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http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Sidef
Sidef
for n in (1 .. 2**19) { var frac = 0   n.divisors.each {|d| frac += 1/d }   if (frac.is_int) { say "Sum of reciprocal divisors of #{n} = #{frac} exactly #{ frac == 2 ? '- perfect!' : '' }" } }
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Lua
Lua
print(0^0)
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#M2000_Interpreter
M2000 Interpreter
  Module Checkit { x=0 y=0 Print x**y=1, x^y=1 ' True True } Checkit  
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Maple
Maple
0^0
http://rosettacode.org/wiki/Zebra_puzzle
Zebra puzzle
Zebra puzzle You are encouraged to solve this task according to the task description, using any language you may know. The Zebra puzzle, a.k.a. Einstein's Riddle, is a logic puzzle which is to be solved programmatically. It has several variants, one of them this:   There are five houses.   The English man lives ...
#AutoHotkey
AutoHotkey
REM The names (only used for printing the results): DIM Drink$(4), Nation$(4), Colr$(4), Smoke$(4), Animal$(4) Drink$() = "Beer", "Coffee", "Milk", "Tea", "Water" Nation$() = "Denmark", "England", "Germany", "Norway", "Sweden" Colr$() = "Blue", "Green", "Red", "White", "Yellow" Sm...
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#ARM_Assembly
ARM Assembly
  /* ARM assembly Raspberry PI */ /* program xpathXml.s */   /* Constantes */ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ WRITE, 4 @ Linux syscall   .equ NBMAXELEMENTS, 100   /*******************************************/ /* Structures */...
http://rosettacode.org/wiki/Yin_and_yang
Yin and yang
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu. Task   Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.   Generate and display the symbol for two different (small) sizes.
#ARM_Assembly
ARM Assembly
  /* ARM assembly Raspberry PI */ /* program yingyang.s */   /* REMARK 1 : this program use routines in a include file see task Include a file language arm assembly for the routine affichageMess conversion10 see at end of this program the instruction include */ /*****************************************...
http://rosettacode.org/wiki/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#ATS
ATS
  (* ****** ****** *) // #include "share/atspre_staload.hats" // (* ****** ****** *) // fun myfix {a:type} ( f: lazy(a) -<cloref1> a ) : lazy(a) = $delay(f(myfix(f))) // val fact = myfix{int-<cloref1>int} ( lam(ff) => lam(x) => if x > 0 then x * !ff(x-1) else 1 ) (* ****** ****** *) // implement main0 () = println! ("...
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...
#AutoHotkey
AutoHotkey
n = 5 ; size v := x := y := 1 ; initial values Loop % n*n { ; for every array element a_%x%_%y% := v++ ; assign the next index If ((x+y)&1) ; odd diagonal If (x < n) ; while inside the square y -=...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#JavaScript
JavaScript
(() => { 'use strict';   // yellowstone :: Generator [Int] function* yellowstone() { // A non finite stream of terms in the // Yellowstone permutation of the natural numbers. // OEIS A098550 const nextWindow = ([p2, p1, rest]) => { const [rp2, rp1] = [p2, p1].map(...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#Icon_and_Unicon
Icon and Unicon
link printf,strings   procedure main() YS := YahooSearch("rosettacode") every 1 to 2 do { # 2 pages YS.readnext() YS.showinfo() } end   class YahooSearch(urlpat,page,response) #: class for Yahoo Search   method readnext() #: read the next page of search results self.page +:= 1 # can't find as...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#TXR
TXR
@(next :args) @(define space)@/ */@(end) @(define mulop (nod))@\ @(local op)@\ @(space)@\ @(cases)@\ @{op /[*]/}@(bind nod @(intern op *user-package*))@\ @(or)@\ @{op /\//}@(bind (nod) @(list 'trunc))@\ @(end)@\ @(space)@\ @(end) @(define addop (nod))@\ @(local op)@(space)@{op /[+\-]/}@(s...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Ursala
Ursala
#import std #import nat #import flo   lex = ~=' '*~F+ rlc both -=digits # separate into tokens   parse = # build a tree   --<';'>; @iNX ~&l->rh ^/~&lt cases~&lhh\~&lhPNVrC { '*/': ^|C/~&hNV associate '*/', '+-': ^|C/~&hNV associate '*/+-', ');': @r ~&htitBPC+ associate '*/+-'}   associate "ops" = ~&tihdh2B-...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Vlang
Vlang
import strings const ( dig = ["00", "01", "10"] dig1 = ["", "1", "10"] )   struct Zeckendorf { mut: d_val int d_len int }   fn new_zeck(xx string) Zeckendorf { mut z := Zeckendorf{} mut x := xx if x == "" { x = "0" } mut q := 1 mut i := x.len - 1 z.d_len = i / 2 ...
http://rosettacode.org/wiki/Zeckendorf_arithmetic
Zeckendorf arithmetic
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation. The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions. Addition Like bin...
#Wren
Wren
import "/trait" for Comparable   class Zeckendorf is Comparable { static dig { ["00", "01", "10"] } static dig1 { ["", "1", "10"] }   construct new(x) { var q = 1 var i = x.count - 1 _dLen = (i / 2).floor _dVal = 0 while (i >= 0) { _dVal = _dVal + (x[i].b...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Ring
Ring
  load "stdlib.ring"   see "working..." + nl see "The first 220 Zumkeller numbers are:" + nl   permut = [] zumind = [] zumodd = [] limit = 19305 num1 = 0 num2 = 0   for n = 2 to limit zumkeller = [] zumList = [] permut = [] calmo = [] zumind = [] num = 0 nold = 0 for m = 1 to n i...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Ruby
Ruby
class Integer   def divisors res = [1, self] (2..Integer.sqrt(self)).each do |n| div, mod = divmod(n) res << n << div if mod.zero? end res.uniq.sort end   def zumkeller? divs = divisors sum = divs.sum return false unless sum.even? && sum >= self*2 half = sum / 2 ma...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Frink
Frink
a = 5^4^3^2 as = "$a" // Coerce to string println["Length=" + length[as] + ", " + left[as,20] + "..." + right[as,20]]
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#F.C5.8Drmul.C3.A6
Fōrmulæ
n:=5^(4^(3^2));; s := String(n);; m := Length(s); # 183231 s{[1..20]}; # "62060698786608744707" s{[m-19..m]}; # "92256259918212890625"
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#GAP
GAP
n:=5^(4^(3^2));; s := String(n);; m := Length(s); # 183231 s{[1..20]}; # "62060698786608744707" s{[m-19..m]}; # "92256259918212890625"
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Ruby
Ruby
class ZhangSuen NEIGHBOUR8 = [[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1],[-1,-1]] # 8 neighbors CIRCULARS = NEIGHBOUR8 + [NEIGHBOUR8.first] # P2, ... P9, P2 def initialize(str, black="#") s1 = str.each_line.map{|line| line.chomp.each_char.map{|c| c==black ? 1 : 0}} s2 = s1.map{|l...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Java
Java
import java.util.*;   class Zeckendorf { public static String getZeckendorf(int n) { if (n == 0) return "0"; List<Integer> fibNumbers = new ArrayList<Integer>(); fibNumbers.add(1); int nextFib = 2; while (nextFib <= n) { fibNumbers.add(nextFib); nextFib += fibNumbers.get(fi...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#CLIPS
CLIPS
(deffacts initial-state (door-count 100) )   (deffunction toggle (?state) (switch ?state (case "open" then "closed") (case "closed" then "open") ) )   (defrule create-doors-and-visits (door-count ?count) => (loop-for-count (?num 1 ?count) do (assert (door ?num "closed")) (assert (visit-fro...
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,...
#Forth
Forth
create MyArray 1 , 2 , 3 , 4 , 5 , 5 cells allot here constant MyArrayEnd   30 MyArray 7 cells + ! MyArray 7 cells + @ . \ 30   : .array MyArrayEnd MyArray do I @ . cell +loop ;
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#REXX
REXX
/*REXX program demonstrates how to support some math functions for complex numbers. */ x = '(5,3i)' /*define X ─── can use I i J or j */ y = "( .5, 6j)" /*define Y " " " " " " " */   say ' addition: ' x " + ...
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Slate
Slate
54 / 7. 20 reciprocal. (5 / 6) reciprocal. (5 / 6) as: Float.
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
0^0
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#MATLAB_.2F_Octave
MATLAB / Octave
0^0 complex(0,0)^0
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Maxima
Maxima
0^0;
http://rosettacode.org/wiki/Zebra_puzzle
Zebra puzzle
Zebra puzzle You are encouraged to solve this task according to the task description, using any language you may know. The Zebra puzzle, a.k.a. Einstein's Riddle, is a logic puzzle which is to be solved programmatically. It has several variants, one of them this:   There are five houses.   The English man lives ...
#BBC_BASIC
BBC BASIC
REM The names (only used for printing the results): DIM Drink$(4), Nation$(4), Colr$(4), Smoke$(4), Animal$(4) Drink$() = "Beer", "Coffee", "Milk", "Tea", "Water" Nation$() = "Denmark", "England", "Germany", "Norway", "Sweden" Colr$() = "Blue", "Green", "Red", "White", "Yellow" Sm...
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#AutoHotkey
AutoHotkey
FileRead, inventory, xmlfile.xml   RegExMatch(inventory, "<item.*?</item>", item1) MsgBox % item1   pos = 1 While, pos := RegExMatch(inventory, "<price>(.*?)</price>", price, pos + 1) MsgBox % price1   While, pos := RegExMatch(inventory, "<name>.*?</name>", name, pos + 1) names .= name . "`n" MsgBox % names
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#Bracmat
Bracmat
{Retrieve the first "item" element} ( nestML$(get$("doc.xml",X,ML))  :  ? ( inventory . ?,? (section.?,? ((item.?):?item) ?) ? )  ? & out$(toML$!item) )   {Perform an action on each "price" element (print it out)} ( nestML$(get$("doc.xml",X,ML))  :  ? ( inventory .  ? ...
http://rosettacode.org/wiki/Yin_and_yang
Yin and yang
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu. Task   Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.   Generate and display the symbol for two different (small) sizes.
#Asymptote
Asymptote
unitsize(1 inch);   fill(scale(6)*unitsquare, invisible);   picture yinyang(pair center, real radius) { picture p; fill(p, unitcircle, white); fill(p, arc(0, S, N) -- cycle, black); fill(p, circle(N/2, 1/2), white); fill(p, circle(S/2, 1/2), black); fill(p, circle(N/2, 1/5), black); fill(p, ...
http://rosettacode.org/wiki/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#BlitzMax
BlitzMax
SuperStrict   'Boxed type so we can just use object arrays for argument lists Type Integer Field val:Int Function Make:Integer(_val:Int) Local i:Integer = New Integer i.val = _val Return i End Function End Type     'Higher-order function type - just a procedure attached to a scope Type Func Abstract Method ap...
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...
#AutoIt
AutoIt
  #include <Array.au3> $Array = ZigZag(5) _ArrayDisplay($Array)   Func ZigZag($int) Local $av_array[$int][$int] Local $x = 1, $y = 1 For $I = 0 To $int ^ 2 -1 $av_array[$x-1][$y-1] = $I If Mod(($x + $y), 2) = 0 Then ;Even if ($y < $int) Then $y += 1 Else $x += 2 EndIf if ($x > 1) Then $x -= 1...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#jq
jq
  # jq optimizes the recursive call of _gcd in the following: def gcd(a;b): def _gcd: if .[1] != 0 then [.[1], .[0] % .[1]] | _gcd else .[0] end; [a,b] | _gcd ;   # emit the yellowstone sequence as a stream def yellowstone: 1,2,3, ({ a: [2, 3], # the last two items only b:...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#Julia
Julia
using Plots   function yellowstone(N) a = [1, 2, 3] b = Dict(1 => 1, 2 => 1, 3 => 1) start = 4 while length(a) < N inseries = true for i in start:typemax(Int) if haskey(b, i) if inseries start += 1 end else ...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#Java
Java
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.MalformedURLException; import java.net.URISyntaxException; import java.net.URL; import java.net.URLDecoder; import java.net.URLEncoder; import java.util.ArrayList; import java.util.List; import java.util.regex.M...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#Wren
Wren
import "/pattern" for Pattern   /* if string is empty, returns zero */ var toDoubleOrZero = Fn.new { |s| var n = Num.fromString(s) return n ? n : 0 }   var multiply = Fn.new { |s| var b = s.split("*").map { |t| toDoubleOrZero.call(t) }.toList return (b[0] * b[1]).toString }   var divide = Fn.new { |s| ...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Rust
Rust
  use std::convert::TryInto;   /// Gets all divisors of a number, including itself fn get_divisors(n: u32) -> Vec<u32> { let mut results = Vec::new();   for i in 1..(n / 2 + 1) { if n % i == 0 { results.push(i); } } results.push(n); results }   /// Calculates whether the ...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Sidef
Sidef
func is_Zumkeller(n) {   return false if n.is_prime return false if n.is_square   var sigma = n.sigma   # n must have an even abundance return false if (sigma.is_odd || (sigma < 2*n))   # true if n is odd and has an even abundance return true if n.is_odd # conjecture   var divisors = ...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Go
Go
package main   import ( "fmt" "math/big" )   func main() { x := big.NewInt(2) x = x.Exp(big.NewInt(3), x, nil) x = x.Exp(big.NewInt(4), x, nil) x = x.Exp(big.NewInt(5), x, nil) str := x.String() fmt.Printf("5^(4^(3^2)) has %d digits: %s ... %s\n", len(str), str[:20], str[len(str)-20:], ) }
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Sidef
Sidef
class ZhangSuen(str, black="1") { const NEIGHBOURS = [[-1,0],[-1,1],[0,1],[1,1],[1,0],[1,-1],[0,-1],[-1,-1]] # 8 neighbors const CIRCULARS = (NEIGHBOURS + [NEIGHBOURS.first]) # P2, ... P9, P2   has r = 0 has image = [[]]   method init { var s1 = str.lines.map{|line| line.chars.map...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#JavaScript
JavaScript
(() => { 'use strict';   const main = () => unlines( map(n => concat(zeckendorf(n)), enumFromTo(0, 20) ) );   // zeckendorf :: Int -> String const zeckendorf = n => { const go = (n, x) => n < x ? ( Tuple(n, '0') ...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#Clojure
Clojure
(defn doors [] (let [doors (into-array (repeat 100 false))] (doseq [pass (range 1 101) i (range (dec pass) 100 pass) ] (aset doors i (not (aget doors i)))) doors))   (defn open-doors [] (for [[d n] (map vector (doors) (iterate inc 1)) :when d] n))   (defn print-open-doors [] (pr...
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,...
#Fortran
Fortran
integer a (10)
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#RLaB
RLaB
  >> x = sqrt(-1) 0 + 1i >> y = 10 + 5i 10 + 5i >> z = 5*x-y -10 + 0i >> isreal(z) 1  
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Smalltalk
Smalltalk
st> 54/7 54/7 st> 54/7 + 1 61/7 st> 54/7 < 50 true st> 20 reciprocal 1/20 st> (5/6) reciprocal 6/5 st> (5/6) asFloat 0.8333333333333334
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Mercury
Mercury
:- module zero_to_the_zero_power. :- interface.   :- import_module io.   :- pred main(io::di, io::uo) is det.   :- implementation.   :- import_module float, int, integer, list, string.   main(!IO) :- io.format(" int.pow(0, 0) = %d\n", [i(pow(0, 0))], !IO), io.format("integer.pow(zero, zero) = %s\n", [s...
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Microsoft_Small_Basic
Microsoft Small Basic
TextWindow.WriteLine(Math.Power(0,0))
http://rosettacode.org/wiki/Zebra_puzzle
Zebra puzzle
Zebra puzzle You are encouraged to solve this task according to the task description, using any language you may know. The Zebra puzzle, a.k.a. Einstein's Riddle, is a logic puzzle which is to be solved programmatically. It has several variants, one of them this:   There are five houses.   The English man lives ...
#Bracmat
Bracmat
( (English Swede Dane Norwegian German,) (red green white yellow blue,(red.English.)) (dog birds cats horse zebra,(dog.?.Swede.)) ( tea coffee milk beer water , (tea.?.?.Dane.) (coffee.?.green.?.) ) ( "Pall Mall" Dunhill Blend "Blue Master" Prince , ("Blue Master".beer.?....
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#C
C
  #include <libxml/parser.h> #include <libxml/xpath.h>   xmlDocPtr getdoc (char *docname) { xmlDocPtr doc; doc = xmlParseFile(docname);   return doc; }   xmlXPathObjectPtr getnodeset (xmlDocPtr doc, xmlChar *xpath){   xmlXPathContextPtr context; xmlXPathObjectPtr result;   context = xmlXPathNewContext(doc);   re...
http://rosettacode.org/wiki/Yin_and_yang
Yin and yang
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu. Task   Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.   Generate and display the symbol for two different (small) sizes.
#AutoHotkey
AutoHotkey
Yin_and_Yang(50, 50, A_ScriptDir "\YinYang1.png") Yin_and_Yang(300, 300,A_ScriptDir "\YinYang2.png")   Yin_and_Yang(width, height, fileName , color1=0xFFFFFFFF, color2=0xFF000000, outlineWidth=1){   pToken := gdip_Startup() pBitmap := gdip_CreateBitmap(w := width, h := height) w-=1, h-=1 pGraphics:= gdip_Graph...
http://rosettacode.org/wiki/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#Bracmat
Bracmat
(λx.x)y
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...
#AWK
AWK
  # syntax: GAWK -f ZIG-ZAG_MATRIX.AWK [-v offset={0|1}] [size] BEGIN { # offset: "0" prints 0 to size^2-1 while "1" prints 1 to size^2 offset = (offset == "") ? 0 : offset size = (ARGV[1] == "") ? 5 : ARGV[1] if (offset !~ /^[01]$/) { exit(1) } if (size !~ /^[0-9]+$/) { exit(1) } width = length(siz...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#Kotlin
Kotlin
fun main() { println("First 30 values in the yellowstone sequence:") println(yellowstoneSequence(30)) }   private fun yellowstoneSequence(sequenceCount: Int): List<Int> { val yellowstoneList = mutableListOf(1, 2, 3) var num = 4 val notYellowstoneList = mutableListOf<Int>() var yellowSize = 3 ...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#Julia
Julia
""" Rosetta Code Yahoo search task. https://rosettacode.org/wiki/Yahoo!_search_interface """   using EzXML using HTTP using Logging   const pagesize = 7 const URI = "https://search.yahoo.com/search?fr=opensearch&pz=$pagesize&"   struct SearchResults title::String content::String url::String end   mutable st...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#Kotlin
Kotlin
// version 1.2.0   import java.net.URL   val rx = Regex("""<div class=\"yst result\">.+?<a href=\"(.*?)\" class=\"\">(.*?)</a>.+?class="abstract ellipsis">(.*?)</p>""")   class YahooResult(var title: String, var link: String, var text: String) {   override fun toString() = "\nTitle: $title\nLink : $link\nText : $te...
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#zkl
zkl
Compiler.Parser.parseText("(1+3)*7").dump(); Compiler.Parser.parseText("1+3*7").dump();
http://rosettacode.org/wiki/Arithmetic_evaluation
Arithmetic evaluation
Create a program which parses and evaluates arithmetic expressions. Requirements An abstract-syntax tree (AST) for the expression must be created from parsing the input. The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.) The ...
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 PRINT "Use integer numbers and signs"'"+ - * / ( )"'' 20 LET s$="": REM last symbol 30 LET pc=0: REM parenthesis counter 40 LET i$="1+2*(3+(4*5+6*7*8)-9)/10" 50 PRINT "Input = ";i$ 60 FOR n=1 TO LEN i$ 70 LET c$=i$(n) 80 IF c$>="0" AND c$<="9" THEN GO SUB 170: GO TO 130 90 IF c$="+" OR c$="-" THEN GO SUB 200: GO TO ...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Standard_ML
Standard ML
  exception Found of string ;   val divisors = fn n => let val rec divr = fn ( c, divlist ,i) => if c <2*i then c::divlist else divr (if c mod i = 0 then (c,i::divlist,i+1) else (c,divlist,i+1) ) in divr (n,[],1) end;     val subsetSums = fn M => fn input => let val getnrs = fn (v,x) => ...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Swift
Swift
import Foundation   extension BinaryInteger { @inlinable public var isZumkeller: Bool { let divs = factors(sorted: false) let sum = divs.reduce(0, +)   guard sum & 1 != 1 else { return false }   guard self & 1 != 1 else { let abundance = sum - 2*self   return abundance > 0 && a...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Golfscript
Golfscript
5 4 3 2??? # Calculate 5^(4^(3^2)) `.. # Convert to string and make two copies 20<p # Print the first 20 digits -20>p # Print the last 20 digits ,p # Print the length
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Groovy
Groovy
def bigNumber = 5G ** (4 ** (3 ** 2))
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Haskell
Haskell
main :: IO () main = do let y = show (5 ^ 4 ^ 3 ^ 2) let l = length y putStrLn ("5**4**3**2 = " ++ take 20 y ++ "..." ++ drop (l - 20) y ++ " and has " ++ show l ++ " digits")
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Swift
Swift
import UIKit   // testing examples let beforeTxt = """ 1100111 1100111 1100111 1100111 1100110 1100110 1100110 1100110 1100110 1100110 1100110 1100110 1111110 0000000 """   let smallrc01 = """ 00000000000000000000000000000000 01111111110000000111111110000000 01110001111000001111001111000000 0111000011100000111000011100...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#jq
jq
def zeckendorf: def fibs($n): # input: [f(i-2), f(i-1)] [1,1] | [recurse(select(.[1] < $n) | [.[1], add]) | .[1]] ;   # Emit an array of 0s and 1s corresponding to the Zeckendorf encoding # $f should be the relevant Fibonacci numbers in increasing order. def loop($f): [ recurse(. as [$n, $ix] ...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Julia
Julia
function zeck(n) n <= 0 && return 0 fib = [2,1]; while fib[1] < n unshift!(fib,sum(fib[1:2])) end dig = Int[]; for f in fib f <= n ? (push!(dig,1); n = n-f;) : push!(dig,0) end return dig[1] == 0 ? dig[2:end] : dig end
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#CLU
CLU
start_up = proc () max = 100 po: stream := stream$primary_output() open: array[bool] := array[bool]$fill(1, max, false)   for pass: int in int$from_to(1, max) do for door: int in int$from_to_by(pass, max, pass) do open[door] := ~open[door] end end   for door: int in a...
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 ...
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Ruby
Ruby
  # Four ways to write complex numbers: a = Complex(1, 1) # 1. call Kernel#Complex i = Complex::I # 2. use Complex::I b = 3.14159 + 1.25 * i c = '1/2+3/4i'.to_c # 3. Use the .to_c method from String, result ((1/2)+(3/4)*i) c = 1.0/2+3/4i # (0.5-(3/4)*i)   # Operations: puts a + b ...
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Swift
Swift
import Foundation   extension BinaryInteger { @inlinable public func gcd(with other: Self) -> Self { var gcd = self var b = other   while b != 0 { (gcd, b) = (b, gcd % b) }   return gcd }   @inlinable public func lcm(with other: Self) -> Self { let g = gcd(with: other)   retu...
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#min
min
0 0 pow puts
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#MiniScript
MiniScript
print "The result of zero to the zero power is " + 0^0
http://rosettacode.org/wiki/Zebra_puzzle
Zebra puzzle
Zebra puzzle You are encouraged to solve this task according to the task description, using any language you may know. The Zebra puzzle, a.k.a. Einstein's Riddle, is a logic puzzle which is to be solved programmatically. It has several variants, one of them this:   There are five houses.   The English man lives ...
#C
C
#include <stdio.h> #include <string.h>   enum HouseStatus { Invalid, Underfull, Valid };   enum Attrib { C, M, D, A, S };   // Unfilled attributes are represented by -1 enum Colors { Red, Green, White, Yellow, Blue }; enum Mans { English, Swede, Dane, German, Norwegian }; enum Drinks { Tea, Coffee, Milk, Beer, Water };...
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#C.23
C#
XmlReader XReader;   // Either read the xml from a string ... XReader = XmlReader.Create(new StringReader("<inventory title=... </inventory>"));   // ... or read it from the file system. XReader = XmlReader.Create("xmlfile.xml");   // Create a XPathDocument object (which implements the IXPathNavigable interface) // whi...
http://rosettacode.org/wiki/Yin_and_yang
Yin and yang
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu. Task   Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.   Generate and display the symbol for two different (small) sizes.
#AWK
AWK
  # syntax: GAWK -f YIN_AND_YANG.AWK # converted from PHL BEGIN { yin_and_yang(16) yin_and_yang(8) exit(0) } function yin_and_yang(radius, black,white,scale_x,scale_y,sx,sy,x,y) { black = "#" white = "." scale_x = 2 scale_y = 1 for (sy = radius*scale_y; sy >= -(radius*scale_y); sy--) { ...
http://rosettacode.org/wiki/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#C
C
#include <stdio.h> #include <stdlib.h>   /* func: our one and only data type; it holds either a pointer to a function call, or an integer. Also carry a func pointer to a potential parameter, to simulate closure */ typedef struct func_t *func; typedef struct func_t { func (*fn) (func, fu...
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...
#BBC_BASIC
BBC BASIC
Size% = 5 DIM array%(Size%-1,Size%-1)   i% = 1 j% = 1 FOR e% = 0 TO Size%^2-1 array%(i%-1,j%-1) = e% IF ((i% + j%) AND 1) = 0 THEN IF j% < Size% j% += 1 ELSE i% += 2 IF i% > 1 i% -= 1 ELSE IF i% < Size% i% += 1 ELSE j% += 2 IF...
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#Lua
Lua
function gcd(a, b) if b == 0 then return a end return gcd(b, a % b) end   function printArray(a) io.write('[') for i,v in pairs(a) do if i > 1 then io.write(', ') end io.write(v) end io.write(']') return nil end   function removeAt(a, i) lo...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
Manipulate[ Column[Flatten[ StringCases[ StringCases[ URLFetch[ "http://search.yahoo.com/search?p=" <> query <> "&b=" <> ToString@page], "<ol" ~~ ___ ~~ "</ol>"], "<a" ~~ Shortest[__] ~~ "class=\"yschttl spt\" href=\"" ~~ Shortest[url__] ~~ "\"" ~~ Shortest[__] ~~ ">" ~~ Sh...
http://rosettacode.org/wiki/Yahoo!_search_interface
Yahoo! search interface
Create a class for searching Yahoo! results. It must implement a Next Page method, and read URL, Title and Content from results.
#Nim
Nim
import httpclient, strutils, htmlparser, xmltree, strtabs const PageSize = 7 YahooURLPattern = "https://search.yahoo.com/search?fr=opensearch&b=$$#&pz=$#&p=".format(PageSize) type SearchResult = ref object url, title, content: string SearchInterface = ref object client: HttpClient urlPattern: string...
http://rosettacode.org/wiki/Zumkeller_numbers
Zumkeller numbers
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ...
#Visual_Basic_.NET
Visual Basic .NET
Module Module1 Function GetDivisors(n As Integer) As List(Of Integer) Dim divs As New List(Of Integer) From { 1, n } Dim i = 2 While i * i <= n If n Mod i = 0 Then Dim j = n \ i divs.Add(i) If i <> j Then ...
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Hoon
Hoon
  =+ big=(pow 5 (pow 4 (pow 3 2))) =+ digits=(lent (skip <big> |=(a/* ?:(=(a '.') & |)))) [digits (div big (pow 10 (sub digits 20))) (mod big (pow 10 20))]  
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#Icon_and_Unicon
Icon and Unicon
procedure main() x := 5^4^3^2 write("done with computation") x := string(x) write("5 ^ 4 ^ 3 ^ 2 has ",*x," digits") write("The first twenty digits are ",x[1+:20]) write("The last twenty digits are ",x[0-:20]) end
http://rosettacode.org/wiki/Zhang-Suen_thinning_algorithm
Zhang-Suen thinning algorithm
This is an algorithm used to thin a black and white i.e. one bit per pixel images. For example, with an input image of: ################# ############# ################## ################ #################...
#Tcl
Tcl
# -*- coding: utf-8 -*-   set data { 00000000000000000000000000000000 01111111110000000111111110000000 01110001111000001111001111000000 01110000111000001110000111000000 01110001111000001110000000000000 01111111110000001110000000000000 01110111100000001110000111000000 01110011110011101111001111011100 0111000111101110011...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Klingphix
Klingphix
include ..\Utilitys.tlhy   :listos  %i$ "" !i$ len [ get tostr $i$ chain !i$ ] for drop $i$ ;     :Zeckendorf %n !n  %i 0 !i %c 0 !c   [ $i 8 itob listos "11" find not ( [ ( $c ":" 9 tochar ) lprint tonum ? $c 1 + !c ] [drop] ) if $i 1 ...
http://rosettacode.org/wiki/Zeckendorf_number_representation
Zeckendorf number representation
Just as numbers can be represented in a positional notation as sums of multiples of the powers of ten (decimal) or two (binary); all the positive integers can be represented as the sum of one or zero times the distinct members of the Fibonacci series. Recall that the first six distinct Fibonacci numbers are: 1, 2, 3, ...
#Kotlin
Kotlin
// version 1.0.6   const val LIMIT = 46 // to stay within range of signed 32 bit integer val fibs = fibonacci(LIMIT)   fun fibonacci(n: Int): IntArray { if (n !in 2..LIMIT) throw IllegalArgumentException("n must be between 2 and $LIMIT") val fibs = IntArray(n) fibs[0] = 1 fibs[1] = 1 for (i in 2 un...
http://rosettacode.org/wiki/100_doors
100 doors
There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and  toggle  the door  (if the door is closed,  open it;   if it is open,  close it). The second time, only visit every 2nd door   (door #2, #4, #6, ...),   and toggle it. The third...
#COBOL
COBOL
IDENTIFICATION DIVISION. PROGRAM-ID. 100Doors.   DATA DIVISION. WORKING-STORAGE SECTION. 01 Current-n PIC 9(3). 01 StepSize PIC 9(3). 01 DoorTable. 02 Doors PIC 9(1) OCCURS 100 TIMES. 88 ClosedDoor VALUE ZERO. 01 ...
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,...
#Frink
Frink
  a = new array a@0 = 10 a@1 = 20 println[a@1]   b = [1, 2, 3]  
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Rust
Rust
extern crate num; use num::complex::Complex;   fn main() { // two valid forms of definition let a = Complex {re:-4.0, im: 5.0}; let b = Complex::new(1.0, 1.0);   println!(" a = {}", a); println!(" b = {}", b); println!(" a + b = {}", a + b); println!(" a * b = {}", a * b); pr...
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Scala
Scala
package org.rosettacode   package object ArithmeticComplex { val i = Complex(0, 1)   implicit def fromDouble(d: Double) = Complex(d) implicit def fromInt(i: Int) = Complex(i.toDouble) }   package ArithmeticComplex { case class Complex(real: Double = 0.0, imag: Double = 0.0) { def this(s: String) = ...
http://rosettacode.org/wiki/Arithmetic/Rational
Arithmetic/Rational
Task Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language. Example Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number). Fur...
#Tcl
Tcl
namespace eval rat {}   proc rat::new {args} { if {[llength $args] == 0} { set args {0} } lassign [split {*}$args] n d if {$d == 0} { error "divide by zero" } if {$d < 0} { set n [expr {-1 * $n}] set d [expr {abs($d)}] } return [normalize $n $d] }   proc r...
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#.D0.9C.D0.9A-61.2F52
МК-61/52
Сx ^ x^y С/П
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Nanoquery
Nanoquery
println 0^0
http://rosettacode.org/wiki/Zero_to_the_zero_power
Zero to the zero power
Some computer programming languages are not exactly consistent   (with other computer programming languages)   when   raising zero to the zeroth power:     00 Task Show the results of raising   zero   to the   zeroth   power. If your computer language objects to     0**0     or     0^0     at compile time, ...
#Neko
Neko
/** Zero to the zeroth power, in Neko */   var math_pow = $loader.loadprim("std@math_pow", 2)   $print(math_pow(0, 0), "\n")
http://rosettacode.org/wiki/Zebra_puzzle
Zebra puzzle
Zebra puzzle You are encouraged to solve this task according to the task description, using any language you may know. The Zebra puzzle, a.k.a. Einstein's Riddle, is a logic puzzle which is to be solved programmatically. It has several variants, one of them this:   There are five houses.   The English man lives ...
#C.23
C#
using System; using System.Collections.Generic; using System.Linq; using System.Text; using static System.Console;   public enum Colour { Red, Green, White, Yellow, Blue } public enum Nationality { Englishman, Swede, Dane, Norwegian,German } public enum Pet { Dog, Birds, Cats, Horse, Zebra } public enum Drink { Coffee,...
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#C.2B.2B
C++
#include <cassert> #include <cstdlib> #include <iostream> #include <stdexcept> #include <utility> #include <vector>   #include <libxml/parser.h> #include <libxml/tree.h> #include <libxml/xmlerror.h> #include <libxml/xmlstring.h> #include <libxml/xmlversion.h> #include <libxml/xpath.h>   #ifndef LIBXML_XPATH_ENABLED # ...
http://rosettacode.org/wiki/Yin_and_yang
Yin and yang
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu. Task   Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.   Generate and display the symbol for two different (small) sizes.
#BASIC
BASIC
pi=3.141592 s=.5   xp=320:yp=100:size=150 GOSUB DrawYY   xp=500:yp=40:size=50 GOSUB DrawYY   END   DrawYY: CIRCLE (xp,yp),size,,,,s CIRCLE (xp,yp+size/4),size/8,,,,s CIRCLE (xp,yp-size/4),size/8,,,,s CIRCLE (xp,yp+size/4),size/2,,.5*pi,1.5*pi,s CIRCLE (xp,yp-size/4),size/2,,1.5*pi,2*pi,s CIRCLE (xp,yp-size/...
http://rosettacode.org/wiki/Yin_and_yang
Yin and yang
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu. Task   Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.   Generate and display the symbol for two different (small) sizes.
#BCPL
BCPL
get "libhdr"   let circle(x, y, c, r) = (r*r) >= (x/2) * (x/2) + (y-c) * (y-c)   let pixel(x, y, r) = circle(x, y, -r/2, r/6) -> '#', circle(x, y, r/2, r/6) -> '.', circle(x, y, -r/2, r/2) -> '.', circle(x, y, r/2, r/2) -> '#', circle(x, y, 0, r) -> x<0 -> '.', '#', ' '   let yinyang(r) ...