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/Old_lady_swallowed_a_fly | Old lady swallowed a fly | Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identical output.
Other tasks related to st... | #Scratch | Scratch | $ include "seed7_05.s7i";
const array array string: verses is [] (
[] ("fly", "I don't know why she swallowed the fly."),
[] ("spider", "That wriggled and jiggled and tickled inside her."),
[] ("bird", "Quite absurd. To swallow a bird."),
[] ("cat", "Fancy that. To swallow a cat."),
[] ("dog", "Wh... | Give a code snippet in #Scratch
Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identical outp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Naming_conventions | Naming conventions | Many languages have naming conventions regarding the identifiers used in the language, its libraries, and programs written in the language. Such conventions, which may be classified as de facto or de jure depending on how they are enforced,
often take the form of rules regarding prefixes, suffixes, and the use of upper... | #Python | Python | #lang racket
render-game-state
send-message-to-client
traverse-forest | Give a code snippet in #Python
Many languages have naming conventions regarding the identifiers used in the language, its libraries, and programs written in the language. Such conventions, which may be classified as de facto or de jure depending on how they are enforced,
often take the form of rules regarding prefixes... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Summarize_and_say_sequence | Summarize and say sequence | There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 311311222110 ...
The terms generat... | #Haskell | Haskell | import Data.Set (Set, member, insert, empty)
import Data.List (group, sort)
step :: String -> String
step = concatMap (\list -> show (length list) ++ [head list]) . group . sort
findCycle :: (Ord a) => [a] -> [a]
findCycle = aux empty where
aux set (x : xs)
| x `member` set = []
| otherwise = x : aux (insert x... | Give a code snippet in #Haskell
There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 31... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection 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
... | #uBasic.2F4tH | uBasic/4tH | PRINT "Selection sort:"
n = FUNC (_InitArray)
PROC _ShowArray (n)
PROC _Selectionsort (n)
PROC _ShowArray (n)
PRINT
END
_Selectionsort PARAM (1) ' Selection sort
LOCAL (3)
FOR b@ = 0 TO a@-1
c@ = b@
FOR d@ = b@ TO a@-1
IF @(d@) < @(c@) THEN c@ = d@
NEXT
IF b@ ... | Give a code snippet in #uBasic.2F4tH
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 |
Q... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers | Increasing gaps between consecutive Niven numbers | Note: Niven numbers are also called Harshad numbers.
They are also called multidigital numbers.
Niven numbers are positive integers which are evenly divisible by the sum of its
digits (expressed in base ten).
Evenly divisible means divisible with no remainder.
Task
find the gap (differen... | #Go | Go | package main
import "fmt"
type is func() uint64
func newSum() is {
var ms is
ms = func() uint64 {
ms = newSum()
return ms()
}
var msd, d uint64
return func() uint64 {
if d < 9 {
d++
} else {
d = 0
msd = ms()
}
... | Give a code snippet in #Go
Note: Niven numbers are also called Harshad numbers.
They are also called multidigital numbers.
Niven numbers are positive integers which are evenly divisible by the sum of its
digits (expressed in base ten).
Evenly divisible means divisible with no remainder.
Tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #Nanoquery | Nanoquery | import Nanoquery.Util
// a function to check if a year is a leap year
def isLeapYear(year)
if (year % 100 = 0)
return (year % 400 = 0)
else
return (year % 4 = 0)
end
end
// a function to format 1-digit numbers as "0x"
def form(num)
if (num > 9)
return str(num)
else
return "0" + str(num)
end
end
// g... | Give a code snippet in #Nanoquery
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variable_declaration_reset | Variable declaration reset | A decidely non-challenging task to highlight a potential difference between programming languages.
Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ... | #ALGOL_68 | ALGOL 68 | BEGIN
[]INT s = ( 1, 2, 2, 3, 4, 4, 5 );
FOR i FROM LWB s TO UPB s DO
INT curr := s[ i ], prev;
IF IF i > LWB s THEN curr = prev ELSE FALSE FI THEN
print( ( i, newline ) )
FI;
prev := curr
OD
END | Give a code snippet in #ALGOL_68
A decidely non-challenging task to highlight a potential difference between programming languages.
Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Image_convolution | Image convolution | One class of image digital filters is described by a rectangular matrix of real coefficients called kernel convoluted in a sliding window of image pixels. Usually the kernel is square
K
k
l
{\displaystyle K_{kl}}
, where k, l are in the range -R,-R+1,..,R-1,R. W=2R+1 is the kernel width. The filter determine... | #Octave | Octave | function [r, g, b] = rgbconv2(a, c)
r = im2uint8(mat2gray(conv2(a(:,:,1), c)));
g = im2uint8(mat2gray(conv2(a(:,:,2), c)));
b = im2uint8(mat2gray(conv2(a(:,:,3), c)));
endfunction
im = jpgread("Lenna100.jpg");
emboss = [-2, -1, 0;
-1, 1, 1;
0, 1, 2 ];
sobel = [-1., -2., -1.;
0., 0., 0.;
... | Give a code snippet in #Octave
One class of image digital filters is described by a rectangular matrix of real coefficients called kernel convoluted in a sliding window of image pixels. Usually the kernel is square
K
k
l
{\displaystyle K_{kl}}
, where k, l are in the range -R,-R+1,..,R-1,R. W=2R+1 is the ke... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Teacup_rim_text | Teacup rim text | On a set of coasters we have, there's a picture of a teacup. On the rim of the teacup the word TEA appears a number of times separated by bullet characters (•).
It occurred to me that if the bullet were removed and the words run together, you could start at any letter and still end up with a meaningful three... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | ClearAll[Teacuppable]
TeacuppableHelper[set_List] := Module[{f, s},
f = First[set];
s = StringRotateLeft[f, #] & /@ Range[Length[set]];
Sort[s] == Sort[set]
]
Teacuppable[set_List] := Module[{ss, l},
l = StringLength[First[set]];
ss = Subsets[set, {l}];
Select[ss, TeacuppableHelper]
]
s = Import["http:/... | Give a code snippet in #Mathematica.2FWolfram_Language
On a set of coasters we have, there's a picture of a teacup. On the rim of the teacup the word TEA appears a number of times separated by bullet characters (•).
It occurred to me that if the bullet were removed and the words run together, you could star... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Read_a_PPM_file | Bitmap/Read a PPM file | Using the data storage type defined on this page for raster images, read an image from a PPM file (binary P6 prefered).
(Read the definition of PPM file on Wikipedia.)
Task: Use write ppm file solution and grayscale image solution with this one in order to convert a color image to grayscale one.
| #M2000_Interpreter | M2000 Interpreter |
Module Checkit {
Function Bitmap {
If match("NN") then {
Read x as long, y as long
} else.if Match("N") Then {
\\ is a file?
Read f
if not Eof(f) then {
Line Input #f, p3$
... | Give a code snippet in #M2000_Interpreter
Using the data storage type defined on this page for raster images, read an image from a PPM file (binary P6 prefered).
(Read the definition of PPM file on Wikipedia.)
Task: Use write ppm file solution and grayscale image solution with this one in order to convert a color ima... | 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.
| #Wortel | Wortel | @sum [1 2 3 4] ; returns 10
@prod [1 2 3 4] ; returns 24 | Give a code snippet in #Wortel
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pick_random_element | Pick random element | Demonstrate how to pick a random element from a list.
| #Factor | Factor | ( scratchpad ) { "a" "b" "c" "d" "e" "f" } random .
"a" | Give a code snippet in #Factor
Demonstrate how to pick a random element from a list.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #AppleScript | AppleScript | on run
script
on |λ|(x)
script
on |λ|(y)
script
on |λ|(z)
if y ≠ z and 1 ≤ z and z ≤ 7 then
{{x, y, z} as string}
else
... | Give a code snippet in #AppleScript
There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be uniq... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Collections | Collections | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create a collection, and add a fe... | #Icon_and_Unicon | Icon and Unicon | # Creation of collections:
s := "abccd" # string, an ordered collection of characters, immutable
c := 'abcd' # cset, an unordered collection of characters, immutable
S := set() # set, an unordered collection of... | Give a code snippet in #Icon_and_Unicon
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
... | 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... | #JavaScript | JavaScript | #!/usr/bin/env js
function main() {
var wordList = read('unixdict.txt').split(/\s+/);
var anagrams = findAnagrams(wordList);
var derangedAnagrams = findDerangedAnagrams(anagrams);
var longestPair = findLongestDerangedPair(derangedAnagrams);
print(longestPair.join(' '));
}
function findLongestD... | Give a code snippet in #JavaScript
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/Knapsack_problem/Bounded | Knapsack problem/Bounded | A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature. So he needs some items during the trip. Food, clothing, etc. He has a good knapsack for carrying the things, but he knows that he can carry only 4 kg weight in his knapsack, because th... | #C.2B.2B | C++ | #include <iostream>
#include <vector>
#include <algorithm>
#include <stdexcept>
#include <memory>
#include <sys/time.h>
using std::cout;
using std::endl;
class StopTimer
{
public:
StopTimer(): begin_(getUsec()) {}
unsigned long long getTime() const { return getUsec() - begin_; }
private:
static unsigned... | Give a code snippet in #C.2B.2B
A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature. So he needs some items during the trip. Food, clothing, etc. He has a good knapsack for carrying the things, but he knows that he can carry only 4 kg w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Odd_word_problem | Odd word problem | Task
Write a program that solves the odd word problem with the restrictions given below.
Description
You are promised an input stream consisting of English letters and punctuations.
It is guaranteed that:
the words (sequence of consecutive letters) are delimited by one and only one punctuation,
the stream will... | #Phix | Phix | with javascript_semantics
string s = "what,is,the;meaning,of:life."
--string s = "we,are;not,in,kansas;any,more."
integer i = 0
function getchar()
i += 1
return s[i]
end function
function wrod(integer rev)
integer ch = getchar(), nch
-- integer ch = getc(0), nch
if not find(ch," .,:;!?") then
... | Give a code snippet in #Phix
Task
Write a program that solves the odd word problem with the restrictions given below.
Description
You are promised an input stream consisting of English letters and punctuations.
It is guaranteed that:
the words (sequence of consecutive letters) are delimited by one and only one... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tau_number | Tau number | A Tau number is a positive integer divisible by the count of its positive divisors.
Task
Show the first 100 Tau numbers.
The numbers shall be generated during run-time (i.e. the code may not contain string literals, sets/arrays of integers, or alike).
Related task
Tau function
| #Haskell | Haskell | tau :: Integral a => a -> a
tau n | n <= 0 = error "Not a positive integer"
tau n = go 0 (1, 1)
where
yo i = (i, i * i)
go r (i, ii)
| n < ii = r
| n == ii = r + 1
| 0 == mod n i = go (r + 2) (yo $ i + 1)
| otherwise = go r (yo $ i + 1)
isTau :: Integral a => a -> Bool
isTa... | Give a code snippet in #Haskell
A Tau number is a positive integer divisible by the count of its positive divisors.
Task
Show the first 100 Tau numbers.
The numbers shall be generated during run-time (i.e. the code may not contain string literals, sets/arrays of integers, or alike).
Related task
Tau functi... | 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
... | #SPAD | SPAD |
NNI ==> NonNegativeInteger
A:(NNI,NNI) -> NNI
A(m,n) ==
m=0 => n+1
m>0 and n=0 => A(m-1,1)
m>0 and n>0 => A(m-1,A(m,n-1))
-- Example
matrix [[A(i,j) for i in 0..3] for j in 0..3]
| Give a code snippet in #SPAD
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
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Define_a_primitive_data_type | Define a primitive data type | Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
| #Ruby | Ruby | Some object-oriented languages won't let you subclass the "basic" data types
like integers. Other languages implement those data types as classes, so you
can subclass them, no questions asked. Ruby implements numbers as classes
(Integer, with its concrete subclasses Fixnum and Bignum), and you can subclass
those classe... | Give a code snippet in #Ruby
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Time_a_function | Time a function | Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
between start and finish, which could ... | #JavaScript | JavaScript |
function test() {
let n = 0
for(let i = 0; i < 1000000; i++){
n += i
}
}
let start = new Date().valueOf()
test()
let end = new Date().valueOf()
console.log('test() took ' + ((end - start) / 1000) + ' seconds') // test() took 0.001 seconds
| Give a code snippet in #JavaScript
Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
be... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_output_device_is_a_terminal | Check output device is a terminal | Task
Demonstrate how to check whether the output device is a terminal or not.
Related task
Check input device is a terminal
| #Javascript.2FNodeJS | Javascript/NodeJS | node -p -e "Boolean(process.stdout.isTTY)"
true | Give a code snippet in #Javascript.2FNodeJS
Task
Demonstrate how to check whether the output device is a terminal or not.
Related task
Check input device is a terminal
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #SenseTalk | SenseTalk | findEulerSumOfPowers
to findEulerSumOfPowers
set MAX_NUMBER to 250
set possibleValues to 1..MAX_NUMBER
set possible5thPowers to each item of possibleValues to the power of 5
repeat for x0 in 1..250
repeat for x1 in 1..x0
repeat for x2 in 1..x1
repeat for x3 in 1..x2
... | Give a code snippet in #SenseTalk
There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth pow... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_quadratic_function | Roots of a quadratic 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.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your program must correctly handle n... | #Forth | Forth | : quadratic ( fa fb fc -- r1 r2 )
frot frot
( c a b )
fover 3 fpick f* -4e f* fover fdup f* f+
( c a b det )
fdup f0< if abort" imaginary roots" then
fsqrt
fover f0< if fnegate then
f+ fnegate
( c a b-det )
2e f/ fover f/
( c a r1 )
frot frot f/ fover f/ ; | Give a code snippet in #Forth
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Burrows%E2%80%93Wheeler_transform | Burrows–Wheeler transform |
This page uses content from Wikipedia. The original article was at Burrows–Wheeler_transform. 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 Burrows–Wheeler transform (BWT, also called block-s... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.Linq;
namespace BurrowsWheeler {
class Program {
const char STX = (char)0x02;
const char ETX = (char)0x03;
private static void Rotate(ref char[] a) {
char t = a.Last();
for (int i = a.Length - 1; i > 0; ... | Give a code snippet in #C.23
This page uses content from Wikipedia. The original article was at Burrows–Wheeler_transform. 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 Burrows–Wheeler trans... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_angle | Averages/Mean angle | When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first reading was of 350 degrees and the ... | #11l | 11l | F mean_angle(angles)
V x = sum(angles.map(a -> cos(radians(a)))) / angles.len
V y = sum(angles.map(a -> sin(radians(a)))) / angles.len
R degrees(atan2(y, x))
print(mean_angle([350, 10]))
print(mean_angle([90, 180, 270, 360]))
print(mean_angle([10, 20, 30])) | Give a code snippet in #11l
When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first readin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Collections | Collections | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create a collection, and add a fe... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
enable_output(set of string);
const proc: main is func
local
var set of string: aSet is {"iron", "copper"};
begin
writeln(aSet);
incl(aSet, "silver");
writeln(aSet);
end func; | Give a code snippet in #Seed7
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Cr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Langton%27s_ant | Langton's ant | Langton's ant is a cellular automaton that models an ant sitting on a plane of cells, all of which are white initially, the ant facing in one of four directions.
Each cell can either be black or white.
The ant moves according to the color of the cell it is currently sitting in, with the following rules:
If the ce... | #Ring | Ring |
load "guilib.ring"
load "stdlib.ring"
new qapp
{
win1 = new qwidget() {
setwindowtitle("drawing using qpainter")
setgeometry(100,100,500,500)
label1 = new qlabel(win1) {
setgeometry(10,10,400,400)
... | Give a code snippet in #Ring
Langton's ant is a cellular automaton that models an ant sitting on a plane of cells, all of which are white initially, the ant facing in one of four directions.
Each cell can either be black or white.
The ant moves according to the color of the cell it is currently sitting in, with the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial_base_numbers_indexing_permutations_of_a_collection | Factorial base numbers indexing permutations of a collection | You need a random arrangement of a deck of cards, you are sick of lame ways of doing this. This task is a super-cool way of doing this using factorial base numbers.
The first 25 factorial base numbers in increasing order are: 0.0.0, 0.0.1, 0.1.0, 0.1.1, 0.2.0, 0.2.1, 1.0.0, 1.0.1, 1.1.0, 1.1.1,1.2.0, 1.2.1, 2.0.0, 2.0.... | #Factor | Factor | USING: assocs io kernel literals math math.factorials
math.parser math.ranges prettyprint qw random sequences
splitting ;
RENAME: factoradic math.combinatorics.private => _factoradic
RENAME: rotate sequences.extras => _rotate
IN: rosetta-code.factorial-permutations
CONSTANT: shoe $[
qw{ A K Q J 10 9 8 7 6 5 4 3 2... | Give a code snippet in #Factor
You need a random arrangement of a deck of cards, you are sick of lame ways of doing this. This task is a super-cool way of doing this using factorial base numbers.
The first 25 factorial base numbers in increasing order are: 0.0.0, 0.0.1, 0.1.0, 0.1.1, 0.2.0, 0.2.1, 1.0.0, 1.0.1, 1.1.0,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/AKS_test_for_primes | AKS test for primes | The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the coefficients of the polynomial ... | #Objeck | Objeck | class AksTest {
@c : static : Int[];
function : Main(args : String[]) ~ Nil {
@c := Int->New[100];
for(n := 0; n < 10; n++;) {
Coef(n);
"(x-1)^ {$n} = "->Print();
Show(n);
'\n'->Print();
};
"\nPrimes:"->PrintLine();
for(n := 2; n <= 63; n++;) {
if(IsPrime(n)) ... | Give a code snippet in #Objeck
The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the... | 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... | #F.23 | F# | for i in 2..2..8 do
printf "%d, " i
printfn "done" | Give a code snippet in #F.23
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/Incr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Collections | Collections | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create a collection, and add a fe... | #V | V | [4 3 2 1] 5 swap cons
=[5 4 3 2 1] | Give a code snippet in #V
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_lines_from_a_file | Remove lines from a file | Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from th... | #Racket | Racket |
#lang racket
(define (remove-lines file from num)
(define lines (file->lines file))
(define-values [pfx rest] (split-at lines (sub1 from)))
(display-lines-to-file (append pfx (drop rest num)) file #:exists 'replace))
| Give a code snippet in #Racket
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sudoku | Sudoku | Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| #Scala | Scala | object SudokuSolver extends App {
class Solver {
var solution = new Array[Int](81) //listOfFields toArray
val fp2m: Int => Tuple2[Int,Int] = pos => Pair(pos/9+1,pos%9+1) //get row, col from array position
val setAll = (1 to 9) toSet //all possibilities
val arrayGroups = new Array[List[List[I... | Give a code snippet in #Scala
Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| 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.
| #Rust | Rust |
extern crate rug;
use rug::Integer;
use rug::ops::Pow;
fn main() {
for i in [3, 20, 100, 1_000].iter() {
let ten = Integer::from(10);
let mut limit = Integer::from(Integer::from(&ten.pow(*i as u32)) - 1);
let mut aux_3_1 = &limit.mod_u(3u32);
let mut aux_3_2 = Integer::from(&li... | Give a code snippet in #Rust
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/Knuth_shuffle | Knuth shuffle | The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 to last, the algorithm can be d... | #Fortran | Fortran | program Knuth_Shuffle
implicit none
integer, parameter :: reps = 1000000
integer :: i, n
integer, dimension(10) :: a, bins = 0, initial = (/ (n, n=1,10) /)
do i = 1, reps
a = initial
call Shuffle(a)
where (a == initial) bins = bins + 1 ! skew tester
end do
write(*, "(10(i8))") bins
! print... | Give a code snippet in #Fortran
The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from ... | 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
| #Dao | Dao | io.writeln( 'Hello world!' ) | Give a code snippet in #Dao
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
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #Elena | Elena | import system'routines;
import extensions;
import extensions'routines;
import extensions'text;
extension bottleOp
{
bottleDescription()
= self.toPrintable() + (self != 1).iif(" bottles"," bottle");
bottleEnumerator() = new Variable(self).doWith:(n)
{
^ new Enumerator
{
... | Give a code snippet in #Elena
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98... | 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 ... | #Fortran | Fortran |
program mean_time_of_day
implicit none
integer(kind=4), parameter :: dp = kind(0.0d0)
type time_t
integer(kind=4) :: hours, minutes, seconds
end type
character(len=8), dimension(4), parameter :: times = &
(/ '23:00:17', '23:40:20', '00:12:45', '00:17:19' /)
real(kind=dp), dimension(size(times)... | Give a code snippet in #Fortran
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 idea... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points | Circles of given radius through two points |
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points.
Exceptions
r==0.0 should be treated as never describing circles (except in the case where the points are coincident).
If the points are coincident then an infinite number of circles with the point on thei... | #Tcl | Tcl | proc findCircles {p1 p2 r} {
lassign $p1 x1 y1
lassign $p2 x2 y2
# Special case: coincident & zero size
if {$x1 == $x2 && $y1 == $y2 && $r == 0.0} {
return [list [list $x1 $y1 0.0]]
}
if {$r <= 0.0} {
error "radius must be positive for sane results"
}
if {$x1 == $x2 && $y1 == $y2} {
e... | Give a code snippet in #Tcl
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points.
Exceptions
r==0.0 should be treated as never describing circles (except in the case where the points are coincident).
If the points are coincident then an infinite number of c... | 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 ... | #Lasso | Lasso | define stderr(s::string) => {
file_stderr->writeBytes(#s->asBytes)
}
stderr('Goodbye, World!') | Give a code snippet in #Lasso
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/String_matching | String matching |
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 |... | #AutoIt | AutoIt | $string1 = "arduinoardblobard"
$string2 = "ard"
; == Determining if the first string starts with second string
If StringLeft($string1, StringLen($string2)) = $string2 Then
ConsoleWrite("1st string starts with 2nd string." & @CRLF)
Else
ConsoleWrite("1st string does'nt starts with 2nd string." & @CRLF)
EndIf
; == ... | Give a code snippet in #AutoIt
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_literals,_with_continuations | Long literals, with continuations | This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The literal is to be in the form ... | #Crystal | Crystal | require "time"
last_revision = Time.utc year: 2021, month: 2, day: 25
# the `%w()` literal creates an array from a whitespace-delimited string literal
# it's equivalent to %(string literal).split
# https://crystal-lang.org/reference/syntax_and_semantics/literals/string.html
element_list : Array(String) = %w(
hydrog... | Give a code snippet in #Crystal
This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pangram_checker | Pangram checker | Pangram checker
You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.
For example: The quick brown fox jumps over the lazy dog.
Task
Write a function or method to chec... | #Java | Java | public class Pangram {
public static boolean isPangram(String test){
for (char a = 'A'; a <= 'Z'; a++)
if ((test.indexOf(a) < 0) && (test.indexOf((char)(a + 32)) < 0))
return false;
return true;
}
public static void main(String[] args){
System.out.printl... | Give a code snippet in #Java
Pangram checker
You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.
For example: The quick brown fox jumps over the lazy dog.
Task
Writ... | 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... | #Julia | Julia | stack = Int[] # []
@show push!(stack, 1) # [1]
@show push!(stack, 2) # [1, 2]
@show push!(stack, 3) # [1, 2, 3]
@show pop!(stack) # 3
@show length(stack) # 2
@show empty!(stack) # []
@show isempty(stack) # true | Give a code snippet in #Julia
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 ac... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | maxit = 13;
maxitj = 10;
a1 = 1.0;
a2 = 0.0;
d1 = 3.2;
a = 0.0;
Table[
a = a1 + (a1 - a2)/d1;
Do[
x = 0.0;
y = 0.0;
Do[
y = 1.0 - 2.0 y x;
x = a - x x;
,
{k, 1, 2^i}
];
a = a - x/y
,
{j, maxitj}
];
d = (a1 - a2)/(a - a1);
d1 = d;
a2 = a1;
a1 = a;
{i, d}
,
{i, 2... | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| 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.)
| #Intercal | Intercal | PLEASE NOTE This is a comment | Give a code snippet in #Intercal
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/Arithmetic-geometric_mean | Arithmetic-geometric mean |
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Write a function to compute the arithmetic-geomet... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | PrecisionDigits = 85;
AGMean[a_, b_] := FixedPoint[{ Tr@#/2, Sqrt[Times@@#] }&, N[{a,b}, PrecisionDigits]]〚1〛 | Give a code snippet in #Mathematica.2FWolfram_Language
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bulls_and_cows/Player | Bulls and cows/Player | Task
Write a player of the Bulls and Cows game, rather than a scorer. The player should give intermediate answers that respect the scores to previous attempts.
One method is to generate a list of all possible numbers that could be the answer, then to prune the list by keeping only those numbers that would give an equ... | #SenseTalk | SenseTalk | set the remoteWorkInterval to .001 -- optional
repeat forever
repeat forever
set description to "Enter a 4 digit number" & newline & "- zero's excluded" & newline & "- each digit should be unique" & newline
Ask "Enter a Number" title "Bulls & Cows (Player)" message description
put it into num
if num is ""
A... | Give a code snippet in #SenseTalk
Task
Write a player of the Bulls and Cows game, rather than a scorer. The player should give intermediate answers that respect the scores to previous attempts.
One method is to generate a list of all possible numbers that could be the answer, then to prune the list by keeping only t... | 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 ... | #jq | jq | jq -n —-arg s 'Goodbye, World!' '$s | stderr | empty' | Give a code snippet in #jq
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/Sorting_algorithms/Cocktail_sort | Sorting algorithms/Cocktail 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
... | #BBC_BASIC | BBC BASIC | DEF PROC_ShakerSort(Size%)
Start%=2
End%=Size%
Direction%=1
LastChange%=1
REPEAT
FOR J% = Start% TO End% STEP Direction%
IF data%(J%-1) > data%(J%) THEN
SWAP data%(J%-1),data%(J%)
LastChange% = J%
ENDIF
NEXT J%
End% = Start%
Start% = LastChange% - Direction%
Direction% = Direction% * -... | Give a code snippet in #BBC_BASIC
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 |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Groovy | Groovy | rnd = new Random()
result = (1..1000).inject([]) { r, i -> r << rnd.nextGaussian() } | Give a code snippet in #Groovy
Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Relate... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Levenshtein_distance | Levenshtein distance |
This page uses content from Wikipedia. The original article was at Levenshtein distance. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In information theory and computer science, the Levenshtein ... | #PicoLisp | PicoLisp | (de levenshtein (A B)
(let D
(cons
(range 0 (length A))
(mapcar
'((I) (cons I (copy A)))
(range 1 (length B)) ) )
(for (J . Y) B
(for (I . X) A
(set
(nth D (inc J) (inc I))
(if (= X Y)
(get D J ... | Give a code snippet in #PicoLisp
This page uses content from Wikipedia. The original article was at Levenshtein distance. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In information theory and ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mandelbrot_set | Mandelbrot set | Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| #Swift | Swift | import Foundation
import Numerics
import QDBMP
public typealias Color = (red: UInt8, green: UInt8, blue: UInt8)
public class BitmapDrawer {
public let imageHeight: Int
public let imageWidth: Int
var grid: [[Color?]]
private let bmp: OpaquePointer
public init(height: Int, width: Int) {
self.image... | Give a code snippet in #Swift
Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #Scheme | Scheme | (define (me-errors xx exception)
(if (even? xx)
xx
(exception)))
;example that does nothing special on exception
(call/cc
(lambda (exception)
(me-errors 222 exception)
(display "I guess everything is alright")))
;example that laments oddness on exception
(call/cc
(lambda (all-ok) ;used t... | Give a code snippet in #Scheme
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exception... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Heapsort | Sorting algorithms/Heapsort |
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
... | #Racket | Racket |
#lang racket
(require (only-in srfi/43 vector-swap!))
(define (heap-sort! xs)
(define (ref i) (vector-ref xs i))
(define (swap! i j) (vector-swap! xs i j))
(define size (vector-length xs))
(define (sift-down! r end)
(define c (+ (* 2 r) 1))
(define c+1 (+ c 1))
(when (<= c end)
(define c... | Give a code snippet in #Racket
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/Compiler/AST_interpreter | Compiler/AST interpreter | An AST interpreter interprets an Abstract Syntax Tree (AST)
produced by a Syntax Analyzer.
Task[edit]
Take the AST output from the Syntax analyzer task, and interpret it as appropriate.
Refer to the Syntax analyzer task for details of the AST.
Loading the AST from the syntax analyzer is as simple as (pseudo code)
de... | #zkl | zkl | const{ var _n=-1; var[proxy]N=fcn{ _n+=1 }; } // enumerator
const FETCH=N, STORE=N, PUSH=N, ADD=N, SUB=N, MUL=N, DIV=N, MOD=N,
LT=N, GT=N, LE=N, GE=N, EQ=N, NE=N,
AND=N, OR=N, NEG=N, NOT=N,
JMP=N, JZ=N, PRTC=N, PRTS=N, PRTI=N, HALT=N;
const nd_String=N, nd_Sequence=N, nd_If... | Give a code snippet in #zkl
An AST interpreter interprets an Abstract Syntax Tree (AST)
produced by a Syntax Analyzer.
Task[edit]
Take the AST output from the Syntax analyzer task, and interpret it as appropriate.
Refer to the Syntax analyzer task for details of the AST.
Loading the AST from the syntax analyzer is a... | 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... | #Octave | Octave | for (n = 1:20)
printf ("%i: ", n)
printf ("%i ", factor (n))
printf ("\n")
endfor | Give a code snippet in #Octave
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 woul... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_nth_number_with_exactly_n_divisors | Sequence: nth number with exactly n divisors | Calculate the sequence where each term an is the nth that has n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A073916
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: smallest number with exactly n divisors | #Sidef | Sidef | func f(n {.is_prime}) {
n.prime**(n-1)
}
func f(n) {
n.th { .sigma0 == n }
}
say 20.of { f(_+1) } | Give a code snippet in #Sidef
Calculate the sequence where each term an is the nth that has n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A073916
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: smallest number... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Password_generator | Password generator | Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-./:;<=>?@[]^_{|}~
(the above ch... | #Arturo | Arturo | lowercase: `a`..`z`
uppercase: `A`..`Z`
digits: `0`..`9`
other: map split "!\"#$%&'()*+,-./:;<=>?@[]^_{|}~" => [to :char]
any: lowercase ++ uppercase ++ digits ++ other
generate: function [length][
if length < 4 [
print (color #red "ERROR: ") ++ "password length too short"
exit
]
chars... | Give a code snippet in #Arturo
Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animation | Animation |
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task demonstrates this.
Task
Creat... | #REBOL | REBOL | rebol [
Title: "Basic Animation"
URL: http://rosettacode.org/wiki/Basic_Animation
]
message: "Hello World! " how: 1
roll: func [
"Shifts a text string right or left by one character."
text [string!] "Text to shift."
direction [integer!] "Direction to shift -- right: 1, left: -1."
/local h t
][
either direct... | Give a code snippet in #REBOL
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task de... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rate_counter | Rate counter | Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus.
Multiple approaches are allowed (even preferable), so long as they can accomplish these goals:
Run N seconds worth... | #Kotlin | Kotlin | // version 1.1.3
typealias Func<T> = (T) -> T
fun cube(n: Int) = n * n * n
fun <T> benchmark(n: Int, func: Func<T>, arg: T): LongArray {
val times = LongArray(n)
for (i in 0 until n) {
val m = System.nanoTime()
func(arg)
times[i] = System.nanoTime() - m
}
return times
} ... | Give a code snippet in #Kotlin
Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus.
Multiple approaches are allowed (even preferable), so long as they can accomplish th... | 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
| #Racket | Racket |
#lang racket
(for/sum ([x #(3 1 4 1 5 9)]) (* x x))
| Give a code snippet in #Racket
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/Abbreviations,_easy | Abbreviations, easy | This task is an easier (to code) variant of the Rosetta Code task: Abbreviations, simple.
For this task, the following command table will be used:
Add ALTer BAckup Bottom CAppend Change SCHANGE CInsert CLAst COMPress COpy
COUnt COVerlay CURsor DELete CDelete Down DUPlicate Xedit EXPand EXTract Find
... | #Ruby | Ruby | #!/usr/bin/env ruby
cmd_table = File.read(ARGV[0]).split
user_str = File.read(ARGV[1]).split
user_str.each do |abbr|
candidate = cmd_table.find do |cmd|
cmd.count('A-Z') <= abbr.length && abbr.casecmp(cmd[0...abbr.length]).zero?
end
print candidate.nil? ? '*error*' : candidate.upcase
print ' '
end
... | Give a code snippet in #Ruby
This task is an easier (to code) variant of the Rosetta Code task: Abbreviations, simple.
For this task, the following command table will be used:
Add ALTer BAckup Bottom CAppend Change SCHANGE CInsert CLAst COMPress COpy
COUnt COVerlay CURsor DELete CDelete Down DUPlic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Polynomial_long_division | Polynomial long division |
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In algebra, polynomial long division is an algorithm for d... | #Wren | Wren | import "/dynamic" for Tuple
var Solution = Tuple.create("Solution", ["quotient", "remainder"])
var polyDegree = Fn.new { |p|
for (i in p.count-1..0) if (p[i] != 0) return i
return -2.pow(31)
}
var polyShiftRight = Fn.new { |p, places|
if (places <= 0) return p
var pd = polyDegree.call(p)
if (p... | Give a code snippet in #Wren
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In algebra, polynomial long ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Count_examples | Rosetta Code/Count examples | task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll need to use the Media Wiki AP... | #Nim | Nim | import httpclient, strutils, xmltree, xmlparser, cgi
proc count(s, sub: string): int =
var i = 0
while true:
i = s.find(sub, i)
if i < 0: break
inc i
inc result
const
mainSite = "http://www.rosettacode.org/mw/api.php?action=query&list=categorymembers&cmtitle=Category:Programming_Tasks&cmlimit=... | Give a code snippet in #Nim
task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size_distribution | File size distribution | Task
Beginning from the current directory, or optionally from a directory specified as a command-line argument, determine how many files there are of various sizes in a directory hierarchy.
My suggestion is to sort by logarithmn of file size, since a few bytes here or there, or even a factor of two or three, may no... | #Haskell | Haskell | {-# LANGUAGE LambdaCase #-}
import Control.Concurrent (forkIO, setNumCapabilities)
import Control.Concurrent.Chan (Chan, newChan, readChan,
writeChan, writeList2Chan)
import Control.Exception (IOException, catch)
import... | Give a code snippet in #Haskell
Task
Beginning from the current directory, or optionally from a directory specified as a command-line argument, determine how many files there are of various sizes in a directory hierarchy.
My suggestion is to sort by logarithmn of file size, since a few bytes here or there, or even... | 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.)
| #Simula | Simula | COMMENT This is a comment for Simula 67; | Give a code snippet in #Simula
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/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... | #AutoHotkey | AutoHotkey | #NoEnv
; Set the floating-point precision
SetFormat, Float, 0.15
; Super-global variables for function objects
Global F, G
; User-defined functions
Cube(X) {
Return X ** 3
}
CubeRoot(X) {
Return X ** (1/3)
}
; Function arrays, Sin/ASin and Cos/ACos are built-in
FuncArray1 := [Func("Sin"), Func("Cos"), Func("Cub... | Give a code snippet in #AutoHotkey
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 ot... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #Wart | Wart | def (dedup l)
let exists (table)
collect+each x l
unless exists.x
yield x
exists.x <- 1 | Give a code snippet in #Wart
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Objeck | Objeck |
bundle Default {
class ReadFile {
function : Main(args : String[]) ~ Nil {
f := IO.FileReader->New("in.txt");
if(f->IsOpen()) {
string := f->ReadString();
while(f->IsEOF() = false) {
string->PrintLine();
string := f->ReadString();
};
f->Close();
... | Give a code snippet in #Objeck
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| 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... | #Modula-2 | Modula-2 |
MODULE ReverseWords;
FROM STextIO IMPORT
WriteString, WriteLn;
FROM Strings IMPORT
Assign, Concat, Append;
CONST
NL = CHR(10);
Sp = ' ';
Txt = "---------- Ice and Fire -----------" + NL +
NL +
"fire, in end will world the say Some" + NL +
"ice. in say Some" + NL +
"desire of tasted I've ... | Give a code snippet in #Modula-2
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 s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Additive_primes | Additive primes | Definitions
In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes.
Task
Write a program to determine (and show here) all additive primes less than 500.
Optionally, show the number of additive primes.
Also see
the OEIS entry: A046704 additive primes.
... | #C.2B.2B | C++ | #include <iomanip>
#include <iostream>
bool is_prime(unsigned int n) {
if (n < 2)
return false;
if (n % 2 == 0)
return n == 2;
if (n % 3 == 0)
return n == 3;
for (unsigned int p = 5; p * p <= n; p += 4) {
if (n % p == 0)
return false;
p += 2;
... | Give a code snippet in #C.2B.2B
Definitions
In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes.
Task
Write a program to determine (and show here) all additive primes less than 500.
Optionally, show the number of additive primes.
Also see
the OEIS entr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/Integer | Literals/Integer | Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Task
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods, but should be interpreted by the compiler or... | #Clojure | Clojure | user=> 2r1001
9
user=> 8r64
52
user=> 064
52
user=> 16r4b
75
user=> 0x4b
75
user=> | Give a code snippet in #Clojure
Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Task
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods, but should ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generic_swap | Generic swap | Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides genericity.
If variables are typed in t... | #68000_Assembly | 68000 Assembly | EXG D0,D1 ;swap the contents of D0 and D1
EXG A0,A1 ;swap the contents of A0 and A1 | Give a code snippet in #68000_Assembly
Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leap_year | Leap year | Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| #Lasso | Lasso | define isLeapYear(y::integer) => {
#y % 400 == 0 ? return true
#y % 100 == 0 ? return false
#y % 4 == 0 ? return true
return false
}
with test in array(2012,2016,1933,1900,1999,2000) do => {^
isLeapYear(#test)
'\r'
^} | Give a code snippet in #Lasso
Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for ... | #Common_Lisp | Common Lisp |
(defvar ♥♦♣♠ "♥♦♣♠")
(defun ✈ () "a plane unicode function")
| Give a code snippet in #Common_Lisp
As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file | Bitmap/Write a PPM file | Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered).
(Read the definition of PPM file on Wikipedia.)
| #Phix | Phix | -- demo\rosetta\Bitmap_write_ppm.exw
constant dimx = 512, dimy = 512
constant fn = open("first.ppm","wb") -- b - binary mode
sequence color
printf(fn, "P6\n%d %d\n255\n", {dimx,dimy})
for y=0 to dimy-1 do
for x=0 to dimx-1 do
color = {remainder(x,256), -- red
remainder(y,256), -- green
... | Give a code snippet in #Phix
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered).
(Read the definition of PPM file on Wikipedia.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/String_comparison | String comparison |
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 |... | #Scheme | Scheme |
;; Comparing two strings for exact equality
(string=? "hello" "hello")
;; Comparing two strings for inequality
(not (string=? "hello" "Hello"))
;; Checking if the first string is lexically ordered before the second
(string<? "bar" "foo")
;; Checking if the first string is lexically ordered after the second
(st... | Give a code snippet in #Scheme
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Resistor_mesh | Resistor mesh |
Task
Given 10×10 grid nodes (as shown in the image) interconnected by 1Ω resistors as shown,
find the resistance between points A and B.
See also
(humor, nerd sniping) xkcd.com cartoon
| #Euler_Math_Toolbox | Euler Math Toolbox |
>load incidence;
>{u,r}=solvePotentialX(makeRectangleX(10,10),12,68); r,
1.60899124173
| Give a code snippet in #Euler_Math_Toolbox
Task
Given 10×10 grid nodes (as shown in the image) interconnected by 1Ω resistors as shown,
find the resistance between points A and B.
See also
(humor, nerd sniping) xkcd.com cartoon
| 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... | #D.C3.A9j.C3.A0_Vu | Déjà Vu | local :open-doors [ rep 101 false ]
for i range 1 100:
local :j i
while <= j 100:
set-to open-doors j not open-doors! j
set :j + j i
!print\ "Open doors: "
for i range 1 100:
if open-doors! i:
!print\( to-str i " " ) | Give a code snippet in #D.C3.A9j.C3.A0_Vu
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Playfair_cipher | Playfair cipher | Playfair cipher
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Implement a Playfair cipher for encryption and decryption.
The user must be able to choose J = I or no Q in the alphabet.
The output of the encrypted and decrypted message ... | #Julia | Julia | function playfair(key, txt, isencode=true, from = "J", to = "")
to = (to == "" && from == "J") ? "I" : to
function canonical(s, dup_toX=true)
s = replace(replace(uppercase(s), from => to), r"[^A-Z]" => "")
a, dupcount = [c for c in s], 0
for i in 1:2:length(a)-1
if s[i] == ... | Give a code snippet in #Julia
Playfair cipher
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Implement a Playfair cipher for encryption and decryption.
The user must be able to choose J = I or no Q in the alphabet.
The output of the e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Include_a_file | Include a file | Task
Demonstrate the language's ability to include source code from other files.
See Also
Compiler/Simple file inclusion pre processor
| #Maxima | Maxima | load("c:/.../source.mac")$
/* or if source.mac is in Maxima search path (see ??file_search_maxima), simply */
load(source)$ | Give a code snippet in #Maxima
Task
Demonstrate the language's ability to include source code from other files.
See Also
Compiler/Simple file inclusion pre processor
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #Quackery | Quackery | [ over 3 < if [ 1 - ]
dup 4 / over +
over 100 / -
swap 400 / +
swap 1 -
[ table
0 3 2 5 0 3
5 1 4 6 2 4 ]
+ + 7 mod ] is dayofweek ( day month year --> weekday )
[ dup 400 mod 0 = iff
[ drop true ] done
dup 100 mod 0 = iff
[ drop false ] ... | Give a code snippet in #Quackery
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pig_the_dice_game | Pig the dice game | The game of Pig is a multiplayer game played with a single six-sided die. The
object of the game is to reach 100 points or more.
Play is taken in turns. On each person's turn that person has the option of either:
Rolling the dice: where a roll of two to six is added to their score for that turn and th... | #Eiffel | Eiffel |
class
PLAYER
create
set_name
feature
set_name(n:STRING)
do
name := n.twin
set_points(0)
end
strategy(cur_points:INTEGER)
local
current_points, thrown:INTEGER
do
io.put_string ("You currently have " +points.out+". %NDo you want to save your points? Press y or n.%N")
io.read_line
if io.l... | Give a code snippet in #Eiffel
The game of Pig is a multiplayer game played with a single six-sided die. The
object of the game is to reach 100 points or more.
Play is taken in turns. On each person's turn that person has the option of either:
Rolling the dice: where a roll of two to six is added to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evaluate_binomial_coefficients | Evaluate binomial coefficients | This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
)
…
(
n
−
k
+
1
)
k
(
k
−
1... | #AppleScript | AppleScript | set n to 5
set k to 3
on calculateFactorial(val)
set partial_factorial to 1 as integer
repeat with i from 1 to val
set factorial to i * partial_factorial
set partial_factorial to factorial
end repeat
return factorial
end calculateFactorial
set n_factorial to calculateFactorial(n)
set k_factorial to calculat... | Give a code snippet in #AppleScript
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
... | 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... | #J | J | NB. knight moves for each square of a (y,y) board
kmoves=: monad define
t=. (>,{;~i.y) +"1/ _2]\2 1 2 _1 1 2 1 _2 _1 2 _1 _2 _2 1 _2 _1
(*./"1 t e. i.y) <@#"1 y#.t
)
ktourw=: monad define
M=. >kmoves y
p=. k=. 0
b=. 1 $~ *:y
for. i.<:*:y do.
b=. 0 k}b
p=. p,k=. ((i.<./) +/"1 b{~j{M){j=. ({&b # ]) k{M
end.... | Give a code snippet in #J
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"; tha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #MAXScript | MAXScript |
rand = random 1 10
clearListener()
while true do
(
userval = getKBValue prompt:"Enter an integer between 1 and 10: "
if userval == rand do (format "\nWell guessed!\n"; exit)
format "\nChoose another value\n"
)
| Give a code snippet in #MAXScript
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conditional_structures | Conditional structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common conditional structures include ... | #Deluge | Deluge | if (input.Field == "Hello World") {
sVar = "good";
} else if (input.Field == "Bye World") {
sVar = "bad";
} else {
sVar = "neutral";
} | Give a code snippet in #Deluge
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common... | 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
... | #Sidef | Sidef | func in_order(a) {
return true if (a.len <= 1);
var first = a[0];
a.ft(1).all { |elem| first <= elem ? do { first = elem; true } : false }
}
func bogosort(a) {
a.shuffle! while !in_order(a);
return a;
}
var arr = 5.of{ 100.rand.int };
say "Before: #{arr}";
say "After: #{bogosort(arr)}"; | Give a code snippet in #Sidef
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/N-queens_problem | N-queens problem |
Solve the eight queens puzzle.
You can extend the problem to solve the puzzle with a board of size NxN.
For the number of solutions for small values of N, see OEIS: A000170.
Related tasks
A* search algorithm
Solve a Hidato puzzle
Solve a Holy Knight's tour
Knight's tour
Peaceful chess queen armie... | #Arturo | Arturo | result: new []
queens: function [n, i, a, b, c][
if? i < n [
loop 1..n 'j [
if all? @[
not? contains? a j
not? contains? b i+j
not? contains? c i-j
] ->
queens n, i+1, a ++ @[j], b ++ @[i+j], c ++ @[i-j]
]
... | Give a code snippet in #Arturo
Solve the eight queens puzzle.
You can extend the problem to solve the puzzle with a board of size NxN.
For the number of solutions for small values of N, see OEIS: A000170.
Related tasks
A* search algorithm
Solve a Hidato puzzle
Solve a Holy Knight's tour
Knight's ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program defList.s */
/* Constantes */
.equ STDOUT, 1 @ Linux output console
.equ EXIT, 1 @ Linux syscall
.equ READ, 3
.equ WRITE, 4
.equ NBELEMENTS, 100 @ list size
/***************************... | Give a code snippet in #ARM_Assembly
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Elem... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_exponentiation | Modular exponentiation | Find the last 40 decimal digits of
a
b
{\displaystyle a^{b}}
, where
a
=
2988348162058574136915891421498819466320163312926952423791023078876139
{\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139}
b
=
235139930337346448646612254452369009474497523... | #Nim | Nim | import bigints
proc powmod(b, e, m: BigInt): BigInt =
assert e >= 0
var e = e
var b = b
result = initBigInt(1)
while e > 0:
if e mod 2 == 1:
result = (result * b) mod m
e = e div 2
b = (b.pow 2) mod m
var
a = initBigInt("29883481620585741369158914214988194663201633129269524237910230788... | Give a code snippet in #Nim
Find the last 40 decimal digits of
a
b
{\displaystyle a^{b}}
, where
a
=
2988348162058574136915891421498819466320163312926952423791023078876139
{\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139}
b
=
2351399303373464... | 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... | #Ursala | Ursala | #import flo
#import nat
#cast %e
total = plus:-0 div/*1. sqr* float*t iota 1001 | Give a code snippet in #Ursala
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
=
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mertens_function | Mertens function | The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number.
It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbius numbers from n == 1 through n... | #Forth | Forth | : AMOUNT 1000 ;
variable mertens AMOUNT cells allot
: M 1- cells mertens + ; \ 1-indexed array
: make-mertens
1 1 M !
2 begin dup AMOUNT <= while
1 over M !
2 begin over over >= while
over over / M @
2 pick M @ swap -
2 pick M !
1+ repeat
drop
1+ repeat
drop
;
: print... | Give a code snippet in #Forth
The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number.
It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbiu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations | Combinations | Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 4
0 3 4
1 2 3
1 2 4
1 3 4
2 3 4
... | #Delphi | Delphi | def combinations(m, range) {
return if (m <=> 0) { [[]] } else {
def combGenerator {
to iterate(f) {
for i in range {
for suffix in combinations(m.previous(), range & (int > i)) {
f(null, [i] + suffix)
}
}
}
}
}
} | Give a code snippet in #Delphi
Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm | Bitmap/Bresenham's line algorithm | Task
Using the data storage type defined on the Bitmap page for raster graphics images,
draw a line given two points with Bresenham's line algorithm.
| #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
[SetVid($112); \set 640x480 graphics in 24-bit color
Move(10, 20); \set start of line segment
Line(600, 400, $123456);\draw line segment, red=$12, green=$34, blue=$56
if ChIn(1) then []; \wait for keystroke while viewing graphic screen
SetVid... | Give a code snippet in #XPL0
Task
Using the data storage type defined on the Bitmap page for raster graphics images,
draw a line given two points with Bresenham's line algorithm.
| 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 ... | #VBScript | VBScript |
WScript.Echo DotProduct("1,3,-5","4,-2,-1")
Function DotProduct(vector1,vector2)
arrv1 = Split(vector1,",")
arrv2 = Split(vector2,",")
If UBound(arrv1) <> UBound(arrv2) Then
WScript.Echo "The vectors are not of the same length."
Exit Function
End If
DotProduct = 0
For i = 0 To UBound(arrv1)
DotProduct =... | Give a code snippet in #VBScript
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,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/EKG_sequence_convergence | EKG sequence convergence | The sequence is from the natural numbers and is defined by:
a(1) = 1;
a(2) = Start = 2;
for n > 2, a(n) shares at least one prime factor with a(n-1) and is the smallest such natural number not already used.
The sequence is called the EKG sequence (after its visual similarity to an electrocardiogram when graphed).... | #11l | 11l | F ekg(n, limit)
Set[Int] values
assert(n >= 2)
V r = [(1, 1), (2, n)]
values.add(n)
V i = 3
V prev = n
L i <= limit
V val = 2
L
I val !C values & gcd(val, prev) != 1
values.add(val)
r [+]= (i, val)
prev = val
L.break
val+... | Give a code snippet in #11l
The sequence is from the natural numbers and is defined by:
a(1) = 1;
a(2) = Start = 2;
for n > 2, a(n) shares at least one prime factor with a(n-1) and is the smallest such natural number not already used.
The sequence is called the EKG sequence (after its visual similarity to an ele... | 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 ... | #Perl | Perl | my $N = 2200;
push @sq, $_**2 for 0 .. $N;
my @not = (0) x $N;
@not[0] = 1;
for my $d (1 .. $N) {
my $last = 0;
for my $a (reverse ceiling($d/3) .. $d) {
for my $b (1 .. ceiling($a/2)) {
my $ab = $sq[$a] + $sq[$b];
last if $ab > $sq[$d];
my $x = sqrt($sq[$d] - $ab... | Give a code snippet in #Perl
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 |
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