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/Continued_fraction | Continued fraction | continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to write a program which generates su... | #Picat | Picat | go =>
% square root 2
continued_fraction(200, sqrt_2_ab, V1),
printf("sqrt(2) = %w (diff: %0.15f)\n", V1, V1-sqrt(2)),
% napier
continued_fraction(200, napier_ab, V2),
printf("e = %w (diff: %0.15f)\n", V2, V2-math.e),
% pi
continued_fraction(200, pi_ab, V3),
printf("pi = %w (diff: %0.... | Give a code snippet in #Picat
continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to wri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Oz | Oz | {Show "Hello world!"} | Give a code snippet in #Oz
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
H... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_word/fractal | Fibonacci word/fractal |
The Fibonacci word may be represented as a fractal as described here:
(Clicking on the above website (hal.archives-ouvertes.fr) will leave a cookie.)
For F_wordm start with F_wordCharn=1
Draw a segment forward
If current F_wordChar is 0
Turn left if n is even
Turn right if n is odd
next n and iterate until e... | #Java | Java | import java.awt.*;
import javax.swing.*;
public class FibonacciWordFractal extends JPanel {
String wordFractal;
FibonacciWordFractal(int n) {
setPreferredSize(new Dimension(450, 620));
setBackground(Color.white);
wordFractal = wordFractal(n);
}
public String wordFractal(int... | Give a code snippet in #Java
The Fibonacci word may be represented as a fractal as described here:
(Clicking on the above website (hal.archives-ouvertes.fr) will leave a cookie.)
For F_wordm start with F_wordCharn=1
Draw a segment forward
If current F_wordChar is 0
Turn left if n is even
Turn right if n is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_numbers | Perfect numbers | Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself).
Note: The faster Luca... | #Lua | Lua | function isPerfect(x)
local sum = 0
for i = 1, x-1 do
sum = (x % i) == 0 and sum + i or sum
end
return sum == x
end | Give a code snippet in #Lua
Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself).... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anti-primes | Anti-primes | The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| #Raku | Raku | sub propdiv (\x) {
my @l = 1 if x > 1;
(2 .. x.sqrt.floor).map: -> \d {
unless x % d { @l.push: d; my \y = x div d; @l.push: y if y != d }
}
@l
}
my $last = 0;
my @anti-primes = lazy 1, |(|(2..59), 60, *+60 … *).grep: -> $c {
my \mx = +propdiv($c);
next if mx <= $last;
$last = mx... | Give a code snippet in #Raku
The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| christopher/rosetta-code | |
http://rosettacode.org/wiki/21_game | 21 game | 21 game
You are encouraged to solve this task according to the task description, using any language you may know.
21 is a two player game, the game is played by choosing
a number (1, 2, or 3) to be added to the running total.
The game is won by the player whose chosen number causes the running total
to reach exactly ... | #Go | Go | package main
import (
"bufio"
"fmt"
"log"
"math/rand"
"os"
"strconv"
"time"
)
var scanner = bufio.NewScanner(os.Stdin)
var (
total = 0
quit = false
)
func itob(i int) bool {
if i == 0 {
return false
}
return true
}
func getChoice() {
for {
f... | Give a code snippet in #Go
21 game
You are encouraged to solve this task according to the task description, using any language you may know.
21 is a two player game, the game is played by choosing
a number (1, 2, or 3) to be added to the running total.
The game is won by the player whose chosen number causes the run... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bead_sort | Sorting algorithms/Bead 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
... | #ooRexx | ooRexx | in='10 -12 1 0 999 8 2 2 4 4'
Do i=1 To words(in)
z.i=word(in,i)
End
n=i-1
init=0
Call minmax
beads.=0;
Do i=1 To words(in)
z=z.i
beads.z+=1
End
j=0
Do i=lo To hi
Do While beads.i>0
j+=1
s.j=i
beads.i-=1
End;
End;
Call show ' Input:',z.,n
Call show 'Sorted:',s.,n
Ex... | Give a code snippet in #ooRexx
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 s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pascal%27s_triangle/Puzzle | Pascal's triangle/Puzzle | This puzzle involves a Pascals Triangle, also known as a Pyramid of Numbers.
[ 151]
[ ][ ]
[40][ ][ ]
[ ][ ][ ][ ]
[ X][11][ Y][ 4][ Z]
Each brick of the pyramid is the sum of the two bricks situated below it.
Of the three missing numbers at the base of the pyramid,
the... | #Racket | Racket |
#lang racket/base
(require racket/list)
(struct cell (v x z) #:transparent)
(define (cell-add cx cy)
(cell (+ (cell-v cx) (cell-v cy))
(+ (cell-x cx) (cell-x cy))
(+ (cell-z cx) (cell-z cy))))
(define (cell-sub cx cy)
(cell (- (cell-v cx) (cell-v cy))
(- (cell-x cx) (cell-x cy))
... | Give a code snippet in #Racket
This puzzle involves a Pascals Triangle, also known as a Pyramid of Numbers.
[ 151]
[ ][ ]
[40][ ][ ]
[ ][ ][ ][ ]
[ X][11][ Y][ 4][ Z]
Each brick of the pyramid is the sum of the two bricks situated below it.
Of the three missing numbers... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/Continuous | Knapsack problem/Continuous |
A thief burgles a butcher's shop, where he can select from some items.
The thief knows the weights and prices of each items. Because he has a knapsack with 15 kg maximal capacity, he wants to select the items such that he would have his profit maximized. He may cut the items; the item has a reduced price after... | #R | R |
knapsack<- function(Value, Weight, Objects, Capacity){
Fraction = rep(0, length(Value))
Cost = Value/Weight
#print(Cost)
W = Weight[order(Cost, decreasing = TRUE)]
Obs = Objects[order(Cost, decreasing = TRUE)]
Val = Value[order(Cost, decreasing = TRUE)]
#print(W)
RemainCap = Capacity
i = 1
n = len... | Give a code snippet in #R
A thief burgles a butcher's shop, where he can select from some items.
The thief knows the weights and prices of each items. Because he has a knapsack with 15 kg maximal capacity, he wants to select the items such that he would have his profit maximized. He may cut the items; the ite... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously | Loop over multiple arrays simultaneously | Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this example, loop over the arrays:
... | #zkl | zkl | foreach a,b,c in (["a".."c"].zip(T("A","B","C"),[1..])){ println(a,b,c) } | Give a code snippet in #zkl
Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this exampl... | 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... | #Swift | Swift | func powersetFrom<T>(_ elements: Set<T>) -> Set<Set<T>> {
guard elements.count > 0 else {
return [[]]
}
var powerset: Set<Set<T>> = [[]]
for element in elements {
for subset in powerset {
powerset.insert(subset.union([element]))
}
}
return powerset
}
// Example:
powersetFrom([1, 2, 4]) | Give a code snippet in #Swift
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (i... | #Nim | Nim | proc Query*(data: var array[1024, char], length: var cint): cint {.exportc.} =
const text = "Here am I"
if length < text.len:
return 0
for i in 0 .. text.high:
data[i] = text[i]
length = text.len
return 1 | Give a code snippet in #Nim
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, si... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Root_mean_square | Averages/Root mean square | Task[edit]
Compute the Root mean square of the numbers 1..10.
The root mean square is also known by its initials RMS (or rms), and as the quadratic mean.
The RMS is calculated as the mean of the squares of the numbers, square-rooted:
x
r
m
s
=
x
1
2
+
x
2
2
+
⋯
+
x
... | #Oforth | Oforth | 10 seq map(#sq) sum 10.0 / sqrt . | Give a code snippet in #Oforth
Task[edit]
Compute the Root mean square of the numbers 1..10.
The root mean square is also known by its initials RMS (or rms), and as the quadratic mean.
The RMS is calculated as the mean of the squares of the numbers, square-rooted:
x
r
m
s
=
x
1
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For | Loops/For | “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers.
... | #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. Display-Triangle.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 Outer-Counter PIC 9.
01 Inner-Counter PIC 9.
PROCEDURE DIVISION.
PERFORM VARYING Outer-Counter FROM 1 BY 1 UNTIL 5 < Outer-Counter
PERFORM VARYING... | Give a code snippet in #COBOL
“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams/Deranged_anagrams | Anagrams/Deranged anagrams | Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
Task[edit]
Use the word list at uni... | #PureBasic | PureBasic | Structure anagram
word.s
letters.s
EndStructure
Structure wordList
List words.anagram()
EndStructure
#True = 1
#False = 0
Procedure.s sortLetters(*word.Character, wordLength)
;returns a string with the letters of a word sorted
Protected Dim letters.c(wordLength)
Protected *letAdr = @letters()
CopyM... | Give a code snippet in #PureBasic
Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_missing_permutation | Find the missing permutation | ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
CDBA
... | #C.23 | C# | using System;
using System.Collections.Generic;
namespace MissingPermutation
{
class Program
{
static void Main()
{
string[] given = new string[] { "ABCD", "CABD", "ACDB", "DACB",
"BCDA", "ACBD", "ADCB", "CDAB",
... | Give a code snippet in #C.23
ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #C.23 | C# | using System;
class Program
{
static string Reverse(string value)
{
char[] chars = value.ToCharArray();
Array.Reverse(chars);
return new string(chars);
}
static bool IsPalindrome(string value)
{
return value == Reverse(value);
}
static void Main(string[]... | Give a code snippet in #C.23
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as ... | 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.
| #VBScript | VBScript |
Function greatest_element(arr)
tmp_num = 0
For i = 0 To UBound(arr)
If i = 0 Then
tmp_num = arr(i)
ElseIf arr(i) > tmp_num Then
tmp_num = arr(i)
End If
Next
greatest_element = tmp_num
End Function
WScript.Echo greatest_element(Array(1,2,3,44,5,6,8))
| Give a code snippet in #VBScript
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/Look-and-say_sequence | Look-and-say sequence | The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, 11, 21, 1211, 11122... | #8086_Assembly | 8086 Assembly | bits 16
cpu 8086
puts: equ 9h ; MS/DOS system call to print a string
nmemb: equ 15 ; Change this to print more or fewer members
section .text
org 100h
mov cx,nmemb ; CX = how many members to print
outloop: mov dx,memb ; Print current member
mov ah,puts
int 21h
mov dx,newline ; Print newline
int 21h
... | Give a code snippet in #8086_Assembly
The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_float_arrays_to_a_text_file | Write float arrays to a text file | Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2, 3, 1e11};
y = {1, 1.41421356... | #Common_Lisp | Common Lisp | (with-open-file (stream (make-pathname :name "filename") :direction :output)
(let* ((x (make-array 4 :initial-contents '(1 2 3 1e11)))
(y (map 'vector 'sqrt x))
(xprecision 3)
(yprecision 5)
(fmt (format nil "~~,1,~d,,G~~12t~~,~dG~~%" xprecision yprecision)))
... | Give a code snippet in #Common_Lisp
Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {... | 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.
| #PureBasic | PureBasic | Procedure Cube(Array param.i(1))
Protected n.i
For n = 0 To ArraySize(param())
Debug Str(param(n)) + "^3 = " + Str(param(n) * param(n) * param(n))
Next
EndProcedure
Dim AnArray.i(4)
For n = 0 To ArraySize(AnArray())
AnArray(n) = Random(99)
Next
Cube(AnArray()) | Give a code snippet in #PureBasic
Task
Take a combined set of elements and apply a function to each element.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this wil... | #C | C | #include <stdio.h>
#define TALLOC(n,typ) malloc(n*sizeof(typ))
#define EL_Type int
typedef struct sMtx {
int dim_x, dim_y;
EL_Type *m_stor;
EL_Type **mtx;
} *Matrix, sMatrix;
typedef struct sRvec {
int dim_x;
EL_Type *m_stor;
} *RowVec, sRowVec;
Matrix NewMatrix( int x_dim, int y_dim... | Give a code snippet in #C
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hunt_the_Wumpus | Hunt the Wumpus | This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game is set in a cave that consists ... | #Rust | Rust |
-- HUNT THE WUMPUS
-- BY GREGORY YOB
-- SenseTalk adaptation by Jonathan Gover
answer "INSTRUCTIONS (Y-N)" with "No" or "Yes"
if it is "Yes" then showInstructions
-- SET UP CAVE (DODECAHEDRAL NODE LIST)
set rooms to [
[2,5,8],[1,3,10],[2,4,12],[3,5,14],[1,4,6],
[5,7,15],[6,8,17],[1,7,9],[8,10,18],[2,9,11],
[1... | Give a code snippet in #Rust
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Strand_sort | Sorting algorithms/Strand 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
... | #D | D | import std.stdio, std.container;
DList!T strandSort(T)(DList!T list) {
static DList!T merge(DList!T left, DList!T right) {
DList!T result;
while (!left.empty && !right.empty) {
if (left.front <= right.front) {
result.insertBack(left.front);
left.removeFr... | Give a code snippet in #D
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/Pythagorean_quadruples | Pythagorean quadruples |
One form of Pythagorean quadruples is (for positive integers a, b, c, and d):
a2 + b2 + c2 = d2
An example:
22 + 32 + 62 = 72
which is:
4 + 9 + 36 = 49
Task
For positive integers up 2,200 (inclusive), for all values of ... | #Raku | Raku | my \N = 2200;
my @sq = (0 .. N)»²;
my @not = False xx N;
@not[0] = True;
(1 .. N).race.map: -> $d {
my $last = 0;
for $d ... ($d/3).ceiling -> $a {
for 1 .. ($a/2).ceiling -> $b {
last if (my $ab = @sq[$a] + @sq[$b]) > @sq[$d];
if (@sq[$d] - $ab).sqrt.narrow ~~ Int {
... | Give a code snippet in #Raku
One form of Pythagorean quadruples is (for positive integers a, b, c, and d):
a2 + b2 + c2 = d2
An example:
22 + 32 + 62 = 72
which is:
4 + 9 + 36 = 49
Task
For positive integers up 2,200 (incl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Price_fraction | Price fraction | A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to ... | #Quackery | Quackery | [ $ 'bigrat.qky' loadfile ] now!
[ 2over 2over v< if 2swap 2drop ] is vmax ( n/d n/d --> n/d )
[ 100 1 v* 1 1 v-
0 1 vmax 5 1 v/ /
[ table
10 18 26 32 38
44 50 54 58 62
66 70 74 78 82
86 90 94 98 100 ] 100 ] is scale ( n/d --> n/d )
[ swap echo sp echo ] is br ( n/d ... | Give a code snippet in #Quackery
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
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 |... | #Java | Java | public static String Substring(String str, int n, int m){
return str.substring(n, n+m);
}
public static String Substring(String str, int n){
return str.substring(n);
}
public static String Substring(String str){
return str.substring(0, str.length()-1);
}
public static String Substring(String str, char c, in... | Give a code snippet in #Java
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/Keyboard_macros | Keyboard macros | Show how to link user defined methods to user defined keys.
An example of this is the facility provided by emacs for key bindings.
These key bindings may be application-specific or system-wide; state which you have done.
| #Vedit_macro_language | Vedit macro language | // Configure a key to access menu item.
// The menu item may then contain the commands directly, or it may call a macro from disk.
// This has the advantage that the key binding is shown in the menu.
Key_Add("Shft-F6","[MENU]TV", OK)
// Configure a key to perform visual mode edit operations (similar to recorded key ... | Give a code snippet in #Vedit_macro_language
Show how to link user defined methods to user defined keys.
An example of this is the facility provided by emacs for key bindings.
These key bindings may be application-specific or system-wide; state which you have done.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously | Loop over multiple arrays simultaneously | Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this example, loop over the arrays:
... | #360_Assembly | 360 Assembly | * Loop over multiple arrays simultaneously 09/03/2017
LOOPSIM CSECT
USING LOOPSIM,R12 base register
LR R12,R15
LA R6,1 i=1
LA R7,3 counter=3
LOOP LR R1,R6 i
SLA R1,1 *2
LH... | Give a code snippet in #360_Assembly
Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Named_parameters | Named parameters | Create a function which takes in a number of arguments which are specified by name rather than (necessarily) position, and show how to call the function. If the language supports reordering the arguments or optionally omitting some of them, note this.
Note:
Named parameters relies on being able to use the names give... | #Racket | Racket |
#lang racket
(define (pizza sauce
;; mandatory keyword argument
#:topping topping
;; optional keyword argument with default
#:type [type "deep dish"])
(printf "~a pizza with ~a sauce topped with ~a~n"
type sauce topping))
(pizza "tomato" #:to... | Give a code snippet in #Racket
Create a function which takes in a number of arguments which are specified by name rather than (necessarily) position, and show how to call the function. If the language supports reordering the arguments or optionally omitting some of them, note this.
Note:
Named parameters relies on ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #PureBasic | PureBasic | Procedure SumOfSquares(List base())
ForEach base()
Sum + base()*base()
Next
ProcedureReturn Sum
EndProcedure | Give a code snippet in #PureBasic
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
... | #Racket | Racket |
#lang racket
(define (sierpinski n)
(if (zero? n)
'("*")
(let ([spaces (make-string (expt 2 (sub1 n)) #\space)]
[prev (sierpinski (sub1 n))])
(append (map (λ(x) (~a spaces x spaces)) prev)
(map (λ(x) (~a x " " x)) prev)))))
(for-each displayln (sierpinski 5))
| Give a code snippet in #Racket
Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Look-and-say_sequence | Look-and-say sequence | The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, 11, 21, 1211, 11122... | #M4 | M4 | divert(-1)
define(`for',
`ifelse($#,0,``$0'',
`ifelse(eval($2<=$3),1,
`pushdef(`$1',$2)$4`'popdef(`$1')$0(`$1',incr($2),$3,`$4')')')')
define(`las',
`patsubst(`$1',`\(\(.\)\2*\)',`len(\1)`'\2')')
define(`v',1)
divert
for(`x',1,10,
`v
define(`v',las(v))')dnl
v | Give a code snippet in #M4
The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Haversine_formula | Haversine formula |
This page uses content from Wikipedia. The original article was at Haversine formula. 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)
The haversine formula is an equation important in navigation, g... | #X86_Assembly | X86 Assembly | 0000 .model tiny
0000 .code
.486
org 100h ;.com files start here
0100 9B DB E3 start: finit ;initialize floating-point unit (FPU)
... | Give a code snippet in #X86_Assembly
This page uses content from Wikipedia. The original article was at Haversine formula. 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)
The haversine formula is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_format | Date format | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| #Swift | Swift | import Foundation
extension String {
func toStandardDateWithDateFormat(format: String) -> String {
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = format
dateFormatter.dateStyle = .LongStyle
return dateFormatter.stringFromDate(dateFormatter.dateFromString(self)!)
... | Give a code snippet in #Swift
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Jump_anywhere | Jump anywhere | Imperative programs
conditional structures
loops
local jumps
This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports.
For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to use these jumps for different... | #Raku | Raku | outer-loop: loop {
inner-loop: loop {
# NYI # goto inner-loop if rand > 0.5; # Hard goto
next inner-loop if rand > 0.5; # Next loop iteration
redo inner-loop if rand > 0.5; # Re-execute block
last outer-loop if rand > 0.5; # Exit the loop
ENTER { s... | Give a code snippet in #Raku
Imperative programs
conditional structures
loops
local jumps
This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports.
For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation | Horner's rule for polynomial evaluation | A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\displaystyle ((((0)x+6)x+(-4))x... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | Horner[l_List, x_] := Fold[x #1 + #2 &, 0, l]
Horner[{6, -4, 7, -19}, x]
-> -19 + x (7 + x (-4 + 6 x))
-19 + x (7 + x (-4 + 6 x)) /. x -> 3
-> 128 | Give a code snippet in #Mathematica_.2F_Wolfram_Language
A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/Floating_point | Literals/Floating point | Programming languages have different ways of expressing floating-point literals.
Task
Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features.
You may want to include a regular expression or BNF/ABNF/EBNF defining allowable fo... | #Vim_Script | Vim Script | Sub Main()
Dim d As Double ' 8 Bytes, type specifier = #
Dim s As Single ' 4 Bytes, type specifier = !
d = -12.3456
d = 1000#
d = 0.00001
d = 67#
d = 8.9
d = 0.33
d = 0#
d = 2# * 10 ^ 3
d = 2E+50
d = 2E-50
s = -12.3456!
s = 1000!
s = 0.00001!
s = 67!
s = 8.9!
s = 0.33!
s = 0!
s = 2! ... | Give a code snippet in #Vim_Script
Programming languages have different ways of expressing floating-point literals.
Task
Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features.
You may want to include a regular expression or... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | Public Function Ackermann(m As Float, n As Float) As Float
If m = 0 Then
Return n + 1
End If
If n = 0 Then
Return Ackermann(m - 1, 1)
End If
Return Ackermann(m - 1, Ackermann(m, n - 1))
End
Public Sub Main()
Dim m, n As Float
For m = 0 To 3
For n = 0 To 4
Print "Ackermann("; m; ", "; n... | Give a code snippet in #F.C5.8Drmul.C3.A6
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Linear_congruential_generator | Linear congruential generator | The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_{0}}
is a seed.
r
1
... | #dc | dc | [*
* lrx -- (random number from 0 to 2147483647)
*
* Returns a number from the BSD rand() sequence.
* Seeded by storing a seed in register R.
*]sz
[lR 1103515245 * 12345 + 2147483648 % d sR]sr
[* Set seed to 1, then print the first 3 random numbers. *]sz
1 sR
lrx psz lrx psz lrx psz | Give a code snippet in #dc
The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_{0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Archimedean_spiral | Archimedean spiral |
The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.
An Archimedean spiral can be described by the equation:
r
=
a
+
b
θ
{\displaystyle \,r=a+b\theta }
with real numbers a and b.
Task
Draw an Archimedean spiral.
| #jq | jq | def spiral($zero; $turns; $step):
def pi: 1 | atan * 4;
def p2: (. * 100 | round) / 100;
def svg:
400 as $width
| 400 as $height
| 2 as $swidth # stroke
| "blue" as $stroke
| (range($zero; $turns * 2 * pi; $step) as $theta
| (((($theta)|cos) * 2 * $theta + ($width/2)) |p2) as $x
... | Give a code snippet in #jq
The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.
An Archimedean spiral can be described by the equation:
r
=
a
+
b
θ
{\displaystyle \,r=a+b\theta }
with real numbers a and b.
Task
Draw an Archimedean spiral.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #REBOL | REBOL | rebol [
Title: "Align Columns"
URL: http://rosettacode.org/wiki/Align_columns
]
specimen: {Given$a$text$file$of$many$lines,$where$fields$within$a$line$
are$delineated$by$a$single$'dollar'$character,$write$a$program
that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$
column$are$separated$by$at$least$on... | Give a code snippet in #REBOL
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either lef... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Top_rank_per_group | Top rank per group | Task
Find the top N salaries in each department, where N is provided as a parameter.
Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source:
Employee Name,Employee ID,Salary,Department
Tyler Bennett... | #Erlang | Erlang | <-module( top_rank_per_group ).
-export( [employees/0, employees_in_department/2, highest_payed/2, task/1] ).
-record( employee, {name, id, salery, department} ).
employees() ->
[#employee{name="Tyler Bennett", id="E10297", salery=32000, department="D101"},
#employee{name="John Rappl", id="E21437", s... | Give a code snippet in #Erlang
Task
Find the top N salaries in each department, where N is provided as a parameter.
Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source:
Employee Name,Employee ID... | 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 ... | #Raku | Raku | spurt "output.txt", slurp "input.txt"; | Give a code snippet in #Raku
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 in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/1 | Text processing/1 | This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Often data is produced by one program, in the wrong format for later use by another program or person. In these situations another pr... | #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. data-munging.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT input-file ASSIGN TO INPUT-FILE-PATH
ORGANIZATION LINE SEQUENTIAL
FILE STATUS file-status.
DATA DIVISION.
FILE... | Give a code snippet in #COBOL
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Often data is produced by one program, in the wrong format for later use by another program or person.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Main_step_of_GOST_28147-89 | Main step of GOST 28147-89 | GOST 28147-89 is a standard symmetric encryption based on a Feistel network.
The structure of the algorithm consists of three levels:
encryption modes - simple replacement, application range, imposing a range of feedback and authentication code generation;
cycles - 32-З, 32-Р and 16-З, is a repetition of the ... | #BBC_BASIC | BBC BASIC | DIM table&(7,15), test%(1)
table&() = 4, 10, 9, 2, 13, 8, 0, 14, 6, 11, 1, 12, 7, 15, 5, 3, \
\ 14, 11, 4, 12, 6, 13, 15, 10, 2, 3, 8, 1, 0, 7, 5, 9, \
\ 5, 8, 1, 13, 10, 3, 4, 2, 14, 15, 12, 7, 6, 0, 9, 11, \
\ 7, 13, 10, 1, 0, ... | Give a code snippet in #BBC_BASIC
GOST 28147-89 is a standard symmetric encryption based on a Feistel network.
The structure of the algorithm consists of three levels:
encryption modes - simple replacement, application range, imposing a range of feedback and authentication code generation;
cycles - 32-З, 32-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N%27th | N'th | Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show here the output for at least t... | #Lambdatalk | Lambdatalk |
{def fnOrdinalForm
{lambda {:n}
{if {and {<= 11 {% :n 100}} {>= 13 {% :n 100}}}
then :nth
else :n{A.get {% :n 10} th st nd rd th th th th th th}}}}
-> fnOrdinalForm
{S.map fnOrdinalForm {S.serie 0 25}}
-> 0th 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th
16th 17th 18th 19th 20th 21st ... | Give a code snippet in #Lambdatalk
Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Entropy/Narcissist | Entropy/Narcissist |
Task
Write a computer program that computes and shows its own entropy.
Related Tasks
Fibonacci_word
Entropy
| #Raku | Raku | say log(2) R/ [+] map -> \p { p * -log p }, $_.comb.Bag.values >>/>> +$_
given slurp($*PROGRAM-NAME).comb | Give a code snippet in #Raku
Task
Write a computer program that computes and shows its own entropy.
Related Tasks
Fibonacci_word
Entropy
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #ActionScript | ActionScript | public static function factorial(n:int):int
{
if (n < 0)
return 0;
var fact:int = 1;
for (var i:int = 1; i <= n; i++)
fact *= i;
return fact;
} | Give a code snippet in #ActionScript
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #Yorick | Yorick | func is_palindrome(str) {
s = strchar(str)(:-1);
return allof(s == s(::-1));
}
func prep_palindrome(str) {
s = strchar(strlower(str));
w = where(s >= 'a' & s <= 'z');
return strchar(s(w));
} | Give a code snippet in #Yorick
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Barnsley_fern | Barnsley fern |
A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS).
Task
Create this fractal fern, using the following transformations:
ƒ1 (chosen 1% of the time)
xn + 1 = 0
yn + 1 = 0.16 yn
ƒ2 (chosen 85% of the time)
... | #Frink | Frink |
g = new graphics
g.backgroundColor[0,0,0] // black
g.color[0,0.5,0] // green
x = 0
y = 0
for i = 1 to 100000
{
g.fillEllipseCenter[x*10,y*-10,0.25,0.25]
z = random[1, 100]
if z == 1
{
xn = 0
yn = 0.16 * y
}
if z >= 2 and z <= 86
{
xn = 0.85 * x + 0.04 * y
yn = -0.04 * ... | Give a code snippet in #Frink
A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS).
Task
Create this fractal fern, using the following transformations:
ƒ1 (chosen 1% of the time)
xn + 1 = 0
yn + 1 = 0.16 yn
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
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 l... | #zkl | zkl | while(1) { println("SPAM") }
while(True){ println("SPAM") }
foreach _ in ([0..]){ println("SPAM") }
[0..].pump(Console.println,T(Void,"SPAM"));
[0..].pump(fcn{ println("SPAM") });
fcn{ println("SPAM"); return(self.fcn()) }(); // tail recursive lambda | Give a code snippet in #zkl
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jensen%27s_Device | Jensen's Device | Jensen's Device
You are encouraged to solve this task according to the task description, using any language you may know.
This task is an exercise in call by name.
Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the ALGOL 60 Report.
The following pr... | #M4 | M4 | define(`for',
`ifelse($#,0,``$0'',
`ifelse(eval($2<=$3),1,
`pushdef(`$1',$2)$4`'popdef(`$1')$0(`$1',incr($2),$3,`$4')')')')
define(`sum',
`pushdef(`temp',0)`'for(`$1',$2,$3,
`define(`temp',eval(temp+$4))')`'temp`'popdef(`temp')')
sum(`i',1,100,`1000/i') | Give a code snippet in #M4
Jensen's Device
You are encouraged to solve this task according to the task description, using any language you may know.
This task is an exercise in call by name.
Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the ALGOL ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Wren | Wren | import "io" for File
import "/ioutil" for FileUtil
class Configuration {
construct new(map) {
_fullName = map["fullName"]
_favouriteFruit = map["favouriteFruit"]
_needsPeeling = map["needsPeeling"]
_seedsRemoved = map["seedsRemoved"]
_otherFamily = map["otherFa... | Give a code snippet in #Wren
The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Logical_operations | Logical operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #ALGOL_68 | ALGOL 68 | PROC print_logic = (BOOL a, b)VOID:
(
# for a 6-7 bit/byte compiler #
printf(($"a and b is "gl$, a AND b);
printf(($"a or b is "gl$, a OR b);
printf(($"not a is "gl$, NOT a);
printf(($"a equivalent to b is "gl$, a EQ b);
printf(($"a not equivalent to b is "gl$, a NE b);
# Alternatively ASCII #
printf(($"... | Give a code snippet in #ALGOL_68
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 Operatio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #AutoIt | AutoIt | ;AutoIt Version: 3.2.10.0
$depth=0
recurse($depth)
Func recurse($depth)
ConsoleWrite($depth&@CRLF)
Return recurse($depth+1)
EndFunc | Give a code snippet in #AutoIt
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_Machin-like_formulas | Check Machin-like formulas | Machin-like formulas are useful for efficiently computing numerical approximations for
π
{\displaystyle \pi }
Task
Verify the following Machin-like formulas are correct by calculating the value of tan (right hand side) for each equation using exact arithmetic and showing they equal 1:
π
4
=
ar... | #R | R |
#lang R
library(Rmpfr)
prec <- 1000 # precision in bits
`%:%` <- function(e1, e2) '/'(mpfr(e1, prec), mpfr(e2, prec)) # operator %:% for high precision division
# function for checking identity of tan of expression and 1, making use of high precision division operator %:%
tanident_1 <- function(x) identical(round(tan... | Give a code snippet in #R
Machin-like formulas are useful for efficiently computing numerical approximations for
π
{\displaystyle \pi }
Task
Verify the following Machin-like formulas are correct by calculating the value of tan (right hand side) for each equation using exact arithmetic and showing they ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #C | C | #include <stdio.h>
#include <stdlib.h>
int dot_product(int *, int *, size_t);
int
main(void)
{
int a[3] = {1, 3, -5};
int b[3] = {4, -2, -1};
printf("%d\n", dot_product(a, b, sizeof(a) / sizeof(a[0])));
return EXIT_SUCCESS;
}
int
dot_product(int *a, int *b, size_t n)
{
... | Give a code snippet in #C
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1] ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers | Luhn test of credit card numbers | The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of the digits in the number.
Tak... | #FreeBASIC | FreeBASIC | ' version 05-07-2015
' compile with: fbc -s console
#Ifndef TRUE ' define true and false for older freebasic versions
#Define FALSE 0
#Define TRUE Not FALSE
#EndIf
Function luhntest(cardnr As String) As Integer
cardnr = Trim(cardnr) ' we don't want spaces
Dim As String reverse_nr = cardnr
... | Give a code snippet in #FreeBASIC
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the orde... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/String | Literals/String | Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
Here document
Other tasks r... | #Xojo | Xojo | Dim s As String = "Tom said, ""The fox ran away."""
Result: Tom said, "The fox ran away." | Give a code snippet in #Xojo
Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Median | Averages/Median | Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle values.
There are several approaches ... | #Octave | Octave | function y = median2(v)
if (numel(v) < 1)
y = NA;
else
sv = sort(v);
l = numel(v);
if ( mod(l, 2) == 0 )
y = (sv(floor(l/2)+1) + sv(floor(l/2)))/2;
else
y = sv(floor(l/2)+1);
endif
endif
endfunction
a = [4.1, 5.6, 7.2, 1.7, 9.3, 4.4, 3.2];
b = [4.1, 7.2, 1.7, 9.3, 4.4, 3.2];
... | Give a code snippet in #Octave
Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle values... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #JavaScript | JavaScript | var a;
typeof(a) === "undefined";
typeof(b) === "undefined";
var obj = {}; // Empty object.
typeof(obj.c) === "undefined";
obj.c = 42;
obj.c === 42;
delete obj.c;
typeof(obj.c) === "undefined"; | Give a code snippet in #JavaScript
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
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 |... | #Smalltalk | Smalltalk | | a b |
'Input number a: ' display.
a := (stdin nextLine) asInteger.
'Input number b: ' display.
b := (stdin nextLine) asInteger.
('a+b=%1' % { a + b }) displayNl.
('a-b=%1' % { a - b }) displayNl.
('a*b=%1' % { a * b }) displayNl.
('a/b=%1' % { a // b }) displayNl.
('a%%b=%1' % { a \\ b }) displayNl. | Give a code snippet in #Smalltalk
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 Operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Keypress_check | Keyboard input/Keypress check |
Determine if a key has been pressed and store this in a variable.
If no key has been pressed, the program should continue without waiting.
| #Euphoria | Euphoria | integer key
key = get_key() -- if key was not pressed get_key() returns -1 | Give a code snippet in #Euphoria
Determine if a key has been pressed and store this in a variable.
If no key has been pressed, the program should continue without waiting.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_time_of_day | Averages/Mean time of day | Task[edit]
A particular activity of bats occurs at these times of the day:
23:00:17, 23:40:20, 00:12:45, 00:17:19
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using the ideas of Averages/Mean angle
compute ... | #Java | Java | public class MeanTimeOfDay {
static double meanAngle(double[] angles) {
int len = angles.length;
double sinSum = 0.0;
for (int i = 0; i < len; i++) {
sinSum += Math.sin(angles[i] * Math.PI / 180.0);
}
double cosSum = 0.0;
for (int i = 0; i < len; i++) ... | Give a code snippet in #Java
Task[edit]
A particular activity of bats occurs at these times of the day:
23:00:17, 23:40:20, 00:12:45, 00:17:19
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using the ideas o... | 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 ... | #Datalog | Datalog | .decl Fib(i:number, x:number)
Fib(0, 0).
Fib(1, 1).
Fib(i+2,x+y) :- Fib(i+1, x), Fib(i, y), i+2<=40, i+2>=2.
Fib(i-2,y-x) :- Fib(i-1, x), Fib(i, y), i-2>=-40, i-2<0. | Give a code snippet in #Datalog
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 a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref savelog symbols binary
harry = [long 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
sum = long 0
product = long 1
entries = Rexx ''
loop n_ = int 0 to harry.length - 1
nxt = harry[n_]
entries = entries nxt
sum = sum + nxt
product = product * nxt
end n_
en... | Give a code snippet in #NetRexx
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_cuboid | Draw a cuboid | Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is acceptable for this task.
R... | #Tcl | Tcl | package require Tcl 8.5
package require Tk
package require math::linearalgebra
package require math::constants
# Helper for constructing a rectangular face in 3D
proc face {px1 py1 pz1 px2 py2 pz2 px3 py3 pz3 px4 py4 pz4 color} {
set centroidX [expr {($px1+$px2+$px3+$px4)/4.0}]
set centroidY [expr {($py1+$py2... | Give a code snippet in #Tcl
Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is a... | christopher/rosetta-code | |
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... | #TI-89_BASIC | TI-89 BASIC | ■ √(–1)
■ ^2 —1
■ + 1 1 +
■ (1+) * 2 2 + 2*
■ (1+) (2) —2 + 2*
■ —(1+) —1 -
■ 1/(2) —1 -
■ real(1 + 2) 1
■ imag(1 + 2) 2 | Give a code snippet in #TI-89_BASIC
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
{\dis... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #Scheme | Scheme | (define (rot13 str)
(define (rot13-char c)
(integer->char (+ (char->integer c)
(cond ((and (char>=? c #\a) (char<? c #\n))
13)
((and (char>=? c #\A) (char<? c #\N))
13)
((and (ch... | Give a code snippet in #Scheme
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Babbage_problem | Babbage problem |
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Computers, second edition, 1970, p.... | #XPL0 | XPL0 | int N, C, R;
[C:= 0;
for N:= sqrt(269696) to -1>>1 do \to infinity (2^31-1)
if rem(N/10)=4 or rem(N/10)=6 then \must end 6: 4^2=16; 6^2=36
[R:= rem(N/100);
if R=14 or R=36 or R=64 or R=86 then \14^2=196, etc.
[R:= rem(N/1000);
if R=236 or R=264 or R=736 or R=76... | Give a code snippet in #XPL0
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Compu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Common_Lisp | Common Lisp | (defun roman-numeral (n)
(format nil "~@R" n)) | Give a code snippet in #Common_Lisp
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
... | #Maxima | Maxima | a: matrix([2, 9, 4], [7, 5, 3], [6, 1, 8])$
determinant(a);
-360
permanent(a);
900 | Give a code snippet in #Maxima
For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while ... | 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... | #Ring | Ring |
for n = 1 to 15
see catalan(n) + nl
next
func catalan n
if n = 0 return 1 ok
cat = 2 * (2 * n - 1) * catalan(n - 1) / (n + 1)
return cat
| Give a code snippet in #Ring
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/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #Raven | Raven | [ 'a' 'b' 'c' ] as $keys [ 1 2 3 ] as $vals
$keys $vals combine as $hash | Give a code snippet in #Raven
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Decode | Roman numerals/Decode | Task
Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer.
You don't need to validate the form of the Roman numeral.
Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately,
starting with the leftmost decima... | #Zoea_Visual | Zoea Visual |
#!/bin/zsh
function parseroman () {
local max=0 sum i j
local -A conv
conv=(I 1 V 5 X 10 L 50 C 100 D 500 M 1000)
for j in ${(Oas::)1}; do
i=conv[$j]
if (( i >= max )); then
(( sum+=i ))
(( max=i ))
else
(( sum-=i ))
fi
done
echo $sum
}
parseroman MCMXC
parseroman MMVII... | Give a code snippet in #Zoea_Visual
Task
Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer.
You don't need to validate the form of the Roman numeral.
Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separatel... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gray_code | Gray code | Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are many possible Gray codes. The follow... | #Liberty_BASIC | Liberty BASIC |
for r =0 to 31
print " Decimal "; using( "###", r); " is ";
B$ =dec2Bin$( r)
print " binary "; B$; ". Binary "; B$;
G$ =Bin2Gray$( dec2Bin$( r))
print " is "; G$; " in Gray code, or ";
B$ =Gray2Bin$( G$)
print B$; " in pure binary."
next r
end
... | Give a code snippet in #Liberty_BASIC
Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gaussian_elimination | Gaussian elimination | Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| #PHP | PHP | function swap_rows(&$a, &$b, $r1, $r2)
{
if ($r1 == $r2) return;
$tmp = $a[$r1];
$a[$r1] = $a[$r2];
$a[$r2] = $tmp;
$tmp = $b[$r1];
$b[$r1] = $b[$r2];
$b[$r2] = $tmp;
}
function gauss_eliminate($A, $b, $N)
{
for ($col = 0; $col < $N; $col++)
{
$j = $col;
$max = ... | Give a code snippet in #PHP
Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Jensen%27s_Device | Jensen's Device | Jensen's Device
You are encouraged to solve this task according to the task description, using any language you may know.
This task is an exercise in call by name.
Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the ALGOL 60 Report.
The following pr... | #Racket | Racket |
#lang algol60
begin
integer i;
real procedure sum (i, lo, hi, term);
value lo, hi;
integer i, lo, hi;
real term;
comment term is passed by-name, and so is i;
begin
real temp;
temp := 0;
for i := lo step 1 until hi do
temp := temp + term;
sum := temp
... | Give a code snippet in #Racket
Jensen's Device
You are encouraged to solve this task according to the task description, using any language you may know.
This task is an exercise in call by name.
Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the AL... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Red | Red | Red []
foreach line
split
{---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------} newline [
print reverse split line " "
]
| Give a code snippet in #Red
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces... | christopher/rosetta-code | |
http://rosettacode.org/wiki/9_billion_names_of_God_the_integer | 9 billion names of God the integer | This task is a variation of the short story by Arthur C. Clarke.
(Solvers should be aware of the consequences of completing this task.)
In detail, to specify what is meant by a “name”:
The integer 1 has 1 name “1”.
The integer 2 has 2 names “1+1”, and “2”.
The integer 3 has 3 names “1+1+1”, “2+1”, ... | #JavaScript | JavaScript |
(function () {
var cache = [
[1]
];
//this was never needed.
/* function PyRange(start, end, step) {
step = step || 1;
if (!end) {
end = start;
start = 0;
}
var arr = [];
for (var i = start; i < end; i += step) arr.push(i);
ret... | Give a code snippet in #JavaScript
This task is a variation of the short story by Arthur C. Clarke.
(Solvers should be aware of the consequences of completing this task.)
In detail, to specify what is meant by a “name”:
The integer 1 has 1 name “1”.
The integer 2 has 2 names “1+1”, and “2”.
The integer ... | 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... | #PHP | PHP |
// using bitwise and to check least significant digit
echo (2 & 1) ? 'odd' : 'even';
echo (3 & 1) ? 'odd' : 'even';
// using modulo
echo (3 % 2) ? 'odd' : 'even';
echo (4 % 2) ? 'odd' : 'even';
| Give a code snippet in #PHP
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/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Maude | Maude |
red 3 + 4 .
| Give a code snippet in #Maude
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separate... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #AutoHotkey | AutoHotkey | SetFormat, FloatFast, 0.15
While A_Index <= 1000
sum += 1/A_Index**2
MsgBox,% sum ;1.643934566681554 | Give a code snippet in #AutoHotkey
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Order_two_numerical_lists | Order two numerical lists | 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
She... | #Factor | Factor | IN: scratchpad { 2 3 } { 2 5 } before? .
t
| Give a code snippet in #Factor
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 |... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comments | Comments | Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| #Tern | Tern | :"THIS IS A COMMENT | Give a code snippet in #Tern
Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_multiples_of_3_and_5 | Sum multiples of 3 and 5 | Task
The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.
Show output for n = 1000.
This is is the same as Project Euler problem 1.
Extra credit: do this efficiently for n = 1e20 or higher.
| #Raku | Raku | sub sum35($n) { [+] grep * %% (3|5), ^$n; }
say sum35 1000; | Give a code snippet in #Raku
Task
The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.
Show output for n = 1000.
This is is the same as Project Euler problem 1.
Extra credit: do this efficiently for n = 1e20 or higher.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Linear_congruential_generator | Linear congruential generator | The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_{0}}
is a seed.
r
1
... | #C.2B.2B | C++ | #include <iostream>
//--------------------------------------------------------------------------------------------------
using namespace std;
//--------------------------------------------------------------------------------------------------
class mRND
{
public:
void seed( unsigned int s ) { _seed = s; }
pro... | Give a code snippet in #C.2B.2B
The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #Emacs_Lisp | Emacs Lisp | (let ((array [1 2 3 4 5]))
(apply #'+ (append array nil))
(apply #'* (append array nil))) | Give a code snippet in #Emacs_Lisp
Task
Compute the sum and product of an array of integers.
| 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... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const type: preferences is hash [string] array string;
const type: engaged is hash [string] string;
const func integer: pos (in array string: area, in string: searched) is func
result
var integer: pos is 1;
begin
while pos <= length(area) and area[pos] <> searched do
incr... | Give a code snippet in #Seed7
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 o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Solve_a_Hidato_puzzle | Solve a Hidato puzzle | The task is to write a program which solves Hidato (aka Hidoku) puzzles.
The rules are:
You are given a grid with some numbers placed in it. The other squares in the grid will be blank.
The grid is not necessarily rectangular.
The grid may have holes in it.
The grid is always connected.
The number “1” is always ... | #C.2B.2B | C++ |
#include <iostream>
#include <sstream>
#include <iterator>
#include <vector>
//------------------------------------------------------------------------------
using namespace std;
//------------------------------------------------------------------------------
struct node
{
int val;
unsigned char neighbors... | Give a code snippet in #C.2B.2B
The task is to write a program which solves Hidato (aka Hidoku) puzzles.
The rules are:
You are given a grid with some numbers placed in it. The other squares in the grid will be blank.
The grid is not necessarily rectangular.
The grid may have holes in it.
The grid is always conn... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would repr... | #Phix | Phix | function dot_product(sequence a, b)
return sum(sq_mul(a,b))
end function
function cross_product(sequence a, b)
integer {a1,a2,a3} = a, {b1,b2,b3} = b
return {a2*b3-a3*b2, a3*b1-a1*b3, a1*b2-a2*b1}
end function
function scalar_triple_product(sequence a, b, c)
return dot_product(a,cross_product(b,c))
end fu... | Give a code snippet in #Phix
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Output | Non-decimal radices/Output | Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routines of your programming langu... | #Go | Go | package main
import (
"fmt"
"math/big"
"strconv"
)
func main() {
// fmt.Print formats integer types directly as bases 2, 8, 10, and 16.
fmt.Printf("%b\n", 13)
fmt.Printf("%o\n", 13)
fmt.Printf("%d\n", 13)
fmt.Printf("%x\n", 13)
// big ints work with fmt as well.
d := big.NewI... | Give a code snippet in #Go
Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #SAS | SAS | data _null_;
s=0;
do n=1 to 1000;
s+1/n**2; /* s+x is synonym of s=s+x */
end;
e=s-constant('pi')**2/6;
put s e;
run; | Give a code snippet in #SAS
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Take_notes_on_the_command_line | Take notes on the command line | Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TXT followed by a newline.
Then al... | #Erlang | Erlang |
#! /usr/bin/env escript
main( Arguments ) ->
display_notes( Arguments ),
save_notes( Arguments ).
display_notes( [] ) -> io:fwrite( "~s", [erlang:binary_to_list(file_contents())] );
display_notes( _Arguments ) -> ok.
file() -> "NOTES.TXT".
file_contents() -> file_contents( file:read_file(file()) ).
fi... | Give a code snippet in #Erlang
Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TX... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Nested | Loops/Nested | Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.
Specifically, this task als... | #Quackery | Quackery | []
5 times
[ []
5 times [ 20 random 1+ join ]
nested join ]
dup say "Array contains:" cr
witheach
[ witheach
[ echo sp ]
cr ]
cr
say "Array up to item = 20:" cr
witheach
[ false swap
witheach
[ dup 20 = iff
[ drop not conclude ]
... | Give a code snippet in #Quackery
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Emirp_primes | Emirp primes | An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th emirp
In each list, the numbe... | #PL.2FI | PL/I | *process or(!);
pt1: Proc(run) Options(main);
/*********************************************************************
* 25.03.2014 Walter Pachl
* Note: Prime number computations are extended as needed
*********************************************************************/
Dcl debug Bit(1) Init('0'b);
Dcl run Char(... | Give a code snippet in #PL.2FI
An emirp (prime spelled backwards) are primes that when reversed (in their decimal representation) are a different prime.
(This rules out palindromic primes.)
Task
show the first twenty emirps
show all emirps between 7,700 and 8,000
show the 10,000th ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_calculator_algorithm | Parsing/RPN calculator algorithm | Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the RPN expression generated from the... | #Prolog | Prolog | rpn(L) :-
writeln('Token Action Stack'),
parse(L, [],[X] ,[]),
format('~nThe final output value is ~w~n', [X]).
% skip spaces
parse([X|L], St) -->
{char_type(X, white)},
parse(L, St).
% detect operators
parse([Op|L], [Y, X | St]) -->
{ is_op(Op, X, Y, V),
writef(' %s', [[Op]... | Give a code snippet in #Prolog
Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the R... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
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 |... | #Ksh | Ksh |
#!/bin/ksh
# Display a substring:
# - starting from n characters in and of m length;
# - starting from n characters in, up to the end of the string;
# - whole string minus the last character;
# - starting from a known character within the string and of m length;
# - starting from a known substring within th... | Give a code snippet in #Ksh
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
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_simple | Abbreviations, simple | The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backup 2 bottom 1 Cappend 2 change 1 ... | #Tcl | Tcl | proc appendCmd {word} {
# Procedure to append the correct command from the global list ::cmds
# for the word given as parameter to the global list ::result.
# If a matching word has been found and appended to ::result, this procedure
# behaves like a "continue" statement, causing the loop containing it to
# j... | Give a code snippet in #Tcl
The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backup 2 bo... | christopher/rosetta-code |
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