10 INPUT "GIMME A NUMBER! "; N 20 GOSUB 100"NUMBER NAME 30 PRINT R$ 40 END   100 REMNUMBER NAME 110 IF R$ = "" THEN FOR I = 0 TO 10 : READ S$(I), T$(I), U$(I), V$(I) : NEXT 120 IF N = 0 THEN R$ = "ZERO" : RETURN 130 R$ = "" : D = 10 : C = 100 : M = 1E3 140 A = ABS(N) 150 FOR U = 0 TO D 160 H = A - C * INT(A / C) 17...
Give a code snippet in #Applesoft_BASIC Task Show how to spell out a number in English. You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less). Support for inputs other...
christopher/rosetta-code
http://rosettacode.org/wiki/S-expressions
S-expressions
S-Expressions   are one convenient way to parse and store data. Task Write a simple reader and writer for S-Expressions that handles quoted and unquoted strings, integers and floats. The reader should read a single but nested S-Expression from a string and store it in a suitable datastructure (list, array, etc). ...
#C.2B.2B
C++
#include <cctype> #include <iomanip> #include <iostream> #include <list> #include <memory> #include <sstream> #include <string> #include <variant>   namespace s_expr {   enum class token_type { none, left_paren, right_paren, symbol, string, number }; enum class char_type { left_paren, right_paren, quote, escape, space,...
Give a code snippet in #C.2B.2B S-Expressions   are one convenient way to parse and store data. Task Write a simple reader and writer for S-Expressions that handles quoted and unquoted strings, integers and floats. The reader should read a single but nested S-Expression from a string and store it in a suitable da...
christopher/rosetta-code
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#zkl
zkl
fcn fact(n){[2..n].reduce('*,1)} fcn factTail(n,N=1) { // tail recursion if (n == 0) return(N); return(self.fcn(n-1,n*N)); }
Give a code snippet in #zkl Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a num...
christopher/rosetta-code
http://rosettacode.org/wiki/Dining_philosophers
Dining philosophers
The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra. Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou...
#JoCaml
JoCaml
let random_wait n = Unix.sleep (Random.int n);; let print s m = Printf.printf "philosopher %s is %s\n" s m; flush(stdout);; let will_eat s = print s "eating"; random_wait 10;; let will_think s = print s "thinking"; random_wait 20; print s "hungry";;   (* a,b,c,d,e are thinking philosophers; ah,bh,ch,dh,eh are the sam...
Give a code snippet in #JoCaml The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra. Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eat...
christopher/rosetta-code
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 ...
#Prolog
Prolog
  product(A, B, C) :- C is A*B.   pair(X, Y, X-Y).   egcd(_, 0, 1, 0) :- !. egcd(A, B, X, Y) :- divmod(A, B, Q, R), egcd(B, R, S, X), Y is S - Q*X.   modinv(A, B, X) :- egcd(A, B, X, Y), A*X + B*Y =:= 1.   crt_fold(A, M, P, R0, R1) :- % system of equations of (x = a) (mod m); p = M/m modinv(P, M...
Give a code snippet in #Prolog 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 {\display...
christopher/rosetta-code
http://rosettacode.org/wiki/Rate_counter
Rate counter
Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus. Multiple approaches are allowed (even preferable), so long as they can accomplish these goals: Run N seconds worth...
#Nim
Nim
import sugar, std/monotimes, times   type Func[T] = (T) -> T   func cube(n: int): int = n * n * n   proc benchmark[T](n: int; f: Func[T]; arg: T): seq[Duration] = result.setLen(n) for i in 0..<n: let m = getMonoTime() discard f(arg) result[i] = getMonoTime() - m   echo "Timings (nanoseconds):" for time ...
Give a code snippet in #Nim Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus. Multiple approaches are allowed (even preferable), so long as they can accomplish these...
christopher/rosetta-code
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#M2000_Interpreter
M2000 Interpreter
  Module checkit { class Vector { \\ by default are double a,b,c Property ToString$ { Value { link parent a,b,c to a,b,c value$=format$("({0}, {1}, {2})",a,b,c) ...
Give a code snippet in #M2000_Interpreter A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a t...
christopher/rosetta-code