task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Pascal%27s_triangle | Pascal's triangle | Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is either 1 or the sum of the two elemen... | #Haskell | Haskell | zapWith :: (a -> a -> a) -> [a] -> [a] -> [a]
zapWith f xs [] = xs
zapWith f [] ys = ys
zapWith f (x:xs) (y:ys) = f x y : zapWith f xs ys | Give a code snippet in #Haskell
Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is eith... | christopher/rosetta-code | |
http://rosettacode.org/wiki/I_before_E_except_after_C | I before E except after C | The phrase "I before E, except after C" is a
widely known mnemonic which is supposed to help when spelling English words.
Task
Using the word list from http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
check if the two sub-clauses of the phrase are plausible individually:
"I before E when not pre... | #Phix | Phix | -- demo\rosetta\IbeforeE.exw
with javascript_semantics
procedure show_plausibility(string msg, integer w, wo)
string no = iff(w<2*wo?" not":"")
printf(1, "%s (pro: %3d, anti: %3d) is%s plausible\n",{msg,w,wo,no})
end procedure
string text = join(unix_dict())
-- Note: my unixdict.txt begins with "10th" and ends... | Give a code snippet in #Phix
The phrase "I before E, except after C" is a
widely known mnemonic which is supposed to help when spelling English words.
Task
Using the word list from http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
check if the two sub-clauses of the phrase are plausible individually... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Apply_a_callback_to_an_array | Apply a callback to an array | Task
Take a combined set of elements and apply a function to each element.
| #Java | Java | public class ArrayCallback7 {
interface IntConsumer {
void run(int x);
}
interface IntToInt {
int run(int x);
}
static void forEach(int[] arr, IntConsumer consumer) {
for (int i : arr) {
consumer.run(i);
}
}
static void update(int[] arr, In... | Give a code snippet in #Java
Task
Take a combined set of elements and apply a function to each element.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/OpenGL | OpenGL |
Task
Display a smooth shaded triangle with OpenGL.
Triangle created using C example compiled with GCC 4.1.2 and freeglut3.
| #Delphi | Delphi |
program OpenGLTriangle;
{$APPTYPE CONSOLE}
uses
System.Classes,
Sample.App,
Winapi.OpenGL,
System.UITypes;
type
TTriangleApp = class(TApplication)
public
procedure Initialize; override;
procedure Update(const ADeltaTimeSec, ATotalTimeSec: Double); override;
procedure Shutdown; override;
... | Give a code snippet in #Delphi
Task
Display a smooth shaded triangle with OpenGL.
Triangle created using C example compiled with GCC 4.1.2 and freeglut3.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_HTML_table | Create an HTML table | Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers.
The... | #Objeck | Objeck |
class CreateTable {
function : Main(args : String[]) ~ Nil {
s := String->New();
s->Append("<table>");
s->Append("<thead align = \"right\">");
s->Append("<tr><th></th>");
td := "XYZ";
for(i:=0; i<3; i+=1;) {
s->Append("<td>");
s->Append(td->Get(i));
s->Append("</td>");
... | Give a code snippet in #Objeck
Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled wi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_prisoners | 100 prisoners |
The Problem
100 prisoners are individually numbered 1 to 100
A room having a cupboard of 100 opaque drawers numbered 1 to 100, that cannot be seen from outside.
Cards numbered 1 to 100 are placed randomly, one to a drawer, and the drawers all closed; at the start.
Prisoners start outside the room
They can decid... | #D | D | import std.array;
import std.random;
import std.range;
import std.stdio;
import std.traits;
bool playOptimal() {
auto secrets = iota(100).array.randomShuffle();
prisoner:
foreach (p; 0..100) {
auto choice = p;
foreach (_; 0..50) {
if (secrets[choice] == p) continue prisoner;
... | Give a code snippet in #D
The Problem
100 prisoners are individually numbered 1 to 100
A room having a cupboard of 100 opaque drawers numbered 1 to 100, that cannot be seen from outside.
Cards numbered 1 to 100 are placed randomly, one to a drawer, and the drawers all closed; at the start.
Prisoners start outsi... | 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... | #zkl | zkl | fcn zz(n){
grid := (0).pump(n,List, (0).pump(n,List).copy).copy();
ri := Ref(0);
foreach d in ([1..n*2]){
x:=(0).max(d - n); y:=(n - 1).min(d - 1);
(0).pump(d.min(n*2 - d),Void,'wrap(it){
grid[if(d%2)y-it else x+it][if(d%2)x+it else y-it] = ri.inc();
});
}
grid.pump(String,'wra... | Give a code snippet in #zkl
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 encod... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Tcl | Tcl | package require Tcl 8.5
# Bitwise test is the most efficient
proc tcl::mathfunc::isOdd x { expr {$x & 1} }
proc tcl::mathfunc::isEven x { expr {!($x & 1)} }
puts " # O E"
puts 24:[expr isOdd(24)],[expr isEven(24)]
puts 49:[expr isOdd(49)],[expr isEven(49)] | Give a code snippet in #Tcl
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_shuffle | Perfect shuffle | A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ K♠→7♠ J♠ 8♠ Q♠ 9♠ K♠
When you ... | #Nim | Nim | import sequtils, strutils
proc newValList(size: Positive): seq[int] =
if (size and 1) != 0:
raise newException(ValueError, "size must be even.")
result = toSeq(1..size)
func shuffled(list: seq[int]): seq[int] =
result.setLen(list.len)
let half = list.len div 2
for i in 0..<half:
result[2 * i] = ... | Give a code snippet in #Nim
A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ K♠→... | 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... | #BASIC | BASIC | FOR I = 2 TO 8 STEP 2 : PRINT I; ", "; : NEXT I : PRINT "WHO DO WE APPRECIATE?" | Give a code snippet in #BASIC
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/Inc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Phrase_reversals | Phrase reversals | Task
Given a string of space separated words containing the following phrase:
rosetta code phrase reversal
Reverse the characters of the string.
Reverse the characters of each individual word in the string, maintaining original word order within the string.
Reverse the order of each word of the string, maintaini... | #Oforth | Oforth | "rosetta code phrase reversal" reverse println
"rosetta code phrase reversal" words map(#reverse) unwords println
"rosetta code phrase reversal" words reverse unwords println | Give a code snippet in #Oforth
Task
Given a string of space separated words containing the following phrase:
rosetta code phrase reversal
Reverse the characters of the string.
Reverse the characters of each individual word in the string, maintaining original word order within the string.
Reverse the order of ea... | 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 ... | #Ring | Ring |
give n
x = fib(n)
see n + " Fibonacci is : " + x
func fib nr if nr = 0 return 0 ok
if nr = 1 return 1 ok
if nr > 1 return fib(nr-1) + fib(nr-2) ok
| Give a code snippet in #Ring
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nested_function | Nested function | In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two nested functions that prints t... | #M2000_Interpreter | M2000 Interpreter |
Module Checkit {
Make_List(". ")
Sub Make_List(Separator$)
Local Counter=0
Make_Item("First")
Make_Item("Second")
Make_Item("Third")
End Sub
Sub Make_Item(Item_Name$)
Counter++
Print Str$(Counter,"")+Separator$+Item_Name$
... | Give a code snippet in #M2000_Interpreter
In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_a_function | Call a function | Task
Demonstrate the different syntax and semantics provided for calling a function.
This may include:
Calling a function that requires no arguments
Calling a function with a fixed number of arguments
Calling a function with optional arguments
Calling a function with a variable number of arguments
C... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | f[] | Give a code snippet in #Mathematica_.2F_Wolfram_Language
Task
Demonstrate the different syntax and semantics provided for calling a function.
This may include:
Calling a function that requires no arguments
Calling a function with a fixed number of arguments
Calling a function with optional arguments
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Diversity_prediction_theorem | Diversity prediction theorem | The wisdom of the crowd is the collective opinion of a group of individuals rather than that of a single expert.
Wisdom-of-the-crowds research routinely attributes the superiority of crowd averages over individual judgments to the elimination of individual noise, an explanation that assumes independence of the i... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | package main
import "fmt"
func averageSquareDiff(f float64, preds []float64) (av float64) {
for _, pred := range preds {
av += (pred - f) * (pred - f)
}
av /= float64(len(preds))
return
}
func diversityTheorem(truth float64, preds []float64) (float64, float64, float64) {
av := 0.0
... | Give a code snippet in #F.C5.8Drmul.C3.A6
The wisdom of the crowd is the collective opinion of a group of individuals rather than that of a single expert.
Wisdom-of-the-crowds research routinely attributes the superiority of crowd averages over individual judgments to the elimination of individual noise, an exp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leonardo_numbers | Leonardo numbers |
Leonardo numbers are also known as the Leonardo series.
The Leonardo numbers are a sequence of numbers defined by:
L(0) = 1 [1st equation]
L(1) = 1 [2nd equation]
L(n) = L(n-1) + L(n-2) + 1 ... | #VBA | VBA |
Option Explicit
Private Sub LeonardoNumbers()
Dim L, MyString As String
Debug.Print "First 25 Leonardo numbers :"
L = Leo_Numbers(25, 1, 1, 1)
MyString = Join(L, "; ")
Debug.Print MyString
Debug.Print "First 25 Leonardo numbers from 0, 1 with add number = 0"
L = Leo_Numbers(25, 0, 1, 0)
... | Give a code snippet in #VBA
Leonardo numbers are also known as the Leonardo series.
The Leonardo numbers are a sequence of numbers defined by:
L(0) = 1 [1st equation]
L(1) = 1 [2nd equation]
L(n) = L... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Permutations/Derangements | Permutations/Derangements | A derangement is a permutation of the order of distinct items in which no item appears in its original place.
For example, the only two derangements of the three items (0, 1, 2) are (1, 2, 0), and (2, 0, 1).
The number of derangements of n distinct items is known as the subfactorial of n, sometimes written as !n.
The... | #Clojure | Clojure | (ns derangements.core
(:require [clojure.set :as s]))
(defn subfactorial [n]
(case n
0 1
1 0
(* (dec n) (+ (subfactorial (dec n)) (subfactorial (- n 2))))))
(defn no-fixed-point
"f : A -> B must be a biyective function written as a hash-map, returns
all g : A -> B such that (f(a) = b) => not(g(a... | Give a code snippet in #Clojure
A derangement is a permutation of the order of distinct items in which no item appears in its original place.
For example, the only two derangements of the three items (0, 1, 2) are (1, 2, 0), and (2, 0, 1).
The number of derangements of n distinct items is known as the subfactorial o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mouse_position | Mouse position | Task
Get the current location of the mouse cursor relative to the active window.
Please specify if the window may be externally created.
| #Emacs_Lisp | Emacs Lisp | (mouse-pixel-position)
;; => (FRAME . (X . Y)) | Give a code snippet in #Emacs_Lisp
Task
Get the current location of the mouse cursor relative to the active window.
Please specify if the window may be externally created.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Death_Star | Death Star |
Task
Display a region that consists of a large sphere with part of a smaller sphere removed from it as a result of geometric subtraction.
(This will basically produce a shape like a "death star".)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
| #Java | Java | import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.geometry.Point3D;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.shape.MeshView;
import javafx.scene.shape.TriangleMesh;
import javafx.... | Give a code snippet in #Java
Task
Display a region that consists of a large sphere with part of a smaller sphere removed from it as a result of geometric subtraction.
(This will basically produce a shape like a "death star".)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
write language nam... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_puzzle | Sum and product puzzle | Task[edit]
Solve the "Impossible Puzzle":
X and Y are two different whole numbers greater than 1. Their sum is no greater than 100, and Y is greater than X. S and P are two mathematicians (and consequently perfect logicians); S knows the sum X+Y and P knows the product X*Y. Both S and P know all the information in th... | #C.23 | C# | using System;
using System.Linq;
using System.Collections.Generic;
public class Program
{
public static void Main()
{
const int maxSum = 100;
var pairs = (
from X in 2.To(maxSum / 2 - 1)
from Y in (X + 1).To(maxSum - 2).TakeWhile(y => X + y <= maxSum)
select... | Give a code snippet in #C.23
Task[edit]
Solve the "Impossible Puzzle":
X and Y are two different whole numbers greater than 1. Their sum is no greater than 100, and Y is greater than X. S and P are two mathematicians (and consequently perfect logicians); S knows the sum X+Y and P knows the product X*Y. Both S and P ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #Wart | Wart | def (best f seq)
if seq
ret winner car.seq
each elem cdr.seq
if (f elem winner)
winner <- elem
def (max ... args)
(best (>) args) | Give a code snippet in #Wart
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pascal%27s_triangle | Pascal's triangle | Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is either 1 or the sum of the two elemen... | #Groovy | Groovy | def pascal
pascal = { n -> (n <= 1) ? [1] : [[0] + pascal(n - 1), pascal(n - 1) + [0]].transpose().collect { it.sum() } } | Give a code snippet in #Groovy
Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is eithe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/HTTP | HTTP | Task
Access and print a URL's content (the located resource) to the console.
There is a separate task for HTTPS Requests.
| #Dragon | Dragon | select "http"
select "std"
http("http://www.rosettacode.org", ::echo)
| Give a code snippet in #Dragon
Task
Access and print a URL's content (the located resource) to the console.
There is a separate task for HTTPS Requests.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list | Search a list | Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that has multiple occurrences in ... | #Factor | Factor | : find-index ( seq elt -- i )
'[ _ = ] find drop [ "Not found" throw ] unless* ; inline
: find-last-index ( seq elt -- i )
'[ _ = ] find-last drop [ "Not found" throw ] unless* ; inline | Give a code snippet in #Factor
Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Video_display_modes | Video display modes | The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| #Julia | Julia |
if Base.Sys.islinux()
run(`xrandr -s 640x480`)
sleep(3)
run(`xrandr -s 1280x960`)
else # windows
run(`mode CON: COLS=40 LINES=100`)
sleep(3)
run(`mode CON: COLS=100 LINES=50`)
end
| Give a code snippet in #Julia
The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Smarandache_prime-digital_sequence | Smarandache prime-digital sequence | The Smarandache prime-digital sequence (SPDS for brevity) is the sequence of primes whose digits are themselves prime.
For example 257 is an element of this sequence because it is prime itself and its digits: 2, 5 and 7 are also prime.
Task
Show the first 25 SPDS primes.
Show the hundredth SPDS prime.
See also
... | #REXX | REXX | /*REXX program lists a sequence of SPDS (Smarandache prime-digital sequence) primes.*/
parse arg n q /*get optional number of primes to find*/
if n=='' | n=="," then n= 25 /*Not specified? Then use the default.*/
if q='' then q= 100 1000 ... | Give a code snippet in #REXX
The Smarandache prime-digital sequence (SPDS for brevity) is the sequence of primes whose digits are themselves prime.
For example 257 is an element of this sequence because it is prime itself and its digits: 2, 5 and 7 are also prime.
Task
Show the first 25 SPDS primes.
Show the hundr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Environment_variables | Environment variables | Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| #Forth | Forth | s" HOME" getenv type | Give a code snippet in #Forth
Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Kernighans_large_earthquake_problem | Kernighans large earthquake problem | Brian Kernighan, in a lecture at the University of Nottingham, described a problem on which this task is based.
Problem
You are given a a data file of thousands of lines; each of three `whitespace` separated fields: a date, a one word name and the magnitude of the event.
Example lines from the file would be lines li... | #BASIC256 | BASIC256 |
f = freefile
filename$ = "data.txt"
open f, filename$
dim tok$(1)
while not eof(f)
tok$[] = readline(f)
if (right(tok$[], 4)) > 6 then print tok$[]
end while
close f
end
| Give a code snippet in #BASIC256
Brian Kernighan, in a lecture at the University of Nottingham, described a problem on which this task is based.
Problem
You are given a a data file of thousands of lines; each of three `whitespace` separated fields: a date, a one word name and the magnitude of the event.
Example lin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #HicEst | HicEst | REAL :: n=8, set(n), sum=0, sum2=0
set = (2,4,4,4,5,5,7,9)
DO k = 1, n
WRITE() 'Adding ' // set(k) // 'stdev = ' // stdev(set(k))
ENDDO
END ! end of "main"
FUNCTION stdev(x)
USE : sum, sum2, k
sum = sum + x
sum2 = sum2 + x*x
stdev = ( sum2/k - (sum/k)^2) ^ 0.5
END | Give a code snippet in #HicEst
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the func... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_factors | Count in factors | Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it would be shown as
2
×
3
{\di... | #Euphoria | Euphoria | function factorize(integer n)
sequence result
integer k
if n = 1 then
return {1}
else
k = 2
result = {}
while n > 1 do
while remainder(n, k) = 0 do
result &= k
n /= k
end while
k += 1
end while
... | Give a code snippet in #Euphoria
Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it wo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Infinity | Infinity | Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, return the largest possible po... | #Io | Io | inf := 1/0 | Give a code snippet in #Io
Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/French_Republican_calendar | French Republican calendar | Write a program to convert dates between the Gregorian calendar and the French Republican calendar.
The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of... | #Nim | Nim |
import strformat, strscans, strutils, times
const
RcMonths = ["Vendémiaire", "Brumaire", "Frimaire", "Nivôse", "Pluviôse", "Ventôse",
"Germinal", "Floréal", "Prairial", "Messidor", "Thermidor", "Fructidor"]
SansCulottides = ["Fête de la vertu", "Fête du génie", "Fête du travail",
... | Give a code snippet in #Nim
Write a program to convert dates between the Gregorian calendar and the French Republican calendar.
The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_prisoners | 100 prisoners |
The Problem
100 prisoners are individually numbered 1 to 100
A room having a cupboard of 100 opaque drawers numbered 1 to 100, that cannot be seen from outside.
Cards numbered 1 to 100 are placed randomly, one to a drawer, and the drawers all closed; at the start.
Prisoners start outside the room
They can decid... | #Cowgol | Cowgol | include "cowgol.coh";
include "argv.coh";
# Parameters
const Drawers := 100; # Amount of drawers (and prisoners)
const Attempts := 50; # Amount of attempts a prisoner may make
const Simulations := 2000; # Amount of simulations to run
typedef NSim is int(0, Simulations);
# Random number generator
reco... | Give a code snippet in #Cowgol
The Problem
100 prisoners are individually numbered 1 to 100
A room having a cupboard of 100 opaque drawers numbered 1 to 100, that cannot be seen from outside.
Cards numbered 1 to 100 are placed randomly, one to a drawer, and the drawers all closed; at the start.
Prisoners start ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knight%27s_tour | Knight's tour |
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; that is, the knight need not e... | #Clojure | Clojure |
(defn isin? [x li]
(not= [] (filter #(= x %) li)))
(defn options [movements pmoves n]
(let [x (first (last movements)) y (second (last movements))
op (vec (map #(vector (+ x (first %)) (+ y (second %))) pmoves))
vop (filter #(and (>= (first %) 0) (>= (last %) 0)) op)
vop1 (filter #(and (... | Give a code snippet in #Clojure
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conway%27s_Game_of_Life | Conway's Game of Life | The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, in an m-by-m (or m×m) sq... | #Elixir | Elixir | defmodule Conway do
def game_of_life(name, size, generations, initial_life\\nil) do
board = seed(size, initial_life)
print_board(board, name, size, 0)
reason = generate(name, size, generations, board, 1)
case reason do
:all_dead -> "no more life."
:static -> "no movement"
_ ... | Give a code snippet in #Elixir
The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
... | #Prolog | Prolog | rosetta_sleep(Time) :-
writeln('Sleeping...'),
sleep(Time),
writeln('Awake!').
| Give a code snippet in #Prolog
Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main threa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Factor | Factor | USE: io.directories
"output.txt" "/output.txt" [ touch-file ] bi@
"docs" "/docs" [ make-directory ] bi@ | Give a code snippet in #Factor
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| 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
... | #Yabasic | Yabasic |
sub shuffle(a())
n = arraysize(a(),1)
m = arraysize(a(),1)*2
for k = 1 to m
i = int(Ran(n))
j = int(Ran(n))
tmp = a(i) //swap a(i), a(j)
a(i) = a(j)
a(j) = tmp
next k
end sub
sub inorder(a())
n = arraysize(a(),1)
for i = 0 to n-2
if a(... | Give a code snippet in #Yabasic
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pick_random_element | Pick random element | Demonstrate how to pick a random element from a list.
| #VBA | VBA |
Option Explicit
Sub Main_Pick_Random_Element()
Debug.Print Pick_Random_Element(Array(1, 2, 3, 4, 5, #11/24/2017#, "azerty"))
End Sub
Function Pick_Random_Element(myArray)
Randomize Timer
Pick_Random_Element = myArray(Int((Rnd * (UBound(myArray) - LBound(myArray) + 1) + LBound(myArray))))
End Function
... | Give a code snippet in #VBA
Demonstrate how to pick a random element from a list.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Solve_a_Numbrix_puzzle | Solve a Numbrix puzzle | Numbrix puzzles are similar to Hidato.
The most important difference is that it is only possible to move 1 node left, right, up, or down (sometimes referred to as the Von Neumann neighborhood).
Published puzzles also tend not to have holes in the grid and may not always indicate the end node.
Two examples follow:
Exam... | #SystemVerilog | SystemVerilog |
//////////////////////////////////////////////////////////////////////////////
/// NumbrixSolver ///
/// Solve the puzzle, by using system verilog randomization engine ///
//////////////////////////////////////////////////////////////////////////////
... | Give a code snippet in #SystemVerilog
Numbrix puzzles are similar to Hidato.
The most important difference is that it is only possible to move 1 node left, right, up, or down (sometimes referred to as the Von Neumann neighborhood).
Published puzzles also tend not to have holes in the grid and may not always indicate t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_sphere | Draw a sphere | Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a Deathstar
| #Ada | Ada | with Glib; use Glib;
with Cairo; use Cairo;
with Cairo.Png; use Cairo.Png;
with Cairo.Pattern; use Cairo.Pattern;
with Cairo.Image_Surface; use Cairo.Image_Surface;
with Ada.Numerics;
procedure Sphere is
subtype Dub is Glib.Gdouble;
Surface : Cairo_Surface;
C... | Give a code snippet in #Ada
Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a Deat... | 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... | #Wart | Wart | def (gens n l)
prn l
repeat n
zap! gen l
prn l
def (gen l)
with (a nil b nil c l.0)
collect nil # won't insert paren without second token
each x cdr.l
shift! a b c x
yield (next a b c)
yield (next b c nil)
def (next a b c) # next state of b given neighbors a and c
... | Give a code snippet in #Wart
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_search | Binary search | A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret number, and will only tell the p... | #Liberty_BASIC | Liberty BASIC |
dim theArray(100)
for i = 1 to 100
theArray(i) = i
next i
print binarySearch(80,30,90)
wait
FUNCTION binarySearch(val, lo, hi)
IF hi < lo THEN
binarySearch = 0
ELSE
middle = int((hi + lo) / 2):print middle
if val < theArray(middle) then binarySearch = binarySearch(val, lo, middle-1)
if val... | Give a code snippet in #Liberty_BASIC
A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Objeck | Objeck |
use Collection;
class Mode {
function : Main(args : String[]) ~ Nil {
Print(Mode([1, 3, 6, 6, 6, 6, 7, 7, 12, 12, 17]));
Print(Mode([1, 2, 4, 4, 1]));
}
function : Mode(coll : Int[]) ~ IntVector {
seen := IntMap->New();
max := 0;
maxElems := IntVector->New();
each(i : coll) {
... | Give a code snippet in #Objeck
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/Hello_world/Standard_error | Hello world/Standard error | Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out".
The error messages print to ... | #sed | sed | #n
1 {
s/.*/Goodbye, World!/w /dev/stderr
} | Give a code snippet in #sed
Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out".
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #MAXScript | MAXScript | inFile = openFile "input.txt"
outFile = createFile "output.txt"
while not EOF inFile do
(
format "%" (readLine inFile) to:outFile
)
close inFile
close outFile | Give a code snippet in #MAXScript
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a fi... | 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... | #AWK | AWK |
# syntax: GAWK -f BENFORDS_LAW.AWK
BEGIN {
n = 1000
for (i=1; i<=n; i++) {
arr[substr(fibonacci(i),1,1)]++
}
print("digit expected observed deviation")
for (i=1; i<=9; i++) {
expected = log10(i+1) - log10(i)
actual = arr[i] / n
deviation = expected - actual
printf... | Give a code snippet in #AWK
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-di... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #REXX | REXX | /*REXX program demonstrates four queueing operations: push, pop, empty, query. */
say '══════════════════════════════════ Pushing five values to the stack.'
do j=1 for 4 /*a DO loop to PUSH four values. */
call push j * 10 /*PUSH (aka:... | Give a code snippet in #REXX
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_Computer/Zero | Execute Computer/Zero | Execute Computer/Zero is an implementation of Computer/zero Assembly.
Other implementations of Computer/zero Assembly.
Task
Create a Computer/zero Assembly emulator. You may consider this webpage as a reference implementation. Output the results of the sample programs "2+2" and "7*8" found there.
The virtual machi... | #Z80_Assembly | Z80 Assembly | org &1000
PrintChar equ &BB5A
;reg usage:
;DE = VM'S Program Counter
;IXL = VM's Accumulator
main:
ld ixl,0
ld de,Computer_Zero_RAM_2_plus_2
call Computer_Zero_VM
ld a,ixl
call ShowHex ;output to Amstrad CPC's screen
call NewLine
ld ixl,0
ld de,Computer_Zero_RAM_7x8
call Computer_Zero_VM
ld a,ixl
jp Show... | Give a code snippet in #Z80_Assembly
Execute Computer/Zero is an implementation of Computer/zero Assembly.
Other implementations of Computer/zero Assembly.
Task
Create a Computer/zero Assembly emulator. You may consider this webpage as a reference implementation. Output the results of the sample programs "2+2" and "7... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" /... | #OCaml | OCaml | # #directory "+xml-light" (* or maybe "+site-lib/xml-light" *) ;;
# #load "xml-light.cma" ;;
# let x = Xml.parse_string "
<Students>
<Student Name='April' Gender='F' DateOfBirth='1989-01-02' />
<Student Name='Bob' Gender='M' DateOfBirth='1990-03-04' />
<Student Name='Chad' Gender='M' DateOfBirth='1991... | Give a code snippet in #OCaml
Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender=... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_interpolation_(included) | String interpolation (included) |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #C.23 | C# | class Program
{
static void Main()
{
string extra = "little";
string formatted = $"Mary had a {extra} lamb.";
System.Console.WriteLine(formatted);
}
} | Give a code snippet in #C.23
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #C.2B.2B | C++ |
#include <iostream>
#include <stack>
#include <vector>
struct DataFrame {
int sum;
std::vector<int> coins;
std::vector<int> avail_coins;
};
int main() {
std::stack<DataFrame> s;
s.push({ 100, {}, { 25, 10, 5, 1 } });
int ways = 0;
while (!s.empty()) {
DataFrame top = s.top();
s.pop();
if... | Give a code snippet in #C.2B.2B
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/Knight%27s_tour | Knight's tour |
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; that is, the knight need not e... | #Sidef | Sidef | var board = []
var I = 8
var J = 8
var F = (I*J > 99 ? '%3d' : '%2d')
var (i, j) = (I.irand, J.irand)
func from_algebraic(square) {
if (var match = square.match(/^([a-z])([0-9])\z/)) {
return(I - Num(match[1]), match[0].ord - 'a'.ord)
}
die "Invalid block square: #{square}"
}
func possible... | Give a code snippet in #Sidef
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed";... | 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... | #Rascal | Rascal | 0 (0,0), 1 (0,1), 3 (0,2)
2 (1,0), 4 (1,1), 6 (1,2)
5 (2,0), 7 (2,1), 8 (2,2) | Give a code snippet in #Rascal
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 en... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Julia_set | Julia set |
Task
Generate and draw a Julia set.
Related tasks
Mandelbrot Set
| #Sidef | Sidef | require('Imager')
var (w, h) = (640, 480)
var img = %s'Imager'.new(xsize => w, ysize => h, channels => 3)
var maxIter = 50
var c = Complex(-0.388, 0.613)
var color = %s'Imager::Color'.new('#000000')
for x,y in (^w ~X ^h) {
var i = maxIter
var z = Complex((x - w/2) / w * 3, (y - h/2) / h * 2)
while (... | Give a code snippet in #Sidef
Task
Generate and draw a Julia set.
Related tasks
Mandelbrot Set
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_function | Roots of a function | Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| #AutoHotkey | AutoHotkey | MsgBox % roots("poly", -0.99, 2, 0.1, 1.0e-5)
MsgBox % roots("poly", -1, 3, 0.1, 1.0e-5)
roots(f,x1,x2,step,tol) { ; search for roots in intervals of length "step", within tolerance "tol"
x := x1, y := %f%(x), s := (y>0)-(y<0)
Loop % ceil((x2-x1)/step) {
x += step, y := %f%(x), t := (y>0)-(y<0)
If (... | Give a code snippet in #AutoHotkey
Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #ANSI_Standard_BASIC | ANSI Standard BASIC | 100 DECLARE EXTERNAL SUB sumdiff
110 !
120 CALL sumdiff(5, 3, sum, diff)
130 PRINT "Sum is "; sum
140 PRINT "Difference is "; diff
150 END
160 !
170 EXTERNAL SUB sumdiff(a, b, c, d)
180 LET c = a + b
190 LET d = a - b
200 END SUB | Give a code snippet in #ANSI_Standard_BASIC
Task
Show how to return more than one value from a function.
| 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... | #Fantom | Fantom |
class FirstClassFns
{
static |Obj -> Obj| compose (|Obj -> Obj| fn1, |Obj -> Obj| fn2)
{
return |Obj x -> Obj| { fn2 (fn1 (x)) }
}
public static Void main ()
{
cube := |Float a -> Float| { a * a * a }
cbrt := |Float a -> Float| { a.pow(1/3f) }
|Float->Float|[] fns := [Float#sin.func, Fl... | Give a code snippet in #Fantom
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/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... | #SenseTalk | SenseTalk | put ("apple", "orange", "pear", "banana", "aubergine") into fruits
put the number of items in fruits | Give a code snippet in #SenseTalk
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 f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Multiple | Inheritance/Multiple | Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePhone, then write a class Camer... | #Fantom | Fantom | // a regular class
class Camera
{
Str cameraMsg ()
{
"camera"
}
}
// a mixin can only contain methods
mixin MobilePhone
{
Str mobileMsg ()
{
"mobile phone"
}
}
// class inherits from Camera, and mixes in the methods from MobilePhone
class CameraPhone : Camera, MobilePhone
{
}
class Main
{
pu... | Give a code snippet in #Fantom
Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobileP... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_length | String length | Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme containing combining characters.
F... | #Bracmat | Bracmat | (ByteLength=
length
. @(!arg:? [?length)
& !length
);
out$ByteLength$𝔘𝔫𝔦𝔠𝔬𝔡𝔢 | Give a code snippet in #Bracmat
Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Plot_coordinate_pairs | Plot coordinate pairs | Task
Plot a function represented as x, y numerical arrays.
Post the resulting image for the following input arrays (taken from Python's Example section on Time a function):
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | Dim As Integer i, x(9), y(9)
For i = 0 To 9
x(i) = i
Next i
y(0) = 2.7
y(1) = 2.8
y(2) = 31.4
y(3) = 38.1
y(4) = 58.0
y(5) = 76.2
y(6) = 100.5
y(7) = 130.0
y(8) = 149.3
y(9) = 180.0
Locate 22, 4
For i = 0 To 9
Locate 22, ((i * 4) + 2) : Print i
Next i
For i = 0 To 20 Step 2
Locate (21 - i), 0 : Print ... | Give a code snippet in #F.C5.8Drmul.C3.A6
Task
Plot a function represented as x, y numerical arrays.
Post the resulting image for the following input arrays (taken from Python's Example section on Time a function):
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
y = {2.7, 2.8,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Natural_sorting | Natural sorting |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <wchar.h>
#include <wctype.h>
#include <string.h>
#include <locale.h>
typedef struct wstr {
wchar_t *s;
int n, alloc;
} wstr;
#define w_del(w) { free(w->s); free(w); }
#define forchars(i, c, w) for(i = 0, c = w->s[0]; i < w->n && c; c = w->s[++i])
wstr *w_new()
{
w... | Give a code snippet in #C
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_digits_of_an_integer | Sum digits of an integer | Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| #C.2B.2B | C++ | #include <iostream>
#include <cmath>
int SumDigits(const unsigned long long int digits, const int BASE = 10) {
int sum = 0;
unsigned long long int x = digits;
for (int i = log(digits)/log(BASE); i>0; i--){
const double z = std::pow(BASE,i);
const unsigned long long int t = x/z;
sum += t;
x ... | Give a code snippet in #C.2B.2B
Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Power_set | Power set | A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or pow... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | # Built-in
Combinations([1, 2, 3]);
# [ [ ], [ 1 ], [ 1, 2 ], [ 1, 2, 3 ], [ 1, 3 ], [ 2 ], [ 2, 3 ], [ 3 ] ]
# Note that it handles duplicates
Combinations([1, 2, 3, 1]);
# [ [ ], [ 1 ], [ 1, 1 ], [ 1, 1, 2 ], [ 1, 1, 2, 3 ], [ 1, 1, 3 ], [ 1, 2 ], [ 1, 2, 3 ], [ 1, 3 ], ... | Give a code snippet in #F.C5.8Drmul.C3.A6
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ign... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Haskell | Haskell | import qualified Data.Map as M
type NodeID = Maybe Rational
data Node a = Node
{vNode :: a,
pNode, nNode :: NodeID}
type DLList a = M.Map Rational (Node a)
empty = M.empty
singleton a = M.singleton 0 $ Node a Nothing Nothing
fcons :: a -> DLList a -> DLList a
fcons a list | M.null list = singleton a
... | Give a code snippet in #Haskell
Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data ty... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string | Tokenize a string | Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks related to string operations:
Me... | #Action.21 | Action! | SET EndProg=* | Give a code snippet in #Action.21
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vogel%27s_approximation_method | Vogel's approximation method | Vogel's Approximation Method (VAM) is a technique for finding a good initial feasible solution to an allocation problem.
The powers that be have identified 5 tasks that need to be solved urgently. Being imaginative chaps, they have called them “A”, “B”, “C”, “D”, and “E”. They estimate that:
A will require 30 hours ... | #Sidef | Sidef | var costs = :(
W => :(A => 16, B => 16, C => 13, D => 22, E => 17),
X => :(A => 14, B => 14, C => 13, D => 19, E => 15),
Y => :(A => 19, B => 19, C => 20, D => 23, E => 50),
Z => :(A => 50, B => 12, C => 50, D => 15, E => 11)
)
var demand = :(A => 30, B => 20, C => 70, D => 30, E => 60)
var supply = :... | Give a code snippet in #Sidef
Vogel's Approximation Method (VAM) is a technique for finding a good initial feasible solution to an allocation problem.
The powers that be have identified 5 tasks that need to be solved urgently. Being imaginative chaps, they have called them “A”, “B”, “C”, “D”, and “E”. They estimate t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_termination | Program termination |
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks... | #SSEM | SSEM | 00000000000000110000000000000000 Test
00000000000001110000000000000000 Stop | Give a code snippet in #SSEM
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Maze_generation | Maze generation |
This page uses content from Wikipedia. The original article was at Maze generation algorithm. 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
Generate and show a maze, using the simple Depth... | #FreeBASIC | FreeBASIC | ' version 04-12-2016
' compile with: fbc -s console
' when generating a big maze it's possible to run out of stack space
' increase stack with the -t xxxx (xxxx is the amount you want in Kbytes)
ReDim Shared As String d() ' directions
ReDim Shared As ULong c() ' cell's
Sub cell(x As ULong, y As ULong, s As ULong)
... | Give a code snippet in #FreeBASIC
This page uses content from Wikipedia. The original article was at Maze generation algorithm. 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
Generate and ... | 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 ... | #C.23 | C# | static double multiply(double a, double b)
{
return a * b;
} | Give a code snippet in #C.23
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 f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping | Tokenize a string with escaping | Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for splitting:
The fields that were s... | #OCaml | OCaml | let split_with_escaping ~esc ~sep s =
let len = String.length s in
let buf = Buffer.create 16 in
let rec loop i =
if i = len then [Buffer.contents buf]
else if s.[i] = esc && i + 1 < len then begin
Buffer.add_char buf s.[i + 1];
loop (i + 2)
end else if s.[i] = sep then begin
let s =... | Give a code snippet in #OCaml
Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for spli... | 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... | #Oz | Oz | declare
proc {Knapsack Sol}
solution(panacea:P = {FD.decl}
ichor: I = {FD.decl}
gold: G = {FD.decl} ) = Sol
in
{Show 0#Sol}
3 * P + 2 * I + 20 * G =<: 250 {Show 1#Sol}
25 * P + 15 * I + 2 * G =<: 250 {Show 2#Sol}
... | Give a code snippet in #Oz
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 '... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lucas-Lehmer_test | Lucas-Lehmer test | Lucas-Lehmer Test:
for
p
{\displaystyle p}
an odd prime, the Mersenne number
2
p
−
1
{\displaystyle 2^{p}-1}
is prime if and only if
2
p
−
1
{\displaystyle 2^{p}-1}
divides
S
(
p
−
1
)
{\displaystyle S(p-1)}
where
S
(
n
+
1
)
=
(
S
(
n
)
)
2
−
2
{\displaystyle S(n+1)=(... | #D | D | import std.stdio, std.math, std.bigint;
bool isPrime(in uint p) pure nothrow @safe @nogc {
if (p < 2 || p % 2 == 0)
return p == 2;
foreach (immutable i; 3 .. cast(uint)real(p).sqrt + 1)
if (p % i == 0)
return false;
return true;
}
bool isMersennePrime(in uint p) pure nothrow ... | Give a code snippet in #D
Lucas-Lehmer Test:
for
p
{\displaystyle p}
an odd prime, the Mersenne number
2
p
−
1
{\displaystyle 2^{p}-1}
is prime if and only if
2
p
−
1
{\displaystyle 2^{p}-1}
divides
S
(
p
−
1
)
{\displaystyle S(p-1)}
where
S
(
n
+
1
)
=
(
S
(
n
)
)
2
−
... | 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... | #VAX_Assembly | VAX Assembly | 0000 0000 1 .entry main,0
50 D4 0002 2 clrf r0 ;init to 0.0
0004 3 loop:
01 0004 4 nop ;do nothing
FFF9 50 0A 3E 4F 0005 5 acbf #112.0, ... | Give a code snippet in #VAX_Assembly
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
Lo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Preserve_screen | Terminal control/Preserve screen |
Task
Clear the screen, output something on the display, and then restore the screen to the preserved state that it was in before the task was carried out.
There is no requirement to change the font or kerning in this task, however character decorations and attributes are expected to be preserved. If the implement... | #Action.21 | Action! | PROC Wait(BYTE frames)
BYTE RTCLOK=$14
frames==+RTCLOK
WHILE frames#RTCLOK DO OD
RETURN
PROC Main()
INT size=[960]
BYTE ARRAY buffer(size)
BYTE POINTER ptr
Graphics(0)
Position(2,10)
Print("This is the original screen content.")
Wait(200)
ptr=PeekC(88)
MoveBlock(buffer,ptr,size) ;copy scre... | Give a code snippet in #Action.21
Task
Clear the screen, output something on the display, and then restore the screen to the preserved state that it was in before the task was carried out.
There is no requirement to change the font or kerning in this task, however character decorations and attributes are expected ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Polynomial_regression | Polynomial regression | Find an approximating polynomial of known degree for a given data.
Example:
For input data:
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321};
The approximating polynomial is:
3 x2 + 2 x + 1
Here, the polynomial's coefficients are (3, 2, 1).
This task is i... | #PowerShell | PowerShell |
function qr([double[][]]$A) {
$m,$n = $A.count, $A[0].count
$pm,$pn = ($m-1), ($n-1)
[double[][]]$Q = 0..($m-1) | foreach{$row = @(0) * $m; $row[$_] = 1; ,$row}
[double[][]]$R = $A | foreach{$row = $_; ,@(0..$pn | foreach{$row[$_]})}
foreach ($h in 0..$pn) {
[double[]]$u = $R[$h..$pm] | ... | Give a code snippet in #PowerShell
Find an approximating polynomial of known degree for a given data.
Example:
For input data:
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
y = {1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321};
The approximating polynomial is:
3 x2 + 2 x + 1
Here, the polynomial's coeffic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Retrieve_and_search_chat_history | Retrieve and search chat history | Task
Summary: Find and print the mentions of a given string in the recent chat logs from a chatroom. Only use your programming language's standard library.
Details:
The Tcl Chatroom is an online chatroom. Its conversations are logged. It's useful to know if someone has mentioned you or your project in the chatroom r... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | matchFrom[url_String, str_String] := Select[StringSplit[Import[url, "String"], "\n"], StringMatchQ[str]]
getLogLinks[n_] :=
Select[Import["http://tclers.tk/conferences/tcl/", "Hyperlinks"],
First[
StringCases[#1, "tcl/" ~~ date__ ~~ ".tcl" :> DateDifference[DateObject[URLDecode[date], TimeZone -> "Europe/B... | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Summary: Find and print the mentions of a given string in the recent chat logs from a chatroom. Only use your programming language's standard library.
Details:
The Tcl Chatroom is an online chatroom. Its conversations are logged. It's useful to know if som... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singleton | Singleton | A Global Singleton is a class of which only one instance exists within a program.
Any attempt to use non-static members of the class involves performing operations on this one instance.
| #Go | Go | package main
import (
"log"
"math/rand"
"sync"
"time"
)
var (
instance string
once sync.Once // initialize instance with once.Do
)
func claim(color string, w *sync.WaitGroup) {
time.Sleep(time.Duration(rand.Intn(1e8))) // hesitate up to .1 sec
log.Println("trying to claim", col... | Give a code snippet in #Go
A Global Singleton is a class of which only one instance exists within a program.
Any attempt to use non-static members of the class involves performing operations on this one instance.
| 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... | #Ruby | Ruby | def factorial(n)
(1..n).reduce(1, :*)
end
# direct
def catalan_direct(n)
factorial(2*n) / (factorial(n+1) * factorial(n))
end
# recursive
def catalan_rec1(n)
return 1 if n == 0
(0...n).inject(0) {|sum, i| sum + catalan_rec1(i) * catalan_rec1(n-1-i)}
end
def catalan_rec2(n)
return 1 if n == 0
2*(2*... | Give a code snippet in #Ruby
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/Generate_random_chess_position | Generate random chess position | Task
Generate a random chess position in FEN format.
The position does not have to be realistic or even balanced, but it must comply to the following rules:
there is one and only one king of each color (one black king and one white king);
the kings must not be placed on adjacent squares;
there can not be any p... | #Python | Python |
import random
board = [[" " for x in range(8)] for y in range(8)]
piece_list = ["R", "N", "B", "Q", "P"]
def place_kings(brd):
while True:
rank_white, file_white, rank_black, file_black = random.randint(0,7), random.randint(0,7), random.randint(0,7), random.randint(0,7)
diff_list = [abs(rank_white - rank_b... | Give a code snippet in #Python
Task
Generate a random chess position in FEN format.
The position does not have to be realistic or even balanced, but it must comply to the following rules:
there is one and only one king of each color (one black king and one white king);
the kings must not be placed on adjacent ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_factors | Count in factors | Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it would be shown as
2
×
3
{\di... | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program countFactors.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 */
/* for constantes see task include a ... | Give a code snippet in #ARM_Assembly
Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; i... | 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... | #C | C | #include <stdio.h>
#include <string.h>
/* c = a * b. Caller is responsible for memory.
c must not be the same as either a or b. */
void longmulti(const char *a, const char *b, char *c)
{
int i = 0, j = 0, k = 0, n, carry;
int la, lb;
/* either is zero, return "0" */
if (!strcmp(a, "0") || !strcmp(b, "0")) {... | Give a code snippet in #C
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:... | 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... | #Phix | Phix | procedure print_args(sequence args)
for i=1 to length(args) do
?args[i]
end for
end procedure
print_args({"Mary", "had", "a", "little", "lamb"})
| Give a code snippet in #Phix
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.
Re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #M2000_Interpreter | M2000 Interpreter |
Module Checkit {
a=Stack
Stack a {
Push 100, 200, 300
}
Print StackItem(a, 1)=300
Stack a {
Print StackItem(1)=300
While not empty {
Read N
Print N
}
}
}
Checkit
| Give a code snippet in #M2000_Interpreter
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Attractive_numbers | Attractive numbers | A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
Show sequence items up to 120.... | #Scala | Scala | object AttractiveNumbers extends App {
private val max = 120
private var count = 0
private def nFactors(n: Int): Int = {
@scala.annotation.tailrec
def factors(x: Int, f: Int, acc: Int): Int =
if (f * f > x) acc + 1
else
x % f match {
case 0 => factors(x / f, f, acc + 1)
... | Give a code snippet in #Scala
A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
S... | 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).
... | #AutoHotkey | AutoHotkey | S_Expressions(Str){
Str := RegExReplace(Str, "s)(?<![\\])"".*?[^\\]""(*SKIP)(*F)|((?<![\\])[)(]|\s)", "`n$0`n")
Str := RegExReplace(Str, "`am)^\s*\v+") , Cnt := 0
loop, parse, Str, `n, `r
{
Cnt := A_LoopField=")" ? Cnt-1 : Cnt
Res .= tabs(Cnt) A_LoopField "`r`n"
Cnt := A_LoopField="(" ? Cnt+1 : Cnt
}
return... | Give a code snippet in #AutoHotkey
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. MERGESORT.
AUTHOR. DAVE STRATFORD.
DATE-WRITTEN. APRIL 2010.
INSTALLATION. HEXAGON SYSTEMS LIMITED.
**********************************************************... | Give a code snippet in #COBOL
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 so... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multi-dimensional_array | Multi-dimensional array | For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value to update the indexed value.
... | #Java | Java | public class MultiDimensionalArray {
public static void main(String[] args) {
// create a regular 4 dimensional array and initialize successive elements to the values 1 to 120
int m = 1;
int[][][][] a4 = new int[5][4][3][2];
for (int i = 0; i < a4.length; ++i) {
for (int ... | Give a code snippet in #Java
For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #NetRexx | NetRexx | class empty | Give a code snippet in #NetRexx
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | n=100;
tmp=ConstantArray[-1,n];
Do[tmp[[i;;;;i]]*=-1;,{i,n}];
Do[Print["door ",i," is ",If[tmp[[i]]==-1,"closed","open"]],{i,1,Length[tmp]}] | Give a code snippet in #Mathematica.2FWolfram_Language
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 do... | christopher/rosetta-code | |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
Fo... | #Lasso | Lasso | bytes('http://foo bar/') -> encodeurl | Give a code snippet in #Lasso
Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newbie | Hello world/Newbie | Task
Guide a new user of a language through the steps necessary
to install the programming language and selection of a text editor if needed,
to run the languages' example in the Hello world/Text task.
Assume the language-newbie is a programmer in another language.
Assume the language-newbie is competent in install... | #MiniScript | MiniScript | print "Hello World!" | Give a code snippet in #MiniScript
Task
Guide a new user of a language through the steps necessary
to install the programming language and selection of a text editor if needed,
to run the languages' example in the Hello world/Text task.
Assume the language-newbie is a programmer in another language.
Assume the lan... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is o... | #UNIX_Shell | UNIX Shell | #!/usr/bin/env bash
main() {
# Our ten males:
local males=(abe bob col dan ed fred gav hal ian jon)
# And ten females:
local females=(abi bea cath dee eve fay gay hope ivy jan)
# Everyone's preferences, ranked most to least desirable:
local abe=( abi eve cath ivy jan dee fay bea hope gay )
loc... | Give a code snippet in #UNIX_Shell
Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable ... | christopher/rosetta-code | |
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
... | #Java | Java | import java.math.BigInteger;
class IntegerPower {
public static void main(String[] args) {
BigInteger power = BigInteger.valueOf(5).pow(BigInteger.valueOf(4).pow(BigInteger.valueOf(3).pow(2).intValueExact()).intValueExact());
String str = power.toString();
int len = str.length();
S... | Give a code snippet in #Java
Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_common_divisor | Greatest common divisor | Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest common measure.
Related tas... | #MySQL | MySQL |
DROP FUNCTION IF EXISTS gcd;
DELIMITER |
CREATE FUNCTION gcd(x INT, y INT)
RETURNS INT
BEGIN
SET @dividend=GREATEST(ABS(x),ABS(y));
SET @divisor=LEAST(ABS(x),ABS(y));
IF @divisor=0 THEN
RETURN @dividend;
END IF;
SET @gcd=NULL;
SELECT gcd INTO @gcd FROM
(SELECT @tmp:=@dividend,
@divid... | Give a code snippet in #MySQL
Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stirling_numbers_of_the_second_kind | Stirling numbers of the second kind | Stirling numbers of the second kind, or Stirling partition numbers, are the
number of ways to partition a set of n objects into k non-empty subsets. They are
closely related to Bell numbers, and may be derived from them.
Stirling numbers of the second kind obey the recurrence relation:
S2(n, 0) and S2(0, k) = 0 ... | #jq | jq | def lpad($len): tostring | ($len - length) as $l | (" " * $l)[:$l] + .;
# Input: {computed} (the cache)
# Output: {computed, result}
def stirling2($n; $k):
"\($n),\($k)" as $key
| if .computed[$key] then .result = .computed[$key]
elif ($n == 0 and $k == 0) then .result = 1
elif (($n > 0 and $k == 0) or (... | Give a code snippet in #jq
Stirling numbers of the second kind, or Stirling partition numbers, are the
number of ways to partition a set of n objects into k non-empty subsets. They are
closely related to Bell numbers, and may be derived from them.
Stirling numbers of the second kind obey the recurrence relation:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Totient_function | Totient function | The totient function is also known as:
Euler's totient function
Euler's phi totient function
phi totient function
Φ function (uppercase Greek phi)
φ function (lowercase Greek phi)
Definitions (as per number theory)
The totient function:
counts the integers up to a given positiv... | #Factor | Factor | USING: combinators formatting io kernel math math.primes.factors
math.ranges sequences ;
IN: rosetta-code.totient-function
: Φ ( n -- m )
{
{ [ dup 1 < ] [ drop 0 ] }
{ [ dup 1 = ] [ drop 1 ] }
[
dup unique-factors
[ 1 [ 1 - * ] reduce ] [ product ] bi / *
]... | Give a code snippet in #Factor
The totient function is also known as:
Euler's totient function
Euler's phi totient function
phi totient function
Φ function (uppercase Greek phi)
φ function (lowercase Greek phi)
Definitions (as per number theory)
The totient function:
counts th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_an_array_of_composite_structures | Sort an array of composite structures |
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
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | events = {{"2009-12-25", "Christmas Day"}, {"2009-04-22",
"Earth Day"}, {"2009-09-07", "Labor Day"}, {"2009-07-04",
"Independence Day"}, {"2009-10-31", "Halloween"}, {"2009-05-25",
"Memorial Day"}, {"2009-03-14", "PI Day"}, {"2009-01-01",
"New Year's Day"}, {"2009-12-31",
"New Year's Eve"}, {"2... | Give a code snippet in #Mathematica.2FWolfram_Language
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 |... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pernicious_numbers | Pernicious numbers | A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime, and therefore
22 is a pe... | #11l | 11l | F popcount(n)
R bin(n).count(‘1’)
F is_prime(n)
I n < 2
R 0B
L(i) 2 .. Int(sqrt(n))
I n % i == 0
R 0B
R 1B
V i = 0
V cnt = 0
L
I is_prime(popcount(i))
print(i, end' ‘ ’)
cnt++
I cnt == 25
L.break
i++
print()
L(i) 888888877..888888888
I is_prime(... | Give a code snippet in #11l
A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime, ... | christopher/rosetta-code |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.