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
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http://rosettacode.org/wiki/Sorting_Algorithms/Circle_Sort | Sorting Algorithms/Circle 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
... | #Fortran | Fortran |
!
module circlesort
! I have commented the code that was here and also 'tightened up' various pieces such as how swap detection was done as well
! as fixing an error where the code would exceed array bounds for odd number sized arrays.
! Also, giving some some attribution to the author. - Pete
! This code is a Fortra... | Give a code snippet in #Fortran
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_to_Windows_event_log | Write to Windows event log | Task
Write script status to the Windows Event Log
| #C.23 | C# | using System.Diagnostics;
namespace RC
{
internal class Program
{
public static void Main()
{
string sSource = "Sample App";
string sLog = "Application";
string sEvent = "Hello from RC!";
if (!EventLog.SourceExists(sSource))
EventLog.CreateEventSource(sSource, sLog... | Give a code snippet in #C.23
Task
Write script status to the Windows Event Log
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_frequency | Function frequency | Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred).
This is a static analysis: The question is not how often each function is
actually executed at runtime, but how often it is used by... | #Phix | Phix | else -- rType=FUNC|TYPE
log_function_call(rtnNo)
| Give a code snippet in #Phix
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred).
This is a static analysis: The question is not how often each function is
actually executed at runtim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Left_factorials | Left factorials | Left factorials, !n, may refer to either subfactorials or to factorial sums;
the same notation can be confusingly seen being used for the two different definitions.
Sometimes, subfactorials (also known as derangements) may use any of the notations:
!n`
!n
n¡
(It may not be vis... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "bigint.s7i";
const func bigInteger: leftFact (in integer: n) is func
result
var bigInteger: leftFact is 0_;
local
var bigInteger: factorial is 1_;
var integer: i is 0;
begin
for i range 1 to n do
leftFact +:= factorial;
factorial *:= bigInteger co... | Give a code snippet in #Seed7
Left factorials, !n, may refer to either subfactorials or to factorial sums;
the same notation can be confusingly seen being used for the two different definitions.
Sometimes, subfactorials (also known as derangements) may use any of the notations:
!n`
!n ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Objeck | Objeck | function : Multiply(a : Float, b : Float) ~, Float {
return a * b;
} | Give a code snippet in #Objeck
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract... | 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... | #BASIC | BASIC | 100 FOR I = 1 TO 20
110 GOSUB 200"FACTORIAL
120 PRINT I" = "FA$
130 NEXT I
140 END
200 FA$ = "1"
210 LET NUM = I
220 LET O = 5 - (I = 1) * 4
230 FOR F = 2 TO I
240 LET M = INT (NUM / F) * F
250 IF NUM - M GOTO 300
260 LET NUM = NUM / F
270 LET F$ = STR $(F)
... | Give a code snippet in #BASIC
Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it would... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Liberty_BASIC | Liberty BASIC | fileName$ ="F:\sample.txt"
requiredLine =7
open fileName$ for input as #i
f$ =input$( #i, lof( #i))
close #i
line7$ =word$( f$, 7, chr$( 13))
if line7$ =chr$( 13) +chr$( 10) or line7$ ="" then notice "Empty line! ( or file has fewer lines)."
print line7$ | Give a code snippet in #Liberty_BASIC
Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and st... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Menu | Menu | Task
Given a prompt and a list containing a number of strings of which one is to be selected, create a function that:
prints a textual menu formatted as an index value followed by its corresponding string for each item in the list;
prompts the user to enter a number;
returns the string corresponding to the selecte... | #True_BASIC | True BASIC | DIM menu$(4)
MAT READ menu$
DATA "fee fie", "huff and puff", "mirror mirror", "tick tock"
FUNCTION sel$(choices$())
IF UBOUND(choices$) - LBOUND(choices$) = 0 THEN LET sel$ = ""
LET ret$ = ""
DO
FOR i = LBOUND(choices$) TO UBOUND(choices$)
PRINT i; ": "; choices$(i)
NEXT i
... | Give a code snippet in #True_BASIC
Task
Given a prompt and a list containing a number of strings of which one is to be selected, create a function that:
prints a textual menu formatted as an index value followed by its corresponding string for each item in the list;
prompts the user to enter a number;
returns the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #Jsish | Jsish | /* Identity matrix, in Jsish */
function identityMatrix(n) {
var mat = new Array(n).fill(0);
for (var r in mat) {
mat[r] = new Array(n).fill(0);
mat[r][r] = 1;
}
return mat;
}
provide('identityMatrix', 1);
if (Interp.conf('unitTest')) {
; identityMatrix(0);
; identityMatrix(1);... | Give a code snippet in #Jsish
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/Shunting-yard_algorithm | Parsing/Shunting-yard algorithm | Task
Given the operator characteristics and input from the Shunting-yard algorithm page and tables, use the algorithm to show the changes in the operator stack and RPN output
as each individual token is processed.
Assume an input of a correct, space separated, string of tokens representing an infix expression
Gener... | #Ruby | Ruby | rpn = RPNExpression.from_infix("3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3") | Give a code snippet in #Ruby
Task
Given the operator characteristics and input from the Shunting-yard algorithm page and tables, use the algorithm to show the changes in the operator stack and RPN output
as each individual token is processed.
Assume an input of a correct, space separated, string of tokens represent... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Traversal | Doubly-linked list/Traversal | Traverse from the beginning of a doubly-linked list to the end, and from the end to the beginning.
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: Def... | #Scala | Scala | import java.util
object DoublyLinkedListTraversal extends App {
private val ll = new util.LinkedList[String]
private def traverse(iter: util.Iterator[String]) =
while (iter.hasNext) iter.next
traverse(ll.iterator)
traverse(ll.descendingIterator)
} | Give a code snippet in #Scala
Traverse from the beginning of a doubly-linked list to the end, and from the end to the beginning.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element R... | 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 ... | #Elena | Elena | import system'routines;
import extensions;
class Foo;
// create a list of disting object
fill(n)
= RangeEnumerator.new(1,n).selectBy:(x => new Foo()).toArray();
// testing
public program()
{
var foos := fill(10);
} | Give a code snippet in #Elena
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/Flow-control_structures | Flow-control structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
Document common flow-control structures.
One common example of a flow-control structure is the goto construct.
Note that Conditional Struc... | #Z80_Assembly | Z80 Assembly | PrintString:
ld a,(hl) ;HL is our pointer to the string we want to print
cp 0 ;it's better to use OR A to compare A to zero, but for demonstration purposes this is easier to read.
ret z ;return if accumulator = zero
call PrintChar ;prints accumulator's ascii code to screen - on Amstrad CPC f... | Give a code snippet in #Z80_Assembly
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
Document common flow-control structures.
One common example of a flow-control structure is the goto con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_composition | Function composition | Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function g to x.
Example
compose... | #AutoHotkey | AutoHotkey | MsgBox % compose("sin","cos",1.5)
compose(f,g,x) { ; function composition
Return %f%(%g%(x))
} | Give a code snippet in #AutoHotkey
Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_concatenation | String concatenation | String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string literal.
To illustrate the operat... | #Lambdatalk | Lambdatalk |
{def christian_name Albert}
-> christian_name
{def name de Jeumont-Schneidre}
-> name
{christian_name} {name}
-> Albert de Jeumont-Schneidre
| Give a code snippet in #Lambdatalk
String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another strin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Forward_difference | Forward difference | Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B should have one fewer elem... | #BQN | BQN | FDiff ← {{-˜´˘2↕𝕩}⍟𝕨 𝕩}
•Show 1 FDiff 90‿47‿58‿29‿22‿32‿55‿5‿55‿73
•Show 2 FDiff 90‿47‿58‿29‿22‿32‿55‿5‿55‿73 | Give a code snippet in #BQN
Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_join | Hash join | An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash join" algorithm, and demonstrate tha... | #Perl | Perl | use Data::Dumper qw(Dumper);
sub hashJoin {
my ($table1, $index1, $table2, $index2) = @_;
my %h;
# hash phase
foreach my $s (@$table1) {
push @{ $h{$s->[$index1]} }, $s;
}
# join phase
map { my $r = $_;
map [$_, $r], @{ $h{$r->[$index2]} }
} @$table2;
}
@table1 = ([27, "Jonah"],
... | Give a code snippet in #Perl
An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash join" ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multifactorial | Multifactorial | The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(... | #AWK | AWK |
# syntax: GAWK -f MULTIFACTORIAL.AWK
# converted from Go
BEGIN {
for (k=1; k<=5; k++) {
printf("degree %d:",k)
for (n=1; n<=10; n++) {
printf(" %d",multi_factorial(n,k))
}
printf("\n")
}
exit(0)
}
function multi_factorial(n,k, r) {
r = 1
for (; n>1; n-=k) {
r... | Give a code snippet in #AWK
The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_clock | Draw a clock | Task
Draw a clock.
More specific:
Draw a time keeping device. It can be a stopwatch, hourglass, sundial, a mouth counting "one thousand and one", anything. Only showing the seconds is required, e.g.: a watch with just a second hand will suffice. However, it must clearly change every second, and the change must cy... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "float.s7i";
include "math.s7i";
include "draw.s7i";
include "keybd.s7i";
include "time.s7i";
include "duration.s7i";
const integer: WINDOW_WIDTH is 200;
const integer: WINDOW_HEIGHT is 200;
const color: BACKGROUND is White;
const color: FOREGROUND is Black;
const color: ... | Give a code snippet in #Seed7
Task
Draw a clock.
More specific:
Draw a time keeping device. It can be a stopwatch, hourglass, sundial, a mouth counting "one thousand and one", anything. Only showing the seconds is required, e.g.: a watch with just a second hand will suffice. However, it must clearly change every... | 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... | #Common_Lisp | Common Lisp |
(print (length #("apple" "orange")))
| Give a code snippet in #Common_Lisp
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/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
| #ooRexx | ooRexx | /* Rexx */
say 'Hello world!'
| Give a code snippet in #ooRexx
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/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:... | #Racket | Racket | #lang racket/base
;; Racket's `directory-list' produces a sorted list of files
(define (ls) (for-each displayln (directory-list)))
;; Code to run when this file is running directly
(module+ main
(ls))
(module+ test
(require tests/eli-tester racket/port racket/file)
(define (make-directory-tree)
(make-di... | Give a code snippet in #Racket
Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Examp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Box_the_compass | Box the compass | There be many a land lubber that knows naught of the pirate ways and gives direction by degree!
They know not how to box the compass!
Task description
Create a function that takes a heading in degrees and returns the correct 32-point compass heading.
Use the function to print and display a table of Index, Compass... | #Ruby | Ruby | Headings = %w(north east south west north).each_cons(2).flat_map do |a, b|
[a,
"#{a} by #{b}",
"#{a}-#{a}#{b}",
"#{a}#{b} by #{a}",
"#{a}#{b}",
"#{a}#{b} by #{b}",
"#{b}-#{a}#{b}",
"#{b} by #{a}"]
end
Headings.prepend nil
def heading(degrees)
i = degrees.quo(360).*(32).round.%(32).+(1)
[i, Headin... | Give a code snippet in #Ruby
There be many a land lubber that knows naught of the pirate ways and gives direction by degree!
They know not how to box the compass!
Task description
Create a function that takes a heading in degrees and returns the correct 32-point compass heading.
Use the function to print and dis... | 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 .
| #Frink | Frink |
// Maximum levels for each pixel.
levels = 60
// Create a random color for each level.
colors = new array[[levels]]
for a = 0 to levels-1
colors@a = new color[randomFloat[0,1], randomFloat[0,1], randomFloat[0,1]]
// Make this number smaller for higher resolution.
stepsize = .005
g = new graphics
g.antialiase... | Give a code snippet in #Frink
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/Topswops | Topswops | Topswops is a card game created by John Conway in the 1970's.
Assume you have a particular permutation of a set of n cards numbered 1..n on both of their faces, for example the arrangement of four cards given by [2, 4, 1, 3] where the leftmost card is on top.
A round is composed of reversing the first ... | #Lua | Lua | -- Return an iterator to produce every permutation of list
function permute (list)
local function perm (list, n)
if n == 0 then coroutine.yield(list) end
for i = 1, n do
list[i], list[n] = list[n], list[i]
perm(list, n - 1)
list[i], list[n] = list[n], list[i]
... | Give a code snippet in #Lua
Topswops is a card game created by John Conway in the 1970's.
Assume you have a particular permutation of a set of n cards numbered 1..n on both of their faces, for example the arrangement of four cards given by [2, 4, 1, 3] where the leftmost card is on top.
A round is comp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Currying | Currying |
This page uses content from Wikipedia. The original article was at Currying. 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
Create a simple demonstrative example of Currying in a specific la... | #Java | Java | public class Currier<ARG1, ARG2, RET> {
public interface CurriableFunctor<ARG1, ARG2, RET> {
RET evaluate(ARG1 arg1, ARG2 arg2);
}
public interface CurriedFunctor<ARG2, RET> {
RET evaluate(ARG2 arg);
}
final CurriableFunctor<ARG1, ARG2, RET> functo... | Give a code snippet in #Java
This page uses content from Wikipedia. The original article was at Currying. 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
Create a simple demonstrative exampl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #Forth | Forth | : quaternions 4 * floats ;
: qvariable create 1 quaternions allot ;
: q! ( a b c d q -- )
dup 3 floats + f! dup 2 floats + f! dup float+ f! f! ;
: qcopy ( src dest -- ) 1 quaternions move ;
: qnorm ( q -- f )
0e 4 0 do dup f@ fdup f* f+ float+ loop drop fsqrt ;
: qf* ( q f -- )
4 0 do dup f@ fove... | Give a code snippet in #Forth
Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pragmatic_directives | Pragmatic directives | Pragmatic directives cause the language to operate in a specific manner, allowing support for operational variances within the program code (possibly by the loading of specific or alternative modules).
Task
List any pragmatic directives supported by the language, and demonstrate how to activate and deactivate... | #Python | Python | Python 3.2 (r32:88445, Feb 20 2011, 21:30:00) [MSC v.1500 64 bit (AMD64)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> import __future__
>>> __future__.all_feature_names
['nested_scopes', 'generators', 'division', 'absolute_import', 'with_statement', 'print_function', 'unicode_literals'... | Give a code snippet in #Python
Pragmatic directives cause the language to operate in a specific manner, allowing support for operational variances within the program code (possibly by the loading of specific or alternative modules).
Task
List any pragmatic directives supported by the language, and demonstrat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game | 24 game | The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T... | #Wren | Wren | import "random" for Random
import "/ioutil" for Input
import "/seq" for Stack
var R = Random.new()
class Game24 {
static run() {
var digits = List.filled(4, 0)
for (i in 0..3) digits[i] = R.int(1, 10)
System.print("Make 24 using these digits: %(digits)")
var cin = Input.text("> "... | Give a code snippet in #Wren
The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four dig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ascending_primes | Ascending primes | Generate and show all primes with strictly ascending decimal digits.
Aside: Try solving without peeking at existing solutions. I had a weird idea for generating
a prime sieve faster, which needless to say didn't pan out. The solution may be p(r)etty trivial
but generating them quickly is at least mildly interesting.
T... | #Quackery | Quackery | [ 0 swap witheach
[ swap 10 * + ] ] is digits->n ( [ --> n )
[]
' [ 1 2 3 4 5 6 7 8 9 ] powerset
witheach
[ digits->n dup isprime
iff join else drop ]
sort echo | Give a code snippet in #Quackery
Generate and show all primes with strictly ascending decimal digits.
Aside: Try solving without peeking at existing solutions. I had a weird idea for generating
a prime sieve faster, which needless to say didn't pan out. The solution may be p(r)etty trivial
but generating them quickly... | 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... | #Mercury | Mercury | :- module department_numbers.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is cc_multi.
:- implementation.
:- import_module int, list, solutions, string.
main(!IO) :-
io.print_line("P S F", !IO),
unsorted_aggregate(department_number, print_solution, !IO).
:- pred print_solution({int... | Give a code snippet in #Mercury
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 (... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix_transposition | Matrix transposition | Transpose an arbitrarily sized rectangular Matrix.
| #HicEst | HicEst | REAL :: mtx(2, 4)
mtx = 1.1 * $
WRITE() mtx
SOLVE(Matrix=mtx, Transpose=mtx)
WRITE() mtx | Give a code snippet in #HicEst
Transpose an arbitrarily sized rectangular Matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_manipulation | Date manipulation | Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| #Frink | Frink |
### MMM dd yyyy h:mma ###
d = parseDate["March 7 2009 7:30pm EST"]
println[d + 12 hours -> Eastern]
println[d + 12 hours -> Switzerland] // Extra credit
| Give a code snippet in #Frink
Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pentagram | Pentagram |
A pentagram is a star polygon, consisting of a central pentagon of which each side forms the base of an isosceles triangle. The vertex of each triangle, a point of the star, is 36 degrees.
Task
Draw (or print) a regular pentagram, in any orientation. Use a different color (or token) for stroke and fill, and backg... | #Red | Red | Red [
Source: https://github.com/vazub/rosetta-red
Tabs: 4
Needs: 'View
]
canvas: 500x500
center: as-pair canvas/x / 2 canvas/y / 2
radius: 200
points: collect [
repeat vertex 10 [
angle: vertex * 36 + 18 ;-- +18 is required for pentagram rotation
either vertex // 2 = 1 [
keep as-pair (co... | Give a code snippet in #Red
A pentagram is a star polygon, consisting of a central pentagon of which each side forms the base of an isosceles triangle. The vertex of each triangle, a point of the star, is 36 degrees.
Task
Draw (or print) a regular pentagram, in any orientation. Use a different color (or token) f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Output | Non-decimal radices/Output | Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routines of your programming langu... | #PL.2FI | PL/I |
get list (n);
put skip list (n); /* Prints N in decimal */
put skip edit (n) (B); /* prints N as a bit string, N > 0 */
| Give a code snippet in #PL.2FI
Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard ro... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #Ring | Ring |
rename("input.txt", "output.txt")
rename("docs", "mydocs")
rename("/input.txt", "/output.txt")
rename("/docs", "/mydocs")
| Give a code snippet in #Ring
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rig... | 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.
| #REBOL | REBOL | rebol [
Title: "Simple Windowed Application"
URL: http://rosettacode.org/wiki/Simple_Windowed_Application
]
clicks: 0
; Simple GUI's in REBOL can be defined with 'layout', a
; special-purpose language (dialect, in REBOL-speak) for specifying
; interfaces. In the example below, I describe a gradient background
; w... | Give a code snippet in #REBOL
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/Order_by_pair_comparisons | Order by pair comparisons |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #C | C | #include <stdio.h>
#include <string.h>
#include <stdlib.h>
int interactiveCompare(const void *x1, const void *x2)
{
const char *s1 = *(const char * const *)x1;
const char *s2 = *(const char * const *)x2;
static int count = 0;
printf("(%d) Is %s <, ==, or > %s? Answer -1, 0, or 1: ", ++count, s1, s2);
int re... | Give a code snippet in #C
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RPG_attributes_generator | RPG attributes generator | RPG = Role Playing Game.
You're running a tabletop RPG, and your players are creating characters.
Each character has six core attributes: strength, dexterity, constitution, intelligence, wisdom, and charisma.
One way of generating values for these attributes is to roll four, 6-sided dice (d6) and sum the three... | #Yabasic | Yabasic | sub d6()
//simulates a marked regular hexahedron coming to rest on a plane
return 1 + int(ran(6))
end sub
sub roll_stat()
//rolls four dice, returns the sum of the three highest
a = d6() : b = d6(): c = d6(): d = d6()
return a + b + c + d - min(min(a, b), min(c, d))
end sub
dim statnames$(6)
st... | Give a code snippet in #Yabasic
RPG = Role Playing Game.
You're running a tabletop RPG, and your players are creating characters.
Each character has six core attributes: strength, dexterity, constitution, intelligence, wisdom, and charisma.
One way of generating values for these attributes is to roll four, 6-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Josephus_problem | Josephus problem | Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
{\displaystyle 0}
,
removing eve... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | survivor[n_, k_] := Nest[Most[RotateLeft[#, k]] &, Range[0, n - 1], n - 1]
survivor[41, 3] | Give a code snippet in #Mathematica.2FWolfram_Language
Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Merging | Associative array/Merging | Task
Define two associative arrays, where one represents the following "base" data:
Key
Value
"name"
"Rocket Skates"
"price"
12.75
"color"
"yellow"
And the other represents "update" data:
Key
Value
"price"
15.25
"color"
"red"
"year"
1974
Merge these into a new associativ... | #11l | 11l | V base = [‘name’ = ‘Rocket Skates’, ‘price’ = ‘12.75’, ‘color’ = ‘yellow’]
V update = [‘price’ = ‘15.25’, ‘color’ = ‘red’, ‘year’ = ‘1974’]
V result = copy(base)
result.update(update)
print(result) | Give a code snippet in #11l
Task
Define two associative arrays, where one represents the following "base" data:
Key
Value
"name"
"Rocket Skates"
"price"
12.75
"color"
"yellow"
And the other represents "update" data:
Key
Value
"price"
15.25
"color"
"red"
"year"
1974
Merg... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pythagorean_triples | Pythagorean triples | A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime,... | #Nanoquery | Nanoquery | import math
// a function to check if three numbers are a valid triple
def is_triple(a, b, c)
if not (a < b) and (b < c)
return false
end
return (a^2 + b^2) = c^2
end
// a function to check if the numbers are coprime
def is_coprime(a, b, c)
global math
return (math.gcd(a, b)=1) && (mat... | Give a code snippet in #Nanoquery
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Disarium_numbers | Disarium numbers | A Disarium number is an integer where the sum of each digit raised to the power of its position in the number, is equal to the number.
E.G.
135 is a Disarium number:
11 + 32 + 53 == 1 + 9 + 125 == 135
There are a finite number of Disarium numbers.
Task
Find and display the first 18 Disarium numbers.
Stretch... | #Phix | Phix | with javascript_semantics
constant limit = 19
integer count = 0, n = 0
printf(1,"The first 19 Disarium numbers are:\n")
while count<limit do
atom dsum = 0
string digits = sprintf("%d",n)
for i=1 to length(digits) do
dsum += power(digits[i]-'0',i)
end for
if dsum=n then
printf(1," %d... | Give a code snippet in #Phix
A Disarium number is an integer where the sum of each digit raised to the power of its position in the number, is equal to the number.
E.G.
135 is a Disarium number:
11 + 32 + 53 == 1 + 9 + 125 == 135
There are a finite number of Disarium numbers.
Task
Find and display the first ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fast_Fourier_transform | Fast Fourier transform | Task
Calculate the FFT (Fast Fourier Transform) of an input sequence.
The most general case allows for complex numbers at the input
and results in a sequence of equal length, again of complex numbers.
If you need to restrict yourself to real numbers, the output should
be the magnitude (i.e.: sqrt(re2 + im2)... | #Sidef | Sidef | func fft(arr) {
arr.len == 1 && return arr
var evn = fft([arr[^arr -> grep { .is_even }]])
var odd = fft([arr[^arr -> grep { .is_odd }]])
var twd = (Num.tau.i / arr.len)
^odd -> map {|n| odd[n] *= ::exp(twd * n)}
(evn »+« odd) + (evn »-« odd)
}
var cycles = 3
var sequence = 0..15
var wave... | Give a code snippet in #Sidef
Task
Calculate the FFT (Fast Fourier Transform) of an input sequence.
The most general case allows for complex numbers at the input
and results in a sequence of equal length, again of complex numbers.
If you need to restrict yourself to real numbers, the output should
be the magni... | 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... | #Go.21 | Go! | --
-- 99 Bottles of Beer in Go!
-- John Knottenbelt
--
-- Go! is a multi-paradigm programming language that is oriented
-- to the needs of programming secure, production quality, agent
-- based applications.
--
-- http://www.doc.ic.ac.uk/~klc/dalt03.html
--
main .. {
include "sys:go/io.gof".
include "sys:... | Give a code snippet in #Go.21
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/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... | #Tcl | Tcl | package require Tk
set s "Hello World! "
set dir 0
# Periodic animation callback
proc animate {} {
global dir s
if {$dir} {
set s [string range $s 1 end][string index $s 0]
} else {
set s [string index $s end][string range $s 0 end-1]
}
# We will run this code ~8 times a second (== 1... | Give a code snippet in #Tcl
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 demo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_strings | Binary strings | Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according to Wikipedia) for those la... | #Red | Red | Red []
s: copy "abc" ;; string creation
s: none ;; destruction
t: "Abc"
if t == "abc" [print "equal case"] ;; comparison , case sensitive
if t = "abc" [print "equal (case insensitive)"] ;; comparison , case insensitive
s: copy "" ;; copying string
if empty? s [pr... | Give a code snippet in #Red
Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings accordi... | 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... | #Logo | Logo | make "size 100
make "white 1
make "black 2
make "sum sum :white :black
make "chars [. #]
make "origin quotient :size 2
make "grid mdarray (list :size :size)
make "directions [ [1 0] [0 1] [-1 0] [0 -1] ]
repeat size [
local "y
make "y repcount
repeat size [
mdsetitem (list repcount :y) :grid :white
]
]
m... | Give a code snippet in #Logo
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/Lucas-Lehmer_test | Lucas-Lehmer test | Lucas-Lehmer Test:
for
p
{\displaystyle p}
an odd prime, the Mersenne number
2
p
−
1
{\displaystyle 2^{p}-1}
is prime if and only if
2
p
−
1
{\displaystyle 2^{p}-1}
divides
S
(
p
−
1
)
{\displaystyle S(p-1)}
where
S
(
n
+
1
)
=
(
S
(
n
)
)
2
−
2
{\displaystyle S(n+1)=(... | #J | J | import java.math.BigInteger;
public class Mersenne
{
public static boolean isPrime(int p) {
if (p == 2)
return true;
else if (p <= 1 || p % 2 == 0)
return false;
else {
int to = (int)Math.sqrt(p);
for (int i = 3; i <= to; i += 2)
... | Give a code snippet in #J
Lucas-Lehmer Test:
for
p
{\displaystyle p}
an odd prime, the Mersenne number
2
p
−
1
{\displaystyle 2^{p}-1}
is prime if and only if
2
p
−
1
{\displaystyle 2^{p}-1}
divides
S
(
p
−
1
)
{\displaystyle S(p-1)}
where
S
(
n
+
1
)
=
(
S
(
n
)
)
2
−
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic | Bitmap/Bézier curves/Quadratic | Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve
(definition on Wikipedia).
| #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
proc Bezier(P0, P1, P2); \Draw quadratic Bezier curve
real P0, P1, P2;
def Segments = 8;
int I;
real T, A, B, C, X, Y;
[Move(fix(P0(0)), fix(P0(1)));
for I:= 1 to Segments do
[T:= float(I)/float(Segments);
A:= sq(1.-T);
B:... | Give a code snippet in #XPL0
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Jewels_and_stones | Jewels and stones | Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case letters. However, in the case ... | #Draco | Draco | proc nonrec count_jewels(*char jewels, stones) word:
[256] bool jewel;
word count;
byte i;
char c;
for i from 0 upto 255 do jewel[i] := false od;
while c := jewels*; c ~= '\e' do
jewel[c] := true;
jewels := jewels + 1;
od;
count := 0;
while c := stones*; c ~= '\e'... | Give a code snippet in #Draco
Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiplication_tables | Multiplication tables | Task
Produce a formatted 12×12 multiplication table of the kind memorized by rote when in primary (or elementary) school.
Only print the top half triangle of products.
| #EchoLisp | EchoLisp |
(lib 'matrix)
(define (mtable i j)
(cond
((and (zero? i) (zero? j)) "😅")
((= i 0) j)
((= j 0) i)
((>= j i ) (* i j ))
(else " ")))
(array-print (build-array 13 13 mtable))
| Give a code snippet in #EchoLisp
Task
Produce a formatted 12×12 multiplication table of the kind memorized by rote when in primary (or elementary) school.
Only print the top half triangle of products.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Universal_Turing_machine | Universal Turing machine | One of the foundational mathematical constructs behind computer science
is the universal Turing Machine.
(Alan Turing introduced the idea of such a machine in 1936–1937.)
Indeed one way to definitively prove that a language
is turing-complete
is to implement a universal Turing machine in it.
Task
Simulate such ... | #Haskell | Haskell | -- Some elementary types for Turing Machine
data Move = MLeft | MRight | Stay deriving (Show, Eq)
data Tape a = Tape a [a] [a]
data Action state val = Action val Move state deriving (Show)
instance (Show a) => Show (Tape a) where
show (Tape x lts rts) = concat $ left ++ [hd] ++ right
where... | Give a code snippet in #Haskell
One of the foundational mathematical constructs behind computer science
is the universal Turing Machine.
(Alan Turing introduced the idea of such a machine in 1936–1937.)
Indeed one way to definitively prove that a language
is turing-complete
is to implement a universal Turing machi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_arithmetic | Modular arithmetic | Modular arithmetic is a form of arithmetic (a calculation technique involving the concepts of addition and multiplication) which is done on numbers with a defined equivalence relation called congruence.
For any positive integer
p
{\displaystyle p}
called the congruence modulus,
two numbers
a
{\displaysty... | #Haskell | Haskell | -- We use a couple of GHC extensions to make the program cooler. They let us
-- use / as an operator and 13 as a literal at the type level. (The library
-- also provides the fancy Zahlen (ℤ) symbol as a synonym for Integer.)
{-# Language DataKinds #-}
{-# Language TypeOperators #-}
import Data.Modular
f :: ℤ/13... | Give a code snippet in #Haskell
Modular arithmetic is a form of arithmetic (a calculation technique involving the concepts of addition and multiplication) which is done on numbers with a defined equivalence relation called congruence.
For any positive integer
p
{\displaystyle p}
called the congruence modulus,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/Floating_point | Literals/Floating point | Programming languages have different ways of expressing floating-point literals.
Task
Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features.
You may want to include a regular expression or BNF/ABNF/EBNF defining allowable fo... | #Swift | Swift | let double = 1.0 as Double // Double precision
let float = 1.0 as Float // Single precision
let scientific = 1.0E-12
// Swift does not feature type coercion for explicit type declaration
let sum = double + float // Error
let div = 1.1 / 2 // Double
let div1 = 1 / 2 // 0 | Give a code snippet in #Swift
Programming languages have different ways of expressing floating-point literals.
Task
Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features.
You may want to include a regular expression or BNF/... | 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... | #Gambas | Gambas | 'This code will create a GUI Form to display the result
hGridView As GridView 'The display is on a GridView
iCol As Integer = 38 'Column start position
iRow As Integer = 30 'Row ... | Give a code snippet in #Gambas
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 th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sexy_primes | Sexy primes |
This page uses content from Wikipedia. The original article was at Sexy_prime. 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 mathematics, sexy primes are prime numbers that differ from each ot... | #Nim | Nim | import math, strformat, strutils
const Lim = 1_000_035
type Group {.pure.} = enum # "ord" gives the number of terms.
Unsexy = (1, "unsexy primes")
Pairs = (2, "sexy prime pairs")
Triplets = (3, "sexy prime triplets")
Quadruplets = (4, "sexy prime quadruplets")
Quintuplets = (5, "sexy prime quintupl... | Give a code snippet in #Nim
This page uses content from Wikipedia. The original article was at Sexy_prime. 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 mathematics, sexy primes are prime num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic | Bitmap/Bézier curves/Quadratic | Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve
(definition on Wikipedia).
| #Python | Python |
#lang racket
(require racket/draw)
(define (draw-line dc p q)
(match* (p q) [((list x y) (list s t)) (send dc draw-line x y s t)]))
(define (draw-lines dc ps)
(void
(for/fold ([p0 (first ps)]) ([p (rest ps)])
(draw-line dc p0 p)
p)))
(define (int t p q)
(define ((int1 t) x0 x1) (+ (* (- 1 t) ... | Give a code snippet in #Python
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Mad_Libs | Mad Libs |
This page uses content from Wikipedia. The original article was at Mad Libs. 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)
Mad Libs is a phrasal template word game where one player prompts another... | #Perl | Perl | #!/usr/bin/perl
use warnings;
use strict;
my $template = shift;
open my $IN, '<', $template or die $!;
my $story = do { local $/ ; <$IN> };
my %blanks;
undef $blanks{$_} for $story =~ m/<(.*?)>/g;
for my $blank (sort keys %blanks) {
print "$blank: ";
chomp (my $replacement = <>);
$blanks{$blank} = $re... | Give a code snippet in #Perl
This page uses content from Wikipedia. The original article was at Mad Libs. 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)
Mad Libs is a phrasal template word game wh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_non-squares | Sequence of non-squares | Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
| #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
func real Floor(X); \Truncate X toward - infinity
real X;
return float(fix(X-0.5));
func PerfectSq(N); \Return 'true' if N is a perfect square
int N;
return sqrt(N)*sqrt(N) = N;
int N, M, M0;
[for N:= 1 to 22 do
[IntOu... | Give a code snippet in #XPL0
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Huffman_coding | Huffman coding | Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi... | #Ruby | Ruby | require 'priority_queue'
def huffman_encoding(str)
char_count = Hash.new(0)
str.each_char {|c| char_count[c] += 1}
pq = CPriorityQueue.new
# chars with fewest count have highest priority
char_count.each {|char, count| pq.push(char, count)}
while pq.length > 1
key1, prio1 = pq.delete_min
key2, ... | Give a code snippet in #Ruby
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you co... | 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 ... | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program fcttime.s */
/* Constantes */
.equ STDOUT, 1 @ Linux output console
.equ EXIT, 1 @ Linux syscall
.equ WRITE, 4 @ Linux syscall
.equ N1, 1000000 @ loop number
.equ NBMEASURE, 10 @ measure number
/*********************************/
/* Initialized ... | Give a code snippet in #ARM_Assembly
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
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Happy_numbers | Happy numbers | From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not inclu... | #Ursala | Ursala | #import std
#import nat
happy = ==1+ ^== sum:-0+ product*iip+ %np*hiNCNCS+ %nP
first "p" = ~&i&& iota; ~&lrtPX/&; leql@lrPrX->lrx ^|\~& ^/successor@l ^|T\~& "p"&& ~&iNC
#cast %nL
main = (first happy) 8 | Give a code snippet in #Ursala
From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Graphical | Hello world/Graphical |
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| #mIRC_Scripting_Language | mIRC Scripting Language | alias goodbyegui {
dialog -m Goodbye Goodbye
}
dialog Goodbye {
title "Goodbye, World!"
size -1 -1 80 20
option dbu
text "Goodbye, World!", 1, 20 6 41 7
} | Give a code snippet in #mIRC_Scripting_Language
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Nautical_bell | Nautical bell |
Task
Write a small program that emulates a nautical bell producing a ringing bell pattern at certain times throughout the day.
The bell timing should be in accordance with Greenwich Mean Time, unless locale dictates otherwise.
It is permissible for the program to daemonize, or to slave off a scheduler, and it is per... | #Ruby | Ruby | watches = [ "First", "Middle", "Morning", "Forenoon", "Afternoon", "First dog", "Last dog", "First" ]
watch_ends = [ "00:00", "04:00", "08:00", "12:00", "16:00", "18:00", "20:00", "23:59" ]
words = ["One","Two","Three","Four","Five","Six","Seven","Eight"]
sound = "ding!"
loop do
time = Time.now
if time.sec == 0 a... | Give a code snippet in #Ruby
Task
Write a small program that emulates a nautical bell producing a ringing bell pattern at certain times throughout the day.
The bell timing should be in accordance with Greenwich Mean Time, unless locale dictates otherwise.
It is permissible for the program to daemonize, or to slave ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Forest_fire | Forest fire |
This page uses content from Wikipedia. The original article was at Forest-fire model. 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
Implement the Drossel and Schwabl definition of the fores... | #C.23 | C# | using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Threading;
using System.Windows.Forms;
namespace ForestFire
{
class Program : Form
{
private static readonly Random rand = new Random();
private Bitmap img;
public Program(int w, int h, int f, int p)
... | Give a code snippet in #C.23
This page uses content from Wikipedia. The original article was at Forest-fire model. 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
Implement the Drossel and S... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_to_100 | Sum to 100 | Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular sum (in this iconic case, ... | #C.2B.2B | C++ | /*
* RossetaCode: Sum to 100, C++, STL, OOP.
* Works with: MSC 16.0 (MSVS2010); GCC 5.1 (use -std=c++11 or -std=c++14 etc.).
*
* Find solutions to the "sum to one hundred" puzzle.
*/
#include <iostream>
#include <iomanip>
#include <algorithm>
#include <string>
#include <set>
#include <map>
using namespace std;... | Give a code snippet in #C.2B.2B
Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particul... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Enumerations | Enumerations | Task
Create an enumeration of constants with and without explicit values.
| #JScript.NET | JScript.NET | enum fruits { apple, banana, cherry }
enum fruits { apple = 0, banana = 1, cherry = 2 } | Give a code snippet in #JScript.NET
Task
Create an enumeration of constants with and without explicit values.
| 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 |... | #UNIX_Shell | UNIX Shell | #!/bin/sh
A=Bell
B=Ball
# Traditional test command implementations test for equality and inequality
# but do not have a lexical comparison facility
if [ $A = $B ] ; then
echo 'The strings are equal'
fi
if [ $A != $B ] ; then
echo 'The strings are not equal'
fi
# All variables in the shell are strings, so nume... | Give a code snippet in #UNIX_Shell
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 Operat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/General_FizzBuzz | General FizzBuzz | Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be ... | #AutoHotkey | AutoHotkey | ; Test parameters
max := 20, fizz := 3, buzz := 5, baxx := 7
Loop % max {
output := ""
if (Mod(A_Index, fizz) = 0)
output .= "Fizz"
if (Mod(A_Index, buzz) = 0)
output .= "Buzz"
if (Mod(A_Index, baxx) = 0)
output .= "Baxx"
if (output = "")
FileAppend %A_Index%`n, *
else
FileAppend %output%`n, *
}
| Give a code snippet in #AutoHotkey
Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated alon... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Old_Russian_measure_of_length | Old Russian measure of length | Task
Write a program to perform a conversion of the old Russian measures of length to the metric system (and vice versa).
It is an example of a linear transformation of several variables.
The program should accept a single value in a selected unit of measurement, and convert and return it to the other units:
... | #Ring | Ring |
# Project : Old Russian measure of length
decimals(7)
units = ["tochka", "liniya", "dyuim", "vershok", "piad", "fut",
"arshin", "sazhen", "versta", "milia",
"centimeter", "meter", "kilometer"]
convs = [0.0254, 0.254, 2.54, 4.445, 17.78, 30.48,
71.12, 213.36, 10668, 74676,... | Give a code snippet in #Ring
Task
Write a program to perform a conversion of the old Russian measures of length to the metric system (and vice versa).
It is an example of a linear transformation of several variables.
The program should accept a single value in a selected unit of measurement, and convert and r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Universal_Turing_machine | Universal Turing machine | One of the foundational mathematical constructs behind computer science
is the universal Turing Machine.
(Alan Turing introduced the idea of such a machine in 1936–1937.)
Indeed one way to definitively prove that a language
is turing-complete
is to implement a universal Turing machine in it.
Task
Simulate such ... | #EDSAC_order_code | EDSAC order code |
[Attempt at Turing machine for Rosetta Code.]
[EDSAC program, Initial Orders 2.]
[Library subroutine M3 prints header and is then overwritten.]
PFGKIFAFRDLFUFOFE@A6FG@E8FEZPF
*!!NR!STEPS@&#..PZ [..PZ marks end of header]
T48K [& (delta) parameter: Turing machine tape.]
... | Give a code snippet in #EDSAC_order_code
One of the foundational mathematical constructs behind computer science
is the universal Turing Machine.
(Alan Turing introduced the idea of such a machine in 1936–1937.)
Indeed one way to definitively prove that a language
is turing-complete
is to implement a universal Tur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Short-circuit_evaluation | Short-circuit evaluation | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable resources without side effects, an... | #D | D | import std.stdio, std.algorithm;
T a(T)(T answer) {
writefln(" # Called function a(%s) -> %s", answer, answer);
return answer;
}
T b(T)(T answer) {
writefln(" # Called function b(%s) -> %s", answer, answer);
return answer;
}
void main() {
foreach (immutable x, immutable y;
[fals... | Give a code snippet in #D
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable resourc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix_multiplication | Matrix multiplication | Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| #Ela | Ela | open list
mmult a b = [ [ sum $ zipWith (*) ar bc \\ bc <- (transpose b) ] \\ ar <- a ]
[[1, 2],
[3, 4]] `mmult` [[-3, -8, 3],
[-2, 1, 4]] | Give a code snippet in #Ela
Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| 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.)
| #Erlang | Erlang | % Erlang comments begin with "%" and extend to the end of the line. | Give a code snippet in #Erlang
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/State_name_puzzle | State name puzzle | Background
This task is inspired by Mark Nelson's DDJ Column "Wordplay" and one of the weekly puzzle challenges from Will Shortz on NPR Weekend Edition [1] and originally attributed to David Edelheit.
The challenge was to take the names of two U.S. States, mix them all together, then rearrange the letters to form the... | #Tcl | Tcl | package require Tcl 8.5
# Gödel number generator
proc goedel s {
set primes {
2 3 5 7 11 13 17 19 23 29 31 37 41
43 47 53 59 61 67 71 73 79 83 89 97 101
}
set n 1
foreach c [split [string toupper $s] ""] {
if {![string is alpha $c]} continue
set n [expr {$n * [lindex $primes [expr {[scan $c %c] - 65... | Give a code snippet in #Tcl
Background
This task is inspired by Mark Nelson's DDJ Column "Wordplay" and one of the weekly puzzle challenges from Will Shortz on NPR Weekend Edition [1] and originally attributed to David Edelheit.
The challenge was to take the names of two U.S. States, mix them all together, then rear... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Element_definition | Doubly-linked list/Element definition | Task
Define the data structure for a doubly-linked list element.
The element should include a data member to hold its value and pointers to both the next element in the list and the previous element in the list.
The pointers should be mutable.
See also
Array
Associative array: Creation, Iteration
Collections
... | #Nim | Nim | type
Node[T] = ref TNode[T]
TNode[T] = object
next, prev: Node[T]
data: T | Give a code snippet in #Nim
Task
Define the data structure for a doubly-linked list element.
The element should include a data member to hold its value and pointers to both the next element in the list and the previous element in the list.
The pointers should be mutable.
See also
Array
Associative array: Crea... | 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... | #XLISP | XLISP | (vector-length #("apple" "orange")) | Give a code snippet in #XLISP
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 frequ... | 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... | #Scala | Scala | object Eval extends App {
def evalWithX(expr: String, a: Double, b: Double)=
{val x = b; eval(expr)} - {val x = a; eval(expr)}
println(evalWithX("Math.exp(x)", 0.0, 1.0))
} | Give a code snippet in #Scala
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/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 ... | #MATLAB_.2F_Octave | MATLAB / Octave | function t = mean_time_of_day(t)
c = pi/(12*60*60);
for k=1:length(t)
a = sscanf(t{k},'%d:%d:%d');
phi(k) = (a(1)*3600+a(2)*60+a(3));
end;
d = angle(mean(exp(i*phi*c)))/(2*pi); % days
if (d<0) d += 1;
t = datestr(d,"HH:MM:SS");
end; | Give a code snippet in #MATLAB_.2F_Octave
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 usin... | 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... | #JavaScript_.2B_HTML | JavaScript + HTML | <html> <head>
<title>RC: Basic Animation</title>
<script type="text/javascript">
function animate(id) {
var element = document.getElementById(id);
var textNode = element.childNodes[0]; // assuming no other children
var text = textNode.data;
var reverse =... | Give a code snippet in #JavaScript_.2B_HTML
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. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/General_FizzBuzz | General FizzBuzz | Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be ... | #Clojure | Clojure | (defn fix [pairs]
(map second pairs))
(defn getvalid [pairs n]
(filter (fn [p] (zero? (mod n (first p))))
(sort-by first pairs)))
(defn gfizzbuzz [pairs numbers]
(interpose "\n"
(map (fn [n] (let [f (getvalid pairs n)]
(if (empty? f)
... | Give a code snippet in #Clojure
Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along w... | 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 ... | #Elena | Elena | public program()
{
var 四十二 := "♥♦♣♠"; // UTF8 string
var строка := "Привет"w; // UTF16 string
console.writeLine:строка;
console.writeLine:四十二;
} | Give a code snippet in #Elena
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inverted_index | Inverted index | An Inverted Index is a data structure used to create full text search.
Task
Given a set of text files, implement a program to create an inverted index.
Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms.
The search index can be i... | #Raku | Raku | sub MAIN (*@files) {
my %norm;
do for @files -> $file {
%norm.push: $file X=> slurp($file).lc.words;
}
(my %inv).push: %norm.invert.unique;
while prompt("Search terms: ").words -> @words {
for @words -> $word {
say "$word => {%inv.{$word.lc}//'(not found)'}";
}
... | Give a code snippet in #Raku
An Inverted Index is a data structure used to create full text search.
Task
Given a set of text files, implement a program to create an inverted index.
Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / ter... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (i... | #Mercury | Mercury | :- module query.
:- interface.
:- pred query(string::in, string::out) is det.
:- implementation.
query(_, "Hello, world!").
:- pragma foreign_export("C", query(in, out), "query").
:- pragma foreign_decl("C",
"
#include <string.h>
int Query (char * Data, size_t * Length);
").
:- pragma foreign_code("C",
"
int ... | Give a code snippet in #Mercury
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Topswops | Topswops | Topswops is a card game created by John Conway in the 1970's.
Assume you have a particular permutation of a set of n cards numbered 1..n on both of their faces, for example the arrangement of four cards given by [2, 4, 1, 3] where the leftmost card is on top.
A round is composed of reversing the first ... | #Picat | Picat | go ?=>
member(N,1..10),
Perm = 1..N,
Rev = Perm.reverse(),
Max = 0,
while(Perm != Rev)
next_permutation(Perm),
C = topswops(Perm),
if C > Max then
Max := C
end
end,
printf("%2d: %2d\n",N,Max),
fail,
nl.
go => true.
topswops([]) = 0 => true.
topswops([1]) = 0 => true.
topswop... | Give a code snippet in #Picat
Topswops is a card game created by John Conway in the 1970's.
Assume you have a particular permutation of a set of n cards numbered 1..n on both of their faces, for example the arrangement of four cards given by [2, 4, 1, 3] where the leftmost card is on top.
A round is co... | 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.... | #UNIX_Shell | UNIX Shell | # Program to determine the smallest positive integer whose square
# has a decimal representation ending in the digits 269,696.
# Start with the smallest positive integer of them all
let trial_value=1
# Compute the remainder when the square of the current trial value is divided
# by 1,000,000.␣
while (( trial_value ... | Give a code snippet in #UNIX_Shell
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Huffman_coding | Huffman coding | Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi... | #Swift | Swift | enum HuffmanTree<T> {
case Leaf(T)
indirect case Node(HuffmanTree<T>, HuffmanTree<T>)
func printCodes(prefix: String) {
switch(self) {
case let .Leaf(c):
print("\(c)\t\(prefix)")
case let .Node(l, r):
l.printCodes(prefix + "0")
r.printCodes(prefix + "1")
}
}
}
func buildTre... | Give a code snippet in #Swift
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #PL.2FI | PL/I |
declare in file, out file;
open file (in) title ('/INPUT.TXT,type(text),recsize(100)') input;
open file (out) title ('/OUTPUT.TXT,type(text),recsize(100') output;
do forever;
get file (in) edit (line) (L);
put file (out) edit (line) (A);
end;
| Give a code snippet in #PL.2FI
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file ... | 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... | #RLaB | RLaB |
>> x = sqrt(-1)
0 + 1i
>> y = 10 + 5i
10 + 5i
>> z = 5*x-y
-10 + 0i
>> isreal(z)
1
| Give a code snippet in #RLaB
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
{\displaysty... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animate_a_pendulum | Animate a pendulum |
One good way of making an animation is by simulating a physical system and illustrating the variables in that system using a dynamically changing graphical display.
The classic such physical system is a simple gravity pendulum.
Task
Create a simple physical model of a pendulum and animate it.
| #Perl | Perl |
use strict;
use warnings;
use Tk;
use Math::Trig qw/:pi/;
my $root = new MainWindow( -title => 'Pendulum Animation' );
my $canvas = $root->Canvas(-width => 320, -height => 200);
my $after_id;
for ($canvas) {
$_->createLine( 0, 25, 320, 25, -tags => [qw/plate/], -width => 2, -fill => 'grey50' );
$_->create... | Give a code snippet in #Perl
One good way of making an animation is by simulating a physical system and illustrating the variables in that system using a dynamically changing graphical display.
The classic such physical system is a simple gravity pendulum.
Task
Create a simple physical model of a pendulum and an... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comments | Comments | Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| #Apex | Apex |
System.debug ('I will execute'); // This comment is ignored.
/*
I am a large comment, completely ignored as well.
*/
| Give a code snippet in #Apex
Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/The_Twelve_Days_of_Christmas | The Twelve Days of Christmas | Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:
Metrics
Array length
Stri... | #CLU | CLU | christmas = cluster is carol
rep = null
own ordinals: array[string] := array[string]$[
"first", "second", "third", "fourth", "fifth",
"sixth", "seventh", "eighth", "ninth", "tenth",
"eleventh", "twelfth"
]
own gifts: array[string] := array[string]$[
"A partridge in a ... | Give a code snippet in #CLU
Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Attractive_numbers | Attractive numbers | A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
Show sequence items up to 120.... | #REXX | REXX | /*REXX program finds and shows lists (or counts) attractive numbers up to a specified N.*/
parse arg N . /*get optional argument from the C.L. */
if N=='' | N=="," then N= 120 /*Not specified? Then use the default.*/
cnt= N<0 ... | Give a code snippet in #REXX
A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
Sh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ABC_problem | ABC problem | ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet is guaranteed amongst all sid... | #SPAD | SPAD |
blocks:List Tuple Symbol:= _
[(B,O),(X,K),(D,Q),(C,P),(N,A),(G,T),(R,E),(T,G),(Q,D),(F,S), _
(J,W),(H,U),(V,I),(A,N),(O,B),(E,R),(F,S),(L,Y),(P,C),(Z,M)]
findComb(l:List List NNI):List List NNI ==
#l=0 => []
#l=1 => [[s] for s in first l]
r:List List NNI:=[]
for y in findComb(rest l) repeat
r:=co... | Give a code snippet in #SPAD
ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Symmetric_difference | Symmetric difference | Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{\displaystyle (A\cup B)\setminus (A... | #Rust | Rust | use std::collections::HashSet;
fn main() {
let a: HashSet<_> = ["John", "Bob", "Mary", "Serena"]
.iter()
.collect();
let b = ["Jim", "Mary", "John", "Bob"]
.iter()
.collect();
let diff = a.symmetric_difference(&b);
println!("{:?}", diff);
}
| Give a code snippet in #Rust
Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{\disp... | 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... | #VBScript | VBScript |
Dim sieve()
If WScript.Arguments.Count>=1 Then
n = WScript.Arguments(0)
Else
n = 99
End If
ReDim sieve(n)
For i = 1 To n
sieve(i) = True
Next
For i = 2 To n
If sieve(i) Then
For j = i * 2 To n Step i
sieve(j) = False
Next
... | Give a code snippet in #VBScript
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/Roots_of_a_function | Roots of a function | Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| #Tcl | Tcl | proc froots {lambda {start -3} {end 3} {step 0.0001}} {
set res {}
set lastsign [sgn [apply $lambda $start]]
for {set x $start} {$x <= $end} {set x [expr {$x + $step}]} {
set sign [sgn [apply $lambda $x]]
if {$sign != $lastsign} {
lappend res [format ~%.11f $x]
}
... | Give a code snippet in #Tcl
Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For | Loops/For | “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers.
... | #Perl | Perl | for(my $x = 1; $x <= 5; $x++) {
for(my $y = 1; $y <= $x; $y++) {
print "*";
}
print "\n";
} | Give a code snippet in #Perl
“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #M2000_Interpreter | M2000 Interpreter |
Module CheckIt {
Class FASTA_MACHINE {
Events "GetBuffer", "header", "DataLine", "Quit"
Public:
Module Run {
Const lineFeed$=chr$(13)+chr$(10)
Const WhiteSpace$=" "+chr$(9)+chrcode$(160)
Def long state=1, idstate=1
... | Give a code snippet in #M2000_Interpreter
In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such... | christopher/rosetta-code |
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