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/Polymorphism | Polymorphism | Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| #Tcl | Tcl | package require TclOO
oo::class create Point {
variable X Y
constructor {x y} {
set X $x
set Y $y
}
method x args {
set X {*}$args
}
method y args {
set Y {*}$args
}
method print {} {
puts "Point($X,$Y)"
}
method copy {} {
set copy ... | Give a code snippet in #Tcl
Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #Slate | Slate | define: #pairs -> ({'hello' -> 1. 'world' -> 2. '!' -> 3. 'another!' -> 3} as: Dictionary).
pairs keysAndValuesDo: [| :key :value |
inform: '(k, v) = (' ; key printString ; ', ' ; value printString ; ')'
].
pairs keysDo: [| :key |
inform: '(k, v) = (' ; key printString ; ', ' ; (pairs at: key) printString ; ')'
]... | Give a code snippet in #Slate
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Com... | 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... | #XPL0 | XPL0 | code ChOut=8, CrLf=9, IntOut=11;
func Binomial(N, K);
int N, K;
int M, B, I;
[M:= K;
if K>N/2 the M:= N-K;
B:=1;
for I:= 1 to M do
B:= B*(N-M+I)/I;
return B;
];
int N, K;
[for N:= 0 to 9 do
[for K:= 0 to 9 do
[if N>=K then IntOut(0, Binomial(N,K));
ChOut(0, 9\tab\);
];
CrLf(0);... | Give a code snippet in #XPL0
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Floyd-Warshall_algorithm | Floyd-Warshall algorithm | The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already been checked for loops, parallel ... | #Groovy | Groovy | class FloydWarshall {
static void main(String[] args) {
int[][] weights = [[1, 3, -2], [2, 1, 4], [2, 3, 3], [3, 4, 2], [4, 2, -1]]
int numVertices = 4
floydWarshall(weights, numVertices)
}
static void floydWarshall(int[][] weights, int numVertices) {
double[][] dist = ne... | Give a code snippet in #Groovy
The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_names | Number names | Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than positive integers (like zero, negat... | #CoffeeScript | CoffeeScript |
spell_integer = (n) ->
tens = [null, null, "twenty", "thirty", "forty",
"fifty", "sixty", "seventy", "eighty", "ninety"]
small = ["zero", "one", "two", "three", "four", "five",
"six", "seven", "eight", "nine", "ten", "eleven",
"twelve", "thirteen", "fourteen", "fifteen",
"sixteen", "s... | Give a code snippet in #CoffeeScript
Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other th... | 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
... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program bogosort64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM... | Give a code snippet in #AArch64_Assembly
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Vala | Vala |
uint i = 0;
while (++i < uint.MAX)
stdout.printf("%u\n", i);
| Give a code snippet in #Vala
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations lim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Grayscale_image | Grayscale image | Many image processing algorithms are defined for grayscale (or else monochromatic) images.
Task
Extend the data storage type defined on this page to support grayscale images.
Define two operations, one to convert a color image to a grayscale image and one for the backward conversion.
To get luminance of a color u... | #PureBasic | PureBasic | Procedure ImageGrayout(image)
Protected w, h, x, y, r, g, b, gray, color
w = ImageWidth(image)
h = ImageHeight(image)
StartDrawing(ImageOutput(image))
For x = 0 To w - 1
For y = 0 To h - 1
color = Point(x, y)
r = Red(color)
g = Green(color)
b = Blue(color)
gray = 0... | Give a code snippet in #PureBasic
Many image processing algorithms are defined for grayscale (or else monochromatic) images.
Task
Extend the data storage type defined on this page to support grayscale images.
Define two operations, one to convert a color image to a grayscale image and one for the backward convers... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_prepend | String prepend |
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 |... | #Action.21 | Action! | PROC Append(CHAR ARRAY text,suffix)
BYTE POINTER srcPtr,dstPtr
BYTE len
len=suffix(0)
IF text(0)+len>255 THEN
len=255-text(0)
FI
IF len THEN
srcPtr=suffix+1
dstPtr=text+text(0)+1
MoveBlock(dstPtr,srcPtr,len)
text(0)==+suffix(0)
FI
RETURN
PROC Prepend(CHAR ARRAY text,prefix)
CHAR ... | Give a code snippet in #Action.21
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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.2B.2B | C++ | #include <algorithm>
#include <iostream>
#include <vector>
const int STX = 0x02;
const int ETX = 0x03;
void rotate(std::string &a) {
char t = a[a.length() - 1];
for (int i = a.length() - 1; i > 0; i--) {
a[i] = a[i - 1];
}
a[0] = t;
}
std::string bwt(const std::string &s) {
for (char c... | Give a code snippet in #C.2B.2B
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 tr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Command-line_arguments | Command-line arguments | Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| #V | V | $stack puts
./args.v a b c
=[args.v a b c] | Give a code snippet in #V
Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Natural_sorting | Natural sorting |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Scala | Scala | object NaturalSorting {
implicit object ArrayOrdering extends Ordering[Array[String]] { // 4
val INT = "([0-9]+)".r
def compare(a: Array[String], b: Array[String]) = {
val l = Math.min(a.length, b.length)
(0 until l).prefixLength(i => a(i) equals b(i)) match {
case i if i == l => Math.sign... | Give a code snippet in #Scala
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/Keyboard_input/Flush_the_keyboard_buffer | Keyboard input/Flush the keyboard buffer | Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| #PureBasic | PureBasic | While Inkey(): Wend | Give a code snippet in #PureBasic
Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Straddling_checkerboard | Straddling checkerboard | Task
Implement functions to encrypt and decrypt a message using the straddling checkerboard method. The checkerboard should take a 28 character alphabet (A-Z plus a full stop and an escape character) and two different numbers representing the blanks in the first row. The output will be a series of decimal digits.
Num... | #Tcl | Tcl | package require Tcl 8.6
oo::class create StraddlingCheckerboardCypher {
variable encmap decmap
constructor table {
# Sanity check the table
foreach ch [lindex $table 0] i {"" 0 1 2 3 4 5 6 7 8 9} {
if {$ch eq "" && $i ne "" && [lsearch -index 0 $table $i] < 1} {
error "bad checkerboard table"
}
... | Give a code snippet in #Tcl
Task
Implement functions to encrypt and decrypt a message using the straddling checkerboard method. The checkerboard should take a 28 character alphabet (A-Z plus a full stop and an escape character) and two different numbers representing the blanks in the first row. The output will be a s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multi-dimensional_array | Multi-dimensional array | For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value to update the indexed value.
... | #Perl | Perl | use feature 'say';
# Perl arrays are internally always one-dimensional, but multi-dimension arrays are supported via references.
# So a two-dimensional array is an arrays-of-arrays, (with 'rows' that are references to arrays), while a
# three-dimensional array is an array of arrays-of-arrays, and so on. There are no... | Give a code snippet in #Perl
For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiple_distinct_objects | Multiple distinct objects | Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are considered unequal; etc. The code need ... | #Scala | Scala | for (i <- (0 until n)) yield new Foo() | Give a code snippet in #Scala
Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are consider... | 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... | #Crystal | Crystal | def knuthShuffle(items : Array)
i = items.size-1
while i > 1
j = Random.rand(0..i)
items.swap(i, j)
i -= 1
end
end | Give a code snippet in #Crystal
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/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #BQN | BQN | Div ← {∨´"∞"‿"NaN"≡¨<•Fmt𝕩}◶⊢‿"Division by 0"÷
•Show 5 Div 0
•Show 5 Div 5
•Show 0 Div 0 | Give a code snippet in #BQN
Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_three_variables | Sort three variables |
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
... | #R | R |
#lang R
assignVec <- Vectorize("assign", c("x", "value"))
`%<<-%` <- function(x, value) invisible(assignVec(x, value, envir = .GlobalEnv)) # define multiple global assignments operator
| Give a code snippet in #R
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Recaman%27s_sequence | Recaman's sequence | The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the... | #BCPL | BCPL | get "libhdr"
// Generate the N'th term of the Recaman sequence
// given terms 0 to N-1.
let generate(a, n) be
a!n := n=0 -> 0, valof
$( let subterm = a!(n-1) - n
let addterm = a!(n-1) + n
if subterm <= 0 resultis addterm
for i=0 to n-1
if a!i = subterm resultis addterm
... | Give a code snippet in #BCPL
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_cuboid | Draw a cuboid | Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is acceptable for this task.
R... | #Pascal | Pascal | program Cuboid_Demo(output);
procedure DoCuboid(sWidth, sHeight, Depth: integer);
const
widthScale = 4;
heightScale = 3;
type
TPage = array of array of char;
var
Cuboid: TPage;
i, j: integer;
Width, Height: integer;
totalWidth, totalHeight: integer;
begin
Width := widthScale ... | Give a code snippet in #Pascal
Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | Print[DateList[]]
Print[AbsoluteTime[]] | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_length | Array length | Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I befo... | #ColdFusion | ColdFusion |
<cfset testArray = ["apple","orange"]>
<cfoutput>Array Length = #ArrayLen(testArray)#</cfoutput>
| Give a code snippet in #ColdFusion
Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_octal | Count in octal | Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
Related task
Integer sequ... | #VBScript | VBScript |
For i = 0 To 20
WScript.StdOut.WriteLine Oct(i)
Next
| Give a code snippet in #VBScript
Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached... | 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 ... | #Fortran | Fortran |
program demo_edit_distance
character(len=:),allocatable :: sources(:),targets(:)
integer,allocatable :: answers(:),expected(:)
sources=[character(len=20) :: "kitten", "rosettacode", "Saturday", "sleep", "qwerty", "Fortran" ]
targets=[character(len=20) :: "sitting", "raisethysword", "Sunday", "f... | Give a code snippet in #Fortran
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 c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Memory_allocation | Memory allocation | Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| #SNOBOL4 | SNOBOL4 | newstring = "This is creating and saving" " a new single string " "starting with three separate strings." | Give a code snippet in #SNOBOL4
Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const proc: main is func
local
var integer: number is 0;
begin
for number range 1 to 100 do
if number rem 15 = 0 then
writeln("FizzBuzz");
elsif number rem 5 = 0 then
writeln("Buzz");
elsif number rem 3 = 0 then
writeln("Fizz");
els... | Give a code snippet in #Seed7
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Haversine_formula | Haversine formula |
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
The haversine formula is an equation important in navigation, g... | #AWK | AWK |
# syntax: GAWK -f HAVERSINE_FORMULA.AWK
# converted from Python
BEGIN {
distance(36.12,-86.67,33.94,-118.40) # BNA to LAX
exit(0)
}
function distance(lat1,lon1,lat2,lon2, a,c,dlat,dlon) {
dlat = radians(lat2-lat1)
dlon = radians(lon2-lon1)
lat1 = radians(lat1)
lat2 = radians(lat2)
a = (si... | Give a code snippet in #AWK
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
The haversine formula is an equati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #Julia | Julia |
function aliquotclassifier{T<:Integer}(n::T)
a = T[n]
b = divisorsum(a[end])
len = 1
while len < 17 && !(b in a) && 0 < b && b < 2^47+1
push!(a, b)
b = divisorsum(a[end])
len += 1
end
if b in a
1 < len || return ("Perfect", a)
if b == a[1]
2 ... | Give a code snippet in #Julia
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Runtime_evaluation/In_an_environment | Runtime evaluation/In an environment | x
x
x
Do so in a way which:
does not involve string manipulation of the input source code
is plausibly extensible to a runtime-chosen set of bindings rather than just x
does not make x a global variable
or note that these are impossible.
See also
For more general examples and language-specific details, see... | #Java | Java | import java.io.File;
import java.lang.reflect.Method;
import java.net.URI;
import java.util.Arrays;
import javax.tools.JavaCompiler;
import javax.tools.SimpleJavaFileObject;
import javax.tools.ToolProvider;
public class Eval {
private static final String CLASS_NAME = "TempPleaseDeleteMe";
private static cla... | Give a code snippet in #Java
x
x
x
Do so in a way which:
does not involve string manipulation of the input source code
is plausibly extensible to a runtime-chosen set of bindings rather than just x
does not make x a global variable
or note that these are impossible.
See also
For more general examples and ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #Racket | Racket | #lang racket/base
(require racket/match
racket/string
math/number-theory)
(define simplify-arithmetic-expression
(letrec ((s-a-e
(match-lambda
[(list (and op '+) l ... (list '+ m ...) r ...) (s-a-e `(,op ,@l ,@m ,@r))]
[(list (and op '+) l ... (? number? n... | Give a code snippet in #Racket
In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expres... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_stability | Sort stability |
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
... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program stableSort641.s */
/* use merge sort and pointer table */
/* but use a extra table of pointer for the merge */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for ... | Give a code snippet in #AArch64_Assembly
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Equilibrium_index | Equilibrium index | An equilibrium index of a sequence is an index into the sequence such that the sum of elements at lower indices is equal to the sum of elements at higher indices.
For example, in a sequence
A
{\displaystyle A}
:
A
0
=
−
7
{\displaystyle A_{0}=-7}
A
1
=
1
{\displaystyle A_{1}=1}
... | #PowerShell | PowerShell |
function Get-EquilibriumIndex ( $Sequence )
{
$Indexes = 0..($Sequence.Count - 1)
$EqulibriumIndex = @()
ForEach ( $TestIndex in $Indexes )
{
$Left = 0
$Right = 0
ForEach ( $Index in $Indexes )
{
If ( $Index -lt $TestIndex ) { $Left += $Se... | Give a code snippet in #PowerShell
An equilibrium index of a sequence is an index into the sequence such that the sum of elements at lower indices is equal to the sum of elements at higher indices.
For example, in a sequence
A
{\displaystyle A}
:
A
0
=
−
7
{\displaystyle A_{0}=-7}
A... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #Stata | Stata | qui sum x
di r(max) | Give a code snippet in #Stata
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/French_Republican_calendar | French Republican calendar | Write a program to convert dates between the Gregorian calendar and the French Republican calendar.
The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of... | #Sidef | Sidef | require('DateTime')
var month_names = %w(
Vendémiaire Brumaire Frimaire Nivôse Pluviôse Ventôse
Germinal Floréal Prairial Messidor Thermidor Fructidor
)
var intercalary = [
'Fête de la vertu',
'Fête du génie',
'Fête du travail',
... | Give a code snippet in #Sidef
Write a program to convert dates between the Gregorian calendar and the French Republican calendar.
The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messido... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hamming_numbers | Hamming numbers | Hamming numbers are numbers of the form
H = 2i × 3j × 5k
where
i, j, k ≥ 0
Hamming numbers are also known as ugly numbers and also 5-smooth numbers (numbers whose prime divisors are less or equal to 5).
Task
Generate the sequence of Hamming numbers, in increasing order. In ... | #Scheme | Scheme | (define-syntax lons
(syntax-rules ()
((_ lar ldr) (delay (cons lar (delay ldr))))))
(define (lar lons)
(car (force lons)))
(define (ldr lons)
(force (cdr (force lons))))
(define (lap proc . llists)
(lons (apply proc (map lar llists)) (apply lap proc (map ldr llists))))
(define (take n llist)
(if (... | Give a code snippet in #Scheme
Hamming numbers are numbers of the form
H = 2i × 3j × 5k
where
i, j, k ≥ 0
Hamming numbers are also known as ugly numbers and also 5-smooth numbers (numbers whose prime divisors are less or equal to 5).
Task
Generate the sequence of Hamming num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Taxicab_numbers | Taxicab numbers |
A taxicab number (the definition that is being used here) is a positive integer that can be expressed as the sum of two positive cubes in more than one way.
The first taxicab number is 1729, which is:
13 + 123 and also
93 + 103.
Taxicab numbers are also known as:
taxi numbers
tax... | #Python | Python | from collections import defaultdict
from itertools import product
from pprint import pprint as pp
cube2n = {x**3:x for x in range(1, 1201)}
sum2cubes = defaultdict(set)
for c1, c2 in product(cube2n, cube2n):
if c1 >= c2: sum2cubes[c1 + c2].add((cube2n[c1], cube2n[c2]))
taxied = sorted((k, v) for k,v in sum2cubes.i... | Give a code snippet in #Python
A taxicab number (the definition that is being used here) is a positive integer that can be expressed as the sum of two positive cubes in more than one way.
The first taxicab number is 1729, which is:
13 + 123 and also
93 + 103.
Taxicab numbers are also k... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #UnixPipes | UnixPipes | yes SPAM | Give a code snippet in #UnixPipes
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fork | Fork | Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| #PHP | PHP | <?php
$pid = pcntl_fork();
if ($pid == 0)
echo "This is the new process\n";
else if ($pid > 0)
echo "This is the original process\n";
else
echo "ERROR: Something went wrong\n";
?> | Give a code snippet in #PHP
Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file_on_magnetic_tape | Create a file on magnetic tape | The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| #Haskell | Haskell | module Main (main) where
main :: IO ()
main = writeFile "/dev/tape" "Hello from Rosetta Code!" | Give a code snippet in #Haskell
The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Environment_variables | Environment variables | Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| #CoffeeScript | CoffeeScript | for var_name in ['PATH', 'HOME', 'LANG', 'USER']
console.log var_name, process.env[var_name] | Give a code snippet in #CoffeeScript
Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Undersc... | #C | C | #include <stdbool.h>
#include <stdio.h>
#include <glib.h>
typedef struct word_count_tag {
const char* word;
size_t count;
} word_count;
int compare_word_count(const void* p1, const void* p2) {
const word_count* w1 = p1;
const word_count* w2 = p2;
if (w1->count > w2->count)
return -1;
... | Give a code snippet in #C
Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Convert | Non-decimal radices/Convert | Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in binary, but that's typically invisibl... | #FunL | FunL | $stdout = int( '1a', 16 ) | Give a code snippet in #FunL
Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in binary,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Arithmetic_mean | Averages/Arithmetic mean | Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin... | #SQL | SQL |
CREATE TABLE "numbers" ("datapoint" INTEGER);
INSERT INTO "numbers" SELECT rownum FROM tab;
SELECT SUM("datapoint")/COUNT(*) FROM "numbers";
| Give a code snippet in #SQL
Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an establ... | 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... | #Perl | Perl | use Benchmark;
timethese COUNT,{ 'Job1' => &job1, 'Job2' => &job2 };
sub job1
{
...job1 code...
}
sub job2
{
...job2 code...
} | Give a code snippet in #Perl
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 thes... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #ATS | ATS |
fun fib_rec(n: int): int =
if n >= 2 then fib_rec(n-1) + fib_rec(n-2) else n
| Give a code snippet in #ATS
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are g... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Prolog | Prolog | :- use_module(library(clpfd)).
roman :-
LA = [ _ , 2010, _, 1449, _],
LR = ['MDCCLXXXIX', _ , 'CX', _, 'MDCLXVI'],
maplist(roman, LA, LR),
maplist(my_print,LA, LR).
roman(A, R) :-
A #> 0,
roman(A, [u, t, h, th], LR, []),
label([A]),
parse_Roman(CR, LR, []),
atom_chars(R, CR).... | Give a code snippet in #Prolog
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a va... | 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... | #Commodore_BASIC | Commodore BASIC | 1 rem password generator
2 rem rosetta code
10 g$(1)="abcdefghijklmnopqrstuvwxyz"
15 g$(2)="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
20 g$(3)="0123456789"
25 g$(4)="<>!@#$%^&*()[];:'.?/"
30 print chr$(147);chr$(14)
35 print "Password Generator":print
40 print "Press H for help, or any":print "other key to begin.":print
45 get k$:if... | Give a code snippet in #Commodore_BASIC
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/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #SSEM | SSEM | 00101000000000100000000000000000 0. -20 to c
11001000000000010000000000000000 1. Sub. 19
10101000000001100000000000000000 2. c to 21
10101000000000100000000000000000 3. -21 to c
00000000000000110000000000000000 4. Test
10001000000000000000000000000000 5. 17 to CI
10101000000001100000000000000000 6. c to 2... | Give a code snippet in #SSEM
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-continuous_subsequences | Non-continuous subsequences | Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.)
A subsequence contains some subset of the elements of this sequence, in the same order.
A continuous subsequence is one in which no elements are missing between the first and last elements of the subseque... | #Scheme | Scheme | (define (ncsubseq lst)
(let recurse ((s 0)
(lst lst))
(if (null? lst)
(if (>= s 3)
'(())
'())
(let ((x (car lst))
(xs (cdr lst)))
(if (even? s)
(append
(map (lambda (ys) (cons x ys))
(r... | Give a code snippet in #Scheme
Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.)
A subsequence contains some subset of the elements of this sequence, in the same order.
A continuous subsequence is one in which no elements are missing between the first a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #REXX | REXX | /*REXX program outputs its own 1─line source.*/ say sourceline(1) | Give a code snippet in #REXX
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lychrel_numbers | Lychrel numbers | Take an integer n, greater than zero.
Form the next n of its series by reversing the digits of the current n and adding the result to the current n.
Stop when n becomes palindromic - i.e. the digits of n in reverse order == n.
The above recurrence relation when applied to most starting numbers n = 1, 2, ... ... | #Fortran | Fortran |
SUBROUTINE CROAK(GASP) !A dying message.
CHARACTER*(*) GASP !The message.
WRITE (6,*) "Oh dear! ",GASP !The gasp.
STOP "Alas." !The death.
END !Goodbye, cruel world.
MODULE LYCHREL SEARCH !Assistants for the pursuit of Lychrel numbers.
INTEGER LOTSADIGITS,BASE !Par... | Give a code snippet in #Fortran
Take an integer n, greater than zero.
Form the next n of its series by reversing the digits of the current n and adding the result to the current n.
Stop when n becomes palindromic - i.e. the digits of n in reverse order == n.
The above recurrence relation when applied to mos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Complex | Arithmetic/Complex | A complex number is a number which can be written as:
a
+
b
×
i
{\displaystyle a+b\times i}
(sometimes shown as:
b
+
a
×
i
{\displaystyle b+a\times i}
where
a
{\displaystyle a}
and
b
{\displaystyle b}
are real numbers, and
i
{\displaystyle i}
is √ -1
Typica... | #AWK | AWK | # simulate a struct using associative arrays
function complex(arr, re, im) {
arr["re"] = re
arr["im"] = im
}
function re(cmplx) {
return cmplx["re"]
}
function im(cmplx) {
return cmplx["im"]
}
function printComplex(cmplx) {
print re(cmplx), im(cmplx)
}
function abs2(cmplx) {
return re(cm... | Give a code snippet in #AWK
A complex number is a number which can be written as:
a
+
b
×
i
{\displaystyle a+b\times i}
(sometimes shown as:
b
+
a
×
i
{\displaystyle b+a\times i}
where
a
{\displaystyle a}
and
b
{\displaystyle b}
are real numbers, and
i
{\displaystyl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Damm_algorithm | Damm algorithm | The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors.
The algorithm is named after H. Michael Damm.
Task
Verify the checksum, stored as last digit of an input.
| #PHP | PHP | <?php
function lookup($r,$c) {
$table = array(
array(0, 3, 1, 7, 5, 9, 8, 6, 4, 2),
array(7, 0, 9, 2, 1, 5, 4, 8, 6, 3),
array(4, 2, 0, 6, 8, 7, 1, 3, 5, 9),
array(1, 7, 5, 0, 9, 8, 3, 4, 2, 6),
array(6, 1, 2, 3, 0, 4, 5, 9, 7, 8),
array(3, 6, 7, 4, 2, 0, 9, 5, 8, 1),... | Give a code snippet in #PHP
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors.
The algorithm is named after H. Michael Damm.
Task
Verify the checksum, stored as last digit of an input.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Babbage_problem | Babbage problem |
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Computers, second edition, 1970, p.... | #Quackery | Quackery | ( . . . . . . . . . . . . . . . . . . )
( The computer will ignore anything between parentheses, providing there is
a space or carriage return on either side of each parenthesis. )
( . . . . . . . . . . . . . . . . . . )
( A ... | Give a code snippet in #Quackery
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lah_numbers | Lah numbers | Lah numbers, sometimes referred to as Stirling numbers of the third kind, are coefficients of polynomial expansions expressing rising factorials in terms of falling factorials.
Unsigned Lah numbers count the number of ways a set of n elements can be partitioned into k non-empty linearly ordered subsets.
Lah numbers a... | #Kotlin | Kotlin | import java.math.BigInteger
fun factorial(n: BigInteger): BigInteger {
if (n == BigInteger.ZERO) return BigInteger.ONE
if (n == BigInteger.ONE) return BigInteger.ONE
var prod = BigInteger.ONE
var num = n
while (num > BigInteger.ONE) {
prod *= num
num--
}
return prod
}
fun... | Give a code snippet in #Kotlin
Lah numbers, sometimes referred to as Stirling numbers of the third kind, are coefficients of polynomial expansions expressing rising factorials in terms of falling factorials.
Unsigned Lah numbers count the number of ways a set of n elements can be partitioned into k non-empty linearly... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brownian_tree | Brownian tree | Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "seed" is placed somewhere wi... | #Scheme | Scheme | ; Save bitmap to external file
(define (save-pbm bitmap filename)
(define f (open-output-file filename))
(simple-format f "P1\n~A ~A\n"
(list-ref (array-dimensions bitmap) 0)
(list-ref (array-dimensions bitmap) 1))
(do ((c 0 (+ c 1))) ((eqv? c (list-ref (array-dimensions bitmap) 1)))
(do ((r 0 (+ r 1))) ((eqv? ... | Give a code snippet in #Scheme
Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Accumulator_factory | Accumulator factory | A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed in so far to that accumulat... | #Maple | Maple | AccumulatorFactory := proc( initial := 0 )
local total := initial;
proc( val := 1 ) total := total + val end
end proc: | Give a code snippet in #Maple
A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values pas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Iterated_digits_squaring | Iterated digits squaring | If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89:
15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89
7 -> 49 -> 97 -> 130 -> 10 -> 1
An example in Python:
>>> step = lambda x: sum(int(d) ** 2 for d in str(x))
>>> iterate = lambda x: x if x in [1, 89] else i... | #Go | Go | package main
import (
"fmt"
)
func main() {
var d, n, o, u, u89 int64
for n = 1; n < 100000000; n++ {
o = n
for {
u = 0
for {
d = o%10
o = (o - d) / 10
u += d*d
if o == 0 {
break
}
}
if u == 89 || u == 1 {
if u == 89 { u89++ }
break
}
o = u
}
}
fmt.Pr... | Give a code snippet in #Go
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89:
15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89
7 -> 49 -> 97 -> 130 -> 10 -> 1
An example in Python:
>>> step = lambda x: sum(int(d) ** 2 for d in str(x))
>>> iterate = lambda... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #hexiscript | hexiscript | println "File \"input.txt\"? " + (exists "input.txt")
println "Dir \"docs\"? " + (exists "docs/")
println "File \"/input.txt\"? " + (exists "/input.txt")
println "Dir \"/docs\"? " + (exists "/docs/") | Give a code snippet in #hexiscript
Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it work... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nonogram_solver | Nonogram solver | A nonogram is a puzzle that provides
numeric clues used to fill in a grid of cells,
establishing for each cell whether it is filled or not.
The puzzle solution is typically a picture of some kind.
Each row and column of a rectangular grid is annotated with the lengths
of its distinct runs of occupied cells.
Using only... | #C.23 | C# | using System;
using System.Collections.Generic;
using static System.Linq.Enumerable;
public static class NonogramSolver
{
public static void Main2() {
foreach (var (x, y) in new [] {
("C BA CB BB F AE F A B", "AB CA AE GA E C D C"),
("F CAC ACAC CN AAA AABB EBB EAA ECCC HCCC",
... | Give a code snippet in #C.23
A nonogram is a puzzle that provides
numeric clues used to fill in a grid of cells,
establishing for each cell whether it is filled or not.
The puzzle solution is typically a picture of some kind.
Each row and column of a rectangular grid is annotated with the lengths
of its distinct runs... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #Quackery | Quackery | /O> 0 0 **
...
Stack: 1
| Give a code snippet in #Quackery
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_operations | Bitwise operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #F.23 | F# | let bitwise a b =
printfn "a and b: %d" (a &&& b)
printfn "a or b: %d" (a ||| b)
printfn "a xor b: %d" (a ^^^ b)
printfn "not a: %d" (~~~a)
printfn "a shl b: %d" (a <<< b)
printfn "a shr b: %d" (a >>> b) // arithmetic shift
printfn "a shr b: %d" ((uint32 a) >>> b) // logical shif... | Give a code snippet in #F.23
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #xEec | xEec | i# i# ma h#10 r o# p o$ p | Give a code snippet in #xEec
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #TXR | TXR | $ txr -p '(n-perm-k 10 10)'
3628800 | Give a code snippet in #TXR
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_inverse | Modular inverse | From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{\displaystyle \exists k\in \math... | #uBasic.2F4tH | uBasic/4tH | Print FUNC(_MulInv(42, 2017))
End
_MulInv Param(2)
Local(5)
c@ = b@
f@ = 0
g@ = 1
If b@ = 1 Then Return
Do While a@ > 1
e@ = a@ / b@
d@ = b@
b@ = a@ % b@
a@ = d@
d@ = f@
f@ = g@ - e@ * f@
g@ = d@
Loop
If g@ < 0 Then g@ = g@ + c@
Return (g@) | Give a code snippet in #uBasic.2F4tH
From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #Groovy | Groovy | def keys = ['a','b','c']
def vals = ['aaa', 'bbb', 'ccc']
def hash = [:]
keys.eachWithIndex { key, i ->
hash[key] = vals[i]
} | Give a code snippet in #Groovy
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_substring | Longest common substring | Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecutive characters within a string.... | #J | J | lcstr=:4 :0
C=. ({.~ 1+$) x=/y
M=. >./ (* * * >. * + (_1&|.)@:|:^:2)^:_ C
N=. >./ M
y {~ (M i. N)-i.-N
) | Give a code snippet in #J
Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecutive ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_input_device_is_a_terminal | Check input device is a terminal | Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| #C | C | #include <unistd.h> //for isatty()
#include <stdio.h> //for fileno()
int main(void)
{
puts(isatty(fileno(stdin))
? "stdin is tty"
: "stdin is not tty");
return 0;
} | Give a code snippet in #C
Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Solve_the_no_connection_puzzle | Solve the no connection puzzle | You are given a box with eight holes labelled A-to-H, connected by fifteen straight lines in the pattern as shown below:
A B
/│\ /│\
/ │ X │ \
/ │/ \│ \
C───D───E───F
\ │\ /│ /
\ │ X │ /
\│/ \│/
G H
You ar... | #Kotlin | Kotlin | // version 1.2.0
import kotlin.math.abs
// Holes A=0, B=1, …, H=7
// With connections:
const val conn = """
A B
/|\ /|\
/ | X | \
/ |/ \| \
C - D - E - F
\ |\ /| /
\ | X | /
\|/ \|/
G H
"""
val connections = listOf(
0 to 2, 0 to 3, 0 to 4, // A to C, D,... | Give a code snippet in #Kotlin
You are given a box with eight holes labelled A-to-H, connected by fifteen straight lines in the pattern as shown below:
A B
/│\ /│\
/ │ X │ \
/ │/ \│ \
C───D───E───F
\ │\ /│ /
\ │ X │ /
\│... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Equilibrium_index | Equilibrium index | An equilibrium index of a sequence is an index into the sequence such that the sum of elements at lower indices is equal to the sum of elements at higher indices.
For example, in a sequence
A
{\displaystyle A}
:
A
0
=
−
7
{\displaystyle A_{0}=-7}
A
1
=
1
{\displaystyle A_{1}=1}
... | #Raku | Raku | sub equilibrium_index(@list) {
my ($left,$right) = 0, [+] @list;
gather for @list.kv -> $i, $x {
$right -= $x;
take $i if $left == $right;
$left += $x;
}
}
my @list = -7, 1, 5, 2, -4, 3, 0;
.say for equilibrium_index(@list).grep(/\d/); | Give a code snippet in #Raku
An equilibrium index of a sequence is an index into the sequence such that the sum of elements at lower indices is equal to the sum of elements at higher indices.
For example, in a sequence
A
{\displaystyle A}
:
A
0
=
−
7
{\displaystyle A_{0}=-7}
A
1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm | Trabb Pardo–Knuth algorithm | The TPK algorithm is an early example of a programming chrestomathy.
It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages.
The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of... | #D | D | import std.stdio, std.math, std.conv, std.algorithm, std.array;
double f(in double x) pure nothrow {
return x.abs.sqrt + 5 * x ^^ 3;
}
void main() {
double[] data;
while (true) {
"Please enter eleven numbers on a line: ".write;
data = readln.split.map!(to!double).array;
if (dat... | Give a code snippet in #D
The TPK algorithm is an early example of a programming chrestomathy.
It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages.
The report traces the early history of work in developing computer languages in the 1940s and 1950s, giv... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Input_loop | Input loop | Input loop is part of Short Circuit's Console Program Basics selection.
Task
Read from a text stream either word-by-word or line-by-line until the stream runs out of data.
The stream will have an unknown amount of data on it.
| #Mercury | Mercury |
:- module input_loop.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
main(!IO) :-
io.stdin_stream(Stdin, !IO),
io.stdout_stream(Stdout, !IO),
read_and_print_lines(Stdin, Stdout, !IO).
:- pred read_and_print_lines(io.text_input_stream::in,
io.text_out... | Give a code snippet in #Mercury
Input loop is part of Short Circuit's Console Program Basics selection.
Task
Read from a text stream either word-by-word or line-by-line until the stream runs out of data.
The stream will have an unknown amount of data on it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #Scala | Scala | val q = "\"" * 3
val c = """val q = "\"" * 3
val c = %s%s%s
println(c format (q, c, q))
"""
println(c format (q, c, q)) | Give a code snippet in #Scala
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Element_insertion | Doubly-linked list/Element insertion | Doubly-Linked List (element)
This is much like inserting into a Singly-Linked List, but with added assignments so that the backwards-pointing links remain correct.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element inse... | #C.23 | C# | static void InsertAfter(Link prev, int i)
{
if (prev.next != null)
{
prev.next.prev = new Link() { item = i, prev = prev, next = prev.next };
prev.next = prev.next.prev;
}
else
prev.next = new Link() { item = i, prev = prev };
} | Give a code snippet in #C.23
Doubly-Linked List (element)
This is much like inserting into a Singly-Linked List, but with added assignments so that the backwards-pointing links remain correct.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, El... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Break | Loops/Break | Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If the number 10 is never gener... | #C.23 | C# | class Program
{
static void Main(string[] args)
{
Random random = new Random();
while (true)
{
int a = random.Next(20);
Console.WriteLine(a);
if (a == 10)
break;
int b = random.Next(20)
Console.WriteLine(b);
... | Give a code snippet in #C.23
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
I... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #Sparkling | Sparkling | spn:3> repeat("na", 8) .. " Batman!"
= nananananananana Batman! | Give a code snippet in #Sparkling
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*",... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm | Bitmap/Midpoint circle algorithm | Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| #Nim | Nim | import bitmap
proc setPixel(img: Image; x, y: int; color: Color) {.inline.} =
# Set a pixel at a given color.
# Ignore if the point is outside of the image.
if x in 0..<img.w and y in 0..<img.h:
img[x, y] = color
proc drawCircle(img: Image; center: Point; radius: Natural; color: Color) =
## Draw a cir... | Give a code snippet in #Nim
Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #R | R | library(gWidgets)
library(gWidgetstcltk)
win <- gwindow()
lab <- glabel("There have been no clicks yet", container=win)
btn <- gbutton("click me", container=win, handle=function(h, ...)
{
val <- as.numeric(svalue(lab))
svalue(lab) <- ifelse(is.na(val) ,"1", as.character(val + 1))
}
) | Give a code snippet in #R
Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Brownian_tree | Brownian tree | Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "seed" is placed somewhere wi... | #PureBasic | PureBasic | #Window1 = 0
#Image1 = 0
#ImgGadget = 0
#NUM_PARTICLES = 3000
#width = 200
#height = 200
#xmax = #width -3
#ymax = #height -3
Define.i Event ,i ,x,y
If OpenWindow(#Window1, 0, 0, #width, #height, "Brownian Tree PureBasic Example", #PB_Window_SystemMenu )
If CreateImage(#Ima... | Give a code snippet in #PureBasic
Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #Factor | Factor | : spam ( -- ) "SPAM" print spam ; | Give a code snippet in #Factor
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #zkl | zkl | fcn move(n, from,to,via){
if (n>0){
move(n-1, from,via,to);
println("Move disk from pole %d to pole %d".fmt(from, to));
move(n-1, via,to,from);
}
}
move(3, 1,2,3); | Give a code snippet in #zkl
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Closures/Value_capture | Closures/Value capture | Task
Create a list of ten functions, in the simplest manner possible (anonymous functions are encouraged), such that the function at index i (you may choose to start i from either 0 or 1), when run, should return the square of the index, that is, i 2.
Display the result of runnin... | #Standard_ML | Standard ML |
List.map (fn x => x () ) ( List.tabulate (10,(fn i => (fn ()=> i*i)) ) ) ;
| Give a code snippet in #Standard_ML
Task
Create a list of ten functions, in the simplest manner possible (anonymous functions are encouraged), such that the function at index i (you may choose to start i from either 0 or 1), when run, should return the square of the index, that is, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_name | Program name | The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A... | #Phixmonti | Phixmonti | argument 1 get ? | Give a code snippet in #Phixmonti
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the scr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #SNOBOL4 | SNOBOL4 | define('sieve(n)i,j,k,p,str,res') :(sieve_end)
sieve i = lt(i,n - 1) i + 1 :f(sv1)
str = str (i + 1) ' ' :(sieve)
sv1 str break(' ') . j span(' ') = :f(return)
sieve = sieve j ' '
sieve = gt(j ^ 2,n) sieve str :s(return) ;* Opt1
res = ''
str (arb ' ') @p ((j ^ 2) ' ... | Give a code snippet in #SNOBOL4
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N%27th | N'th | Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show here the output for at least t... | #Ada | Ada | with Ada.Text_IO;
procedure Nth is
function Suffix(N: Natural) return String is
begin
if N mod 10 = 1 and then N mod 100 /= 11 then return "st";
elsif N mod 10 = 2 and then N mod 100 /= 12 then return "nd";
elsif N mod 10 = 3 and then N mod 100 /= 13 then return "rd";
else return "t... | Give a code snippet in #Ada
Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show h... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Plain_English | Plain English | \All required helper routines already exist in Plain English:
\
\To cut a number in half:
\Divide the number by 2.
\
\To double a number:
\Add the number to the number.
\
\To decide if a number is odd:
\Privatize the number.
\Bitwise and the number with 1.
\If the number is 0, say no.
\Say yes.
To run:
Start up.
Put ... | Give a code snippet in #Plain_English
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainder... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/Continuous | Knapsack problem/Continuous |
A thief burgles a butcher's shop, where he can select from some items.
The thief knows the weights and prices of each items. Because he has a knapsack with 15 kg maximal capacity, he wants to select the items such that he would have his profit maximized. He may cut the items; the item has a reduced price after... | #Forth | Forth | include lib/selcsort.4th \ use a tiny sorting algorithm
150 value left \ capacity in 1/10th kilo
create items \ list of items
," beef" 38 , 3600 , \ description, weight, price (cents)
," pork" 54 , 4300 , \ weight in... | Give a code snippet in #Forth
A thief burgles a butcher's shop, where he can select from some items.
The thief knows the weights and prices of each items. Because he has a knapsack with 15 kg maximal capacity, he wants to select the items such that he would have his profit maximized. He may cut the items; the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring/Top_and_tail | Substring/Top and tail | The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
If the program uses UTF-8 or UTF... | #Scheme | Scheme | (define (string-top s)
(if (string=? s "") s (substring s 0 (- (string-length s) 1))))
(define (string-tail s)
(if (string=? s "") s (substring s 1 (string-length s))))
(define (string-top-tail s)
(string-tail (string-top s))) | Give a code snippet in #Scheme
The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zeckendorf_arithmetic | Zeckendorf arithmetic | This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation.
The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions.
Addition
Like bin... | #Racket | Racket | #lang racket (require math)
(define sqrt5 (sqrt 5))
(define phi (* 0.5 (+ 1 sqrt5)))
;; What is the nth fibonnaci number, shifted by 2 so that
;; F(0) = 1, F(1) = 2, ...?
;;
(define (F n)
(fibonacci (+ n 2)))
;; What is the largest n such that F(n) <= m?
;;
(define (F* m)
(let ([n (- (inexact->exact (round (/... | Give a code snippet in #Racket
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation.
The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Action.21 | Action! | SET EndProg=* | Give a code snippet in #Action.21
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #Sidef | Sidef | var arr = [1,2,3,4,5];
# Creates a new array
var new = arr.grep {|i| i %% 2};
say new.dump; # => [2, 4]
# Destructive (at variable level)
arr.grep! {|i| i %% 2};
say arr.dump; # => [2, 4] | Give a code snippet in #Sidef
Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 ... | #TI-83_BASIC | TI-83 BASIC | 5->N
DelVar [F]
{N,N}→dim([F])
1→A: N→B
1→C: N→D
0→E: E→G
1→I: 1→J
For(K,1,N*N)
K-1→[F](I,J)
If E=0: Then
If J<D: Then
J+1→J
Else: 1→G
I+1→I: A+1→A
End
End
If E=1: Then
If I<B: Then
I+1→I
Else: 2→G
J-1→J: D-1→D
End
End
If E=2: Then
If J>C: Then
J-1→J
Else: 3→G
I-1→I: B-1→B
End
End
If E=3: Then
If I>A: Then
I-1→I
E... | Give a code snippet in #TI-83_BASIC
Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractal_tree | Fractal tree | Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| #Action.21 | Action! | DEFINE MAXSIZE="12"
INT ARRAY SinTab=[
0 4 9 13 18 22 27 31 36 40 44 49 53 58 62 66 71 75 79 83
88 92 96 100 104 108 112 116 120 124 128 132 136 139 143
147 150 154 158 161 165 168 171 175 178 181 184 187 190
193 196 199 202 204 207 210 212 215 217 219 222 224 226
228 230 232 234 236 237 239 241 242 243 245... | Give a code snippet in #Action.21
Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #MAXScript | MAXScript | -- Returns filesize in bytes or 0 if the file is missing
getFileSize "index.txt"
getFileSize "\index.txt" | Give a code snippet in #MAXScript
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix-exponentiation_operator | Matrix-exponentiation operator | Most programming languages have a built-in implementation of exponentiation for integers and reals only.
Task
Demonstrate how to implement matrix exponentiation as an operator.
| #Fortran | Fortran | module matmod
implicit none
! Overloading the ** operator does not work because the compiler cannot
! differentiate between matrix exponentiation and the elementwise raising
! of an array to a power therefore we define a new operator
interface operator (.matpow.)
module procedure matrix_exp
end interface
... | Give a code snippet in #Fortran
Most programming languages have a built-in implementation of exponentiation for integers and reals only.
Task
Demonstrate how to implement matrix exponentiation as an operator.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #Oz | Oz | fun {IsNumeric S}
{String.isInt S} orelse {String.isFloat S}
end | Give a code snippet in #Oz
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Arra... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_names | Number names | Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than positive integers (like zero, negat... | #Kotlin | Kotlin | // version 1.1.2
val oneNames = listOf(
"", "one", "two", "three", "four",
"five", "six", "seven", "eight", "nine",
"ten", "eleven", "twelve", "thirteen", "fourteen",
"fifteen", "sixteen", "seventeen", "eighteen", "nineteen")
val tenNames = listOf(
"", "", "twenty", "thirty", "... | Give a code snippet in #Kotlin
Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than pos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_numbers | Perfect numbers | Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself).
Note: The faster Luca... | #Dyalect | Dyalect | func isPerfect(num) {
var sum = 0
for i in 1..<num {
if !i {
break
}
if num % i == 0 {
sum += i
}
}
return sum == num
}
let max = 33550337
print("Perfect numbers from 0 to \(max):")
for x in 0..max {
if isPerfect(x) {
print("\(x) is... | Give a code snippet in #Dyalect
Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itse... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_dates | Palindrome dates | Today (2020-02-02, at the time of this writing) happens to be a palindrome, without the hyphens, not only for those countries which express their dates in the yyyy-mm-dd format but, unusually, also for countries which use the dd-mm-yyyy format.
Task
Write a program which calculates and shows th... | #Rust | Rust | // [dependencies]
// chrono = "0.4"
fn is_palindrome(s: &str) -> bool {
s.chars().rev().eq(s.chars())
}
fn main() {
let mut date = chrono::Utc::today();
let mut count = 0;
while count < 15 {
if is_palindrome(&date.format("%Y%m%d").to_string()) {
println!("{}", date.format("%F"));... | Give a code snippet in #Rust
Today (2020-02-02, at the time of this writing) happens to be a palindrome, without the hyphens, not only for those countries which express their dates in the yyyy-mm-dd format but, unusually, also for countries which use the dd-mm-yyyy format.
Task
Write a program... | christopher/rosetta-code |
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