task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Anagrams | Anagrams | When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words in them.
Related tasks
Word plays
... | #Pointless | Pointless | output =
readFileLines("unixdict.txt")
|> reduce(logWord, {})
|> vals
|> getMax
|> printLines
logWord(dict, word) =
(dict with $[chars] = [word] ++ getDefault(dict, [], chars))
where chars = sort(word)
getMax(groups) =
groups |> filter(g => length(g) == maxLength)
where maxLength = groups |> map(l... | Give a code snippet in #Pointless
When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #C.23 | C# | using System;
using System.IO;
namespace RosettaCode {
class Program {
static void Main() {
try {
File.Delete("input.txt");
Directory.Delete("docs");
File.Delete(@"\input.txt");
Directory.Delete(@"\docs");
} catch (Exc... | Give a code snippet in #C.23
Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Boolean_values | Boolean values | Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| #Oforth | Oforth | my $x = 0.0;
my $true_or_false = $x ? 'true' : 'false'; # false | Give a code snippet in #Oforth
Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Conditional_structures | Conditional structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common conditional structures include ... | #Modula-3 | Modula-3 | IF Foo = TRUE THEN
Bar();
ELSE
Baz();
END; | Give a code snippet in #Modula-3
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Comm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Modula-2 | Modula-2 | MODULE Main;
BEGIN
END Main. | Give a code snippet in #Modula-2
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort | Sorting algorithms/Cocktail sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #C.23 | C# | public static void cocktailSort(int[] A)
{
bool swapped;
do
{
swapped = false;
for (int i = 0; i <= A.Length - 2; i++)
{
if (A[i] > A[i + 1])
{
//test whether the two elements are in the wrong order
... | Give a code snippet in #C.23
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Archimedean_spiral | Archimedean spiral |
The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.
An Archimedean spiral can be described by the equation:
r
=
a
+
b
θ
{\displaystyle \,r=a+b\theta }
with real numbers a and b.
Task
Draw an Archimedean spiral.
| #Quackery | Quackery | [ $ "turtleduck.qky" loadfile ] now!
turtle
0 n->v
900 times
[ 2dup walk
1 20 v+
1 36 turn ]
2drop | Give a code snippet in #Quackery
The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.
An Archimedean spiral can be described by the equation:
r
=
a
+
b
θ
{\displaystyle \,r=a+b\theta }
with real numbers a and b.
Task
Draw an Archimedean spiral.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #PHP | PHP | function perpendicular_distance(array $pt, array $line) {
// Calculate the normalized delta x and y of the line.
$dx = $line[1][0] - $line[0][0];
$dy = $line[1][1] - $line[0][1];
$mag = sqrt($dx * $dx + $dy * $dy);
if ($mag > 0) {
$dx /= $mag;
$dy /= $mag;
}
// Calculate dot product, projecting ... | Give a code snippet in #PHP
Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #BBC_BASIC | BBC BASIC | MAXITEMS = 100
FOR i% = 1 TO 8
READ n
PRINT "Value = "; n ", running SD = " FNrunningsd(n)
NEXT
END
DATA 2,4,4,4,5,5,7,9
DEF FNrunningsd(n)
PRIVATE list(), i%
DIM list(MAXITEMS)
i% += 1
list(i%) = n
= SQR(MOD(list())^2/i% - (SUM(list(... | Give a code snippet in #BBC_BASIC
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zumkeller_numbers | Zumkeller numbers | Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divisors are partitioned, only that ... | #Vlang | Vlang | fn get_divisors(n int) []int {
mut divs := [1, n]
for i := 2; i*i <= n; i++ {
if n%i == 0 {
j := n / i
divs << i
if i != j {
divs << j
}
}
}
return divs
}
fn sum(divs []int) int {
mut sum := 0
for div in divs {
... | Give a code snippet in #Vlang
Zumkeller numbers are the set of numbers whose divisors can be partitioned into two disjoint sets that sum to the same value. Each sum must contain divisor values that are not in the other sum, and all of the divisors must be in one or the other. There are no restrictions on how the divis... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm | Bitmap/Bresenham's line algorithm | Task
Using the data storage type defined on the Bitmap page for raster graphics images,
draw a line given two points with Bresenham's line algorithm.
| #AutoIt | AutoIt | Local $var = drawBresenhamLine(2, 3, 2, 6)
Func drawBresenhamLine($iX0, $iY0, $iX1, $iY1)
Local $iDx = Abs($iX1 - $iX0)
Local $iSx = $iX0 < $iX1 ? 1 : -1
Local $iDy = Abs($iY1 - $iY0)
Local $iSy = $iY0 < $iY1 ? 1 : -1
Local $iErr = ($iDx > $iDy ? $iDx : -$iDy) / 2, $e2
While $iX0 <= $iX1
ConsoleWrite("plot(... | Give a code snippet in #AutoIt
Task
Using the data storage type defined on the Bitmap page for raster graphics images,
draw a line given two points with Bresenham's line algorithm.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Collections | Collections | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create a collection, and add a fe... | #Logo | Logo | collection = {0, '1'}
print(collection[1]) -- prints 0
collection = {["foo"] = 0, ["bar"] = '1'} -- a collection of key/value pairs
print(collection["foo"]) -- prints 0
print(collection.foo) -- syntactic sugar, also prints 0
collection = {0, '1', ["foo"] = 0, ["bar"] = '1'} | Give a code snippet in #Logo
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Cre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop body... | #E | E | for i in (0..10).descending() { println(i) } | Give a code snippet in #E
Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/While | Loops/While | Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For... | #HolyC | HolyC | U16 i = 1024;
while (i > 0) {
Print("%d\n", i);
i /= 2;
} | Give a code snippet in #HolyC
Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downwar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Casting_out_nines | Casting out nines | Task (in three parts)
Part 1
Write a procedure (say
c
o
9
(
x
)
{\displaystyle {\mathit {co9}}(x)}
) which implements Casting Out Nines as described by returning the checksum for
x
{\displaystyle x}
. Demonstrate the procedure using the examples given there, or others you may consider lucky.
Par... | #Perl | Perl | sub co9 { # Follows the simple procedure asked for in Part 1
my $n = shift;
return $n if $n < 10;
my $sum = 0; $sum += $_ for split(//,$n);
co9($sum);
}
sub showadd {
my($n,$m) = @_;
print "( $n [",co9($n),"] + $m [",co9($m),"] ) [",co9(co9($n)+co9($m)),"]",
" = ", $n+$m," [",co9($n+$m),"]\n... | Give a code snippet in #Perl
Task (in three parts)
Part 1
Write a procedure (say
c
o
9
(
x
)
{\displaystyle {\mathit {co9}}(x)}
) which implements Casting Out Nines as described by returning the checksum for
x
{\displaystyle x}
. Demonstrate the procedure using the examples given there, or other... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)... | #Racket | Racket | #lang racket
;; A triangle is a list of three pairs of points: '((x . y) (x . y) (x . y))
(define (to-tri x1 y1 x2 y2 x3 y3) `((,x1 . ,y1) (,x2 . ,y2) (,x3 . ,y3)))
(define det-2D
(match-lambda
[`((,x1 . ,y1) (,x2 . ,y2) (,x3 . ,y3)) (+ (* x1 (- y2 y3)) (* x2 (- y3 y1)) (* x3 (- y1 y2)))]))
(define (assert-... | Give a code snippet in #Racket
Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ... | #Quackery | Quackery | [ over 3 mod 1 = ] is 1? ( n1 n2 --> n1 n2 f )
[ 3 / swap ] is 3/ ( n1 n2 --> n2/3 n1 )
[ true unrot
[ 2dup or while
1? 1? and iff
[ rot not unrot ] done
3/ 3/ again ]
2drop ] is incarpet ( n --> )
[... | Give a code snippet in #Quackery
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # #... | 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... | #UNIX_Shell | UNIX Shell | # choose 'choice 1' 'choice 2' ...
# Prints menu to standard error. Prompts with PS3.
# Reads REPLY from standard input. Sets CHOICE.
choose() {
CHOICE= # Default CHOICE is empty string.
[[ $# -gt 0 ]] || return # Return if "$@" is empty.
select CHOICE; do # Select from ... | Give a code snippet in #UNIX_Shell
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/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Scala | Scala | import java.io.IOException
import java.net.{InetAddress, ServerSocket}
object SingletonApp extends App {
private val port = 65000
try {
val s = new ServerSocket(port, 10, InetAddress.getLocalHost)
}
catch {
case _: IOException =>
// port taken, so app is already running
println("Applicat... | Give a code snippet in #Scala
This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Permutation_sort | Sorting algorithms/Permutation 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
... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
import java.util.List
import java.util.ArrayList
numeric digits 20
class RSortingPermutationsort public
properties private static
iterations
maxIterations
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~... | Give a code snippet in #NetRexx
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/Modified_random_distribution | Modified random distribution | Given a random number generator, (rng), generating numbers in the range 0.0 .. 1.0 called rgen, for example; and a function modifier(x)
taking an number in the same range and generating the probability that the input should be generated, in the same range 0..1; then implement the following algorithm for generating rand... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | ClearAll[Modifier, CreateRandomNumber]
Modifier[x_] := If[x < 0.5, 2 (0.5 - x), 2 (x - 0.5)]
CreateRandomNumber[] := Module[{r1, r2, done = True},
While[done,
r1 = RandomReal[];
r2 = RandomReal[];
If[r2 < Modifier[r1],
Return[r1];
done = False
]
]
]
numbers = Table[CreateRandomNumber[], 1000... | Give a code snippet in #Mathematica.2FWolfram_Language
Given a random number generator, (rng), generating numbers in the range 0.0 .. 1.0 called rgen, for example; and a function modifier(x)
taking an number in the same range and generating the probability that the input should be generated, in the same range 0..1; th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #SenseTalk | SenseTalk | ask "Enter the first number:"
put it into number1
ask "Enter the second number:"
put it into number2
put "Sum: " & number1 plus number2
put "Difference: " & number1 minus number2
put "Product: " & number1 multiplied by number2
put "Integer quotient: " & number1 div number2 -- Rounding towards 0
put "Remainder: " & ... | Give a code snippet in #SenseTalk
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #8th | 8th | "ha" 5 s:*
. cr | Give a code snippet in #8th
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) =>... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_format | Date format | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| #FutureBasic | FutureBasic | window 1
print date(@"yyyy-MM-dd")
print date(@"EEEE, MMMM dd, yyyy")
HandleEvents | Give a code snippet in #FutureBasic
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Logical_operations | Logical operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Rust | Rust |
fn boolean_ops(a: bool, b: bool) {
println!("{} and {} -> {}", a, b, a && b);
println!("{} or {} -> {}", a, b, a || b);
println!("{} xor {} -> {}", a, b, a ^ b);
println!("not {} -> {}\n", a, !a);
}
fn main() {
boolean_ops(true, true);
boolean_ops(true, false);
boolean_ops(false, true);
... | Give a code snippet in #Rust
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Command-line_arguments | Command-line arguments | Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| #Fortran | Fortran | program command_line_arguments
implicit none
integer, parameter :: len_max = 256
integer :: i , nargs
character (len_max) :: arg
nargs = command_argument_count()
!nargs = iargc()
do i = 0, nargs
call get_command_argument (i, arg)
!call getarg (i, arg)
write (*, '(a)') trim (arg)
end do
... | Give a code snippet in #Fortran
Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #Free_Pascal | Free Pascal | program queue;
{$IFDEF FPC}{$MODE DELPHI}{$IFDEF WINDOWS}{$APPTYPE CONSOLE}{$ENDIF}{$ENDIF}
{$ASSERTIONS ON}
uses Generics.Collections;
var
lQueue: TQueue<Integer>;
begin
lQueue := TQueue<Integer>.Create;
try
lQueue.EnQueue(1);
lQueue.EnQueue(2);
lQueue.EnQueue(3);
Write(lQueue.DeQueue:2); ... | Give a code snippet in #Free_Pascal
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #Objeck | Objeck |
class Caesar {
function : native : Encode(enc : String, offset : Int) ~ String {
offset := offset % 26 + 26;
encoded := "";
enc := enc->ToLower();
each(i : enc) {
c := enc->Get(i);
if(c->IsChar()) {
j := (c - 'a' + offset) % 26;
encoded->Append(j + 'a');
}
els... | Give a code snippet in #Objeck
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variable_declaration_reset | Variable declaration reset | A decidely non-challenging task to highlight a potential difference between programming languages.
Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ... | #jq | jq | [1,2,2,3,4,4,5]
| . as $array
| range(1;length)
| select( $array[.] == $array[.-1])
| Give a code snippet in #jq
A decidely non-challenging task to highlight a potential difference between programming languages.
Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Scope/Function_names_and_labels | Scope/Function names and labels | Task
Explain or demonstrate the levels of visibility of function names and labels within the language.
See also
Variables for levels of scope relating to visibility of program variables
Scope modifiers for general scope modification facilities
| #REXX | REXX | /*REXX program demonstrates the use of labels and also a CALL statement. */
blarney = -0 /*just a blarney & balderdash statement*/
signal do_add /*transfer program control to a label.*/
ttt = sinD(30) ... | Give a code snippet in #REXX
Task
Explain or demonstrate the levels of visibility of function names and labels within the language.
See also
Variables for levels of scope relating to visibility of program variables
Scope modifiers for general scope modification facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/XPath | XML/XPath | Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp Store #45x10^3">
<section name="heal... | #XProc | XProc | <p:pipeline xmlns:p="http://www.w3.org/ns/xproc"
name="one-two-three"
version="1.0">
<p:identity>
<p:input port="source">
<p:inline>
<root>
<first/>
<prices/>
<names/>
</root>
</p:inline>
</p:input>
</p:identity>
<p:insert match="/root/first" p... | Give a code snippet in #XProc
Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp Store #... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Price_fraction | Price fraction | A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to ... | #Action.21 | Action! | DEFINE COUNT="20"
BYTE ARRAY levels=[6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 91 96 101]
BYTE ARRAY values=[10 18 26 32 38 44 50 54 58 62 66 70 74 78 82 86 90 94 98 100]
PROC PrintValue(BYTE v)
PrintB(v/100) Put('.)
v=v MOD 100
PrintB(v/10)
v=v MOD 10
PrintB(v)
RETURN
BYTE FUNC Map(BYTE v)
BYTE... | Give a code snippet in #Action.21
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bulls_and_cows | Bulls and cows | Bulls and Cows
Task
Create a four digit random number from the digits 1 to 9, without duplication.
The program should:
ask for guesses to this number
reject guesses that are malformed
print the score for the guess
The score is computed as:
The player wins if the guess is the same as the random... | #AppleScript | AppleScript | on pickNumber()
set theNumber to ""
repeat 4 times
set theDigit to (random number from 1 to 9) as string
repeat while (offset of theDigit in theNumber) > 0
set theDigit to (random number from 1 to 9) as string
end repeat
set theNumber to theNumber & theDigit
end repeat
end pickNumber
to bulls of theGues... | Give a code snippet in #AppleScript
Bulls and Cows
Task
Create a four digit random number from the digits 1 to 9, without duplication.
The program should:
ask for guesses to this number
reject guesses that are malformed
print the score for the guess
The score is computed as:
The player wins i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Man_or_boy_test | Man or boy test | Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of the test was to distinguis... | #Ruby | Ruby | def a(k, x1, x2, x3, x4, x5)
b = lambda { k -= 1; a(k, b, x1, x2, x3, x4) }
k <= 0 ? x4[] + x5[] : b[]
end
puts a(10, lambda {1}, lambda {-1}, lambda {-1}, lambda {1}, lambda {0}) | Give a code snippet in #Ruby
Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stair-climbing_puzzle | Stair-climbing puzzle | From Chung-Chieh Shan (LtU):
Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function detects what happens and returns a... | #Racket | Racket | #lang racket
(define p 0.5001)
(define (step)
(> p (random)))
(define (step-up n)
(cond ((zero? n) 'done)
((step) (step-up (sub1 n)))
(else (step-up (add1 n)))))
(step-up 1) | Give a code snippet in #Racket
From Chung-Chieh Shan (LtU):
Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function de... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Consecutive_primes_with_ascending_or_descending_differences | Consecutive primes with ascending or descending differences | Task
Find and display here on this page, the longest sequence of consecutive prime numbers where the differences between the primes are strictly ascending.
Do the same for sequences of primes where the differences are strictly descending.
In both cases, show the sequence for primes < 1,000,000.
If there... | #FreeBASIC | FreeBASIC | #define UPPER 1000000
#include"isprime.bas"
dim as uinteger champ = 0, record = 0, streak, i, j, n
'first generate all the primes below UPPER
redim as uinteger prime(1 to 2)
prime(1) = 2 : prime(2) = 3
for i = 5 to UPPER step 2
if isprime(i) then
redim preserve prime(1 to ubound(prime) + 1)
prim... | Give a code snippet in #FreeBASIC
Task
Find and display here on this page, the longest sequence of consecutive prime numbers where the differences between the primes are strictly ascending.
Do the same for sequences of primes where the differences are strictly descending.
In both cases, show the sequence for ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" /... | #PicoLisp | PicoLisp | (load "@lib/xm.l")
(mapcar
'((L) (attr L 'Name))
(body (in "file.xml" (xml))) ) | Give a code snippet in #PicoLisp
Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gend... | christopher/rosetta-code | |
http://rosettacode.org/wiki/MD5 | MD5 | Task
Encode a string using an MD5 algorithm. The algorithm can be found on Wikipedia.
Optionally, validate your implementation by running all of the test values in IETF RFC (1321) for MD5.
Additionally, RFC 1321 provides more precise information on the algorithm than the Wikipedia article.
Warning:... | #Racket | Racket |
#lang racket
(require file/md5)
(md5 "")
(md5 "a")
(md5 "abc")
(md5 "message digest")
(md5 "abcdefghijklmnopqrstuvwxyz")
(md5 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")
(md5 "12345678901234567890123456789012345678901234567890123456789012345678901234567890")
| Give a code snippet in #Racket
Task
Encode a string using an MD5 algorithm. The algorithm can be found on Wikipedia.
Optionally, validate your implementation by running all of the test values in IETF RFC (1321) for MD5.
Additionally, RFC 1321 provides more precise information on the algorithm than the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep 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
... | #Perl | Perl | 1 while ($_ = shift and @ARGV and !fork);
sleep $_;
print "$_\n";
wait; | Give a code snippet in #Perl
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Prime_conspiracy | Prime conspiracy | A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of ... | #PicoLisp | PicoLisp |
(load "pluser/sieve.l") # See the task "Sieve of Eratosthanes"
(setq NthPrime '(
( 10 . 29)
( 100 . 541)
( 1000 . 7919)
( 10000 . 104729)
( 100000 . 1299709)
(1000000 . 15485863)))
(de conspiracy (Power)
(let (Upto (cdr (assoc (... | Give a code snippet in #PicoLisp
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided prefe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Median_filter | Median filter | The median filter takes in the neighbourhood the median color (see Median filter)
(to test the function below, you can use these input and output solutions)
| #Tcl | Tcl | package require Tk
# Set the color of a pixel
proc applyMedian {srcImage x y -> dstImage} {
set x0 [expr {$x==0 ? 0 : $x-1}]
set y0 [expr {$y==0 ? 0 : $y-1}]
set x1 $x
set y1 $y
set x2 [expr {$x+1==[image width $srcImage] ? $x : $x+1}]
set y2 [expr {$y+1==[image height $srcImage] ? $y : $y+1}... | Give a code snippet in #Tcl
The median filter takes in the neighbourhood the median color (see Median filter)
(to test the function below, you can use these input and output solutions)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Zebra_puzzle | Zebra puzzle | Zebra puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
The Zebra puzzle, a.k.a. Einstein's Riddle,
is a logic puzzle which is to be solved programmatically.
It has several variants, one of them this:
There are five houses.
The English man lives ... | #Perl | Perl | #!/usr/bin/perl
use utf8;
use strict;
binmode STDOUT, ":utf8";
my (@tgt, %names);
sub setprops {
my %h = @_;
my @p = keys %h;
for my $p (@p) {
my @v = @{ $h{$p} };
@tgt = map(+{idx=>$_-1, map{ ($_, undef) } @p}, 1 .. @v)
unless @tgt;
$names{$_} = $p for @v;
}
}
my $solve = sub {
for my $i (@tgt) {
... | Give a code snippet in #Perl
Zebra puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
The Zebra puzzle, a.k.a. Einstein's Riddle,
is a logic puzzle which is to be solved programmatically.
It has several variants, one of them this:
There are five hou... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stern-Brocot_sequence | Stern-Brocot sequence | For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member of the sequence and its prece... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.Linq;
static class Program {
static List<int> l = new List<int>() { 1, 1 };
static int gcd(int a, int b) {
return a > 0 ? a < b ? gcd(b % a, a) : gcd(a % b, b) : b; }
static void Main(string[] args) {
int max = 1000; int take... | Give a code snippet in #C.23
For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_float_arrays_to_a_text_file | Write float arrays to a text file | Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2, 3, 1e11};
y = {1, 1.41421356... | #Lua | Lua | filename = "file.txt"
x = { 1, 2, 3, 1e11 }
y = { 1, 1.4142135623730951, 1.7320508075688772, 316227.76601683791 };
xprecision = 3;
yprecision = 5;
fstr = "%."..tostring(xprecision).."f ".."%."..tostring(yprecision).."f\n"
fp = io.open( filename, "w+" )
for i = 1, #x do
fp:write( string.format( fstr, x[i], y... | Give a code snippet in #Lua
Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2, 3,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_smallest_number_with_exactly_n_divisors | Sequence: smallest number with exactly n divisors | Calculate the sequence where each term an is the smallest natural number that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: nth number with exactly... | #Ruby | Ruby | require 'prime'
def num_divisors(n)
n.prime_division.inject(1){|prod, (_p,n)| prod *= (n + 1) }
end
def first_with_num_divs(n)
(1..).detect{|i| num_divisors(i) == n }
end
p (1..15).map{|n| first_with_num_divs(n) }
| Give a code snippet in #Ruby
Calculate the sequence where each term an is the smallest natural number that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Seq... | 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... | #Nim | Nim | type Solution = tuple[p, s, f: int]
iterator solutions(max, total: Positive): Solution =
for p in countup(2, max, 2):
for s in 1..max:
if s == p: continue
let f = total - p - s
if f notin [p, s] and f in 1..max:
yield (p, s, f)
echo "P S F"
for sol in solutions(7, 12):
echo sol.p, ... | Give a code snippet in #Nim
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 (diff... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Topological_sort | Topological 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
... | #PicoLisp | PicoLisp | (de sortDependencies (Lst)
(setq Lst # Build a flat list
(uniq
(mapcan
'((L)
(put (car L) 'dep (cdr L)) # Store dependencies in 'dep' properties
(copy L) )
(mapcar uniq Lst) ) ) ) # without self-dependencies
(m... | Give a code snippet in #PicoLisp
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/Numbers_with_equal_rises_and_falls | Numbers with equal rises and falls | When a number is written in base 10, adjacent digits may "rise" or "fall" as the number is read (usually from left to right).
Definition
Given the decimal digits of the number are written as a series d:
A rise is an index i such that d(i) < d(i+1)
A fall is an index i such that ... | #MAD | MAD | NORMAL MODE IS INTEGER
VECTOR VALUES FMT = $I8,1H:,I9*$
INTERNAL FUNCTION(NUM)
ENTRY TO RISFAL.
N=NUM
DEPTH = 0
DIGA = N-(N/10)*10
N = N/10
LOOP WHENEVER N.E.0, FUNCTION RETURN DEPTH.E.0
DIGB = DIGA
... | Give a code snippet in #MAD
When a number is written in base 10, adjacent digits may "rise" or "fall" as the number is read (usually from left to right).
Definition
Given the decimal digits of the number are written as a series d:
A rise is an index i such that d(i) < d(i+1)
A fall i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Phix | Phix | atom t1 = time()+1
integer depth = 0
procedure recurse()
if time()>t1 then
?depth
t1 = time()+1
end if
depth += 1
-- only 1 of these will ever get called, of course...
recurse()
recurse()
recurse()
end procedure
recurse()
| Give a code snippet in #Phix
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Power_set | Power set | A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or pow... | #AWK | AWK | cat power_set.awk
#!/usr/local/bin/gawk -f
# User defined function
function tochar(l,n, r) {
while (l) { n--; if (l%2 != 0) r = r sprintf(" %c ",49+n); l = int(l/2) }; return r
}
# For each input
{ for (i=0;i<=2^NF-1;i++) if (i == 0) printf("empty\n"); else printf("(%s)\n",tochar(i,NF)) }
| Give a code snippet in #AWK
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Purity | Purity | data Iter = f => FoldNat <const $f One, $f>
data Ackermann = FoldNat <const Succ, Iter> | Give a code snippet in #Purity
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Logical_operations | Logical operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Nim | Nim | proc logic(a, b: bool) =
echo "a and b: ", a and b
echo "a or b: ", a or b
echo "not a: ", not a
echo "a xor b: ", a xor b | Give a code snippet in #Nim
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Accumulator_factory | Accumulator factory | A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed in so far to that accumulat... | #Ring | Ring | oGenerator = new Generator
Func main
oGenerator {
accumulator = generator(1)
see call accumulator(5)
see nl
generator(3)
see call accumulator(2.3)
}
Class Generator
aN = []
func generator i
aN + i
return eval(substr("return func d { ... | Give a code snippet in #Ring
A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values pass... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Almkvist-Giullera_formula_for_pi | Almkvist-Giullera formula for pi | The Almkvist-Giullera formula for calculating 1/π2 is based on the Calabi-Yau
differential equations of order 4 and 5, which were originally used to describe certain manifolds
in string theory.
The formula is:
1/π2 = (25/3) ∑0∞ ((6n)! / (n!6))(532n2 + 126n + 9) / 10002n+1
This formula can be used to calcul... | #J | J |
numerator =: monad define "0
(3 * (! x: y)^6) %~ 32 * (!6x*y) * (y*(126 + 532*y)) + 9x
)
term =: numerator % 10x ^ 3 + 6&*
echo 'The first 10 numerators are:'
echo ,. numerator i.10
echo ''
echo 'The sum of the first 10 terms (pi^-2) is ', 0j15 ": +/ term i.10
heron =: [: -: ] + %
sqrt =: dyad define NB... | Give a code snippet in #J
The Almkvist-Giullera formula for calculating 1/π2 is based on the Calabi-Yau
differential equations of order 4 and 5, which were originally used to describe certain manifolds
in string theory.
The formula is:
1/π2 = (25/3) ∑0∞ ((6n)! / (n!6))(532n2 + 126n + 9) / 10002n+1
This fo... | 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... | #ReScript | ReScript | let s1 = "hello"
let s2 = s1 ++ " literal"
Js.log(s1)
Js.log(s2)
| Give a code snippet in #ReScript
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abundant,_deficient_and_perfect_number_classifications | Abundant, deficient and perfect number classifications | These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as deficient (OEIS A005100).
if P(n)... | #ZX_Spectrum_Basic | ZX Spectrum Basic | 10 LET nd=1: LET np=0: LET na=0
20 FOR i=2 TO 20000
30 LET sum=1
40 LET max=i/2
50 LET n=2: LET l=max-1
60 IF n>l THEN GO TO 90
70 IF i/n=INT (i/n) THEN LET sum=sum+n: LET max=i/n: IF max<>n THEN LET sum=sum+max: LET l=max-1
80 LET n=n+1: GO TO 60
90 IF sum<i THEN LET nd=nd+1: GO TO 120
100 IF sum=i ... | Give a code snippet in #ZX_Spectrum_Basic
These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generator/Exponential | Generator/Exponential | A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that the internal state of the objec... | #Lingo | Lingo | squares = script("generator.power").new(2)
cubes = script("generator.power").new(3)
filter = script("generator.filter").new(squares, cubes)
filter.skip(20)
res = []
i = 0
repeat while filter.exec(res)
i = i + 1
if i>10 then exit repeat
put res[1]
end repeat | Give a code snippet in #Lingo
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Break | Loops/Break | Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If the number 10 is never gener... | #PHP | PHP | while (true) {
$a = rand(0,19);
echo "$a\n";
if ($a == 10)
break;
$b = rand(0,19);
echo "$b\n";
} | Give a code snippet in #PHP
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #ACL2 | ACL2 | (defun fast-fib-r (n a b)
(if (or (zp n) (zp (1- n)))
b
(fast-fib-r (1- n) b (+ a b))))
(defun fast-fib (n)
(fast-fib-r n 1 1))
(defun first-fibs-r (n i)
(declare (xargs :measure (nfix (- n i))))
(if (zp (- n i))
nil
(cons (fast-fib i)
(first-fibs-r n (1+ i)))))
... | Give a code snippet in #ACL2
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded c... | #jq | jq | # This filter may be applied to integers or integer-valued strings
def luhntest:
def digits: tostring | explode | map([.]|implode|tonumber);
(digits | reverse)
| ( [.[range(0;length;2)]] | add ) as $sum1
| [.[range(1;length;2)]]
| (map( (2 * .) | if . > 9 then (digits|add) else . end) | add) as $sum2
| ($s... | Give a code snippet in #jq
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct fo... | 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 ... | #Nial | Nial | multiply is operation a b {a * b} | Give a code snippet in #Nial
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_interpolation_(included) | String interpolation (included) |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Elixir | Elixir |
x = "little"
IO.puts "Mary had a #{x} lamb"
| Give a code snippet in #Elixir
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #PureBasic | PureBasic | #ToFind=8
#MaxTests=100
#True = 1: #False = 0
Declare is_happy(n)
If OpenConsole()
Define i=1,Happy
Repeat
If is_happy(i)
Happy+1
PrintN("#"+Str(Happy)+RSet(Str(i),3))
EndIf
i+1
Until Happy>=#ToFind
;
Print(#CRLF$+#CRLF$+"Press ENTER to exit"): Input()
CloseConsole()
EndIf
Proced... | Give a code snippet in #PureBasic
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 endles... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactl... | #Common_Lisp | Common Lisp | (defun trailing-zerop (number)
"Is the lowest digit of `number' a 0"
(zerop (rem number 10)))
(defun integer-digits (integer)
"Return the number of digits of the `integer'"
(assert (integerp integer))
(length (write-to-string integer)))
(defun paired-factors (number)
"Return a list of pairs that are fac... | Give a code snippet in #Common_Lisp
A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original numb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_simple | Abbreviations, simple | The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backup 2 bottom 1 Cappend 2 change 1 ... | #M2000_Interpreter | M2000 Interpreter |
Module Abbreviations_Simple {
Function Lex {
a$={add 1 alter 3 backup 2 bottom 1 Cappend 2 change 1 Schange Cinsert 2 Clast 3
compress 4 copy 2 count 3 Coverlay 3 cursor 3 delete 3 Cdelete 2 down 1 duplicate
3 xEdit 1 expand 3 extract 3 find 1 Nfind 2 Nfindup 6 NfUP 3 Cfind 2 findUP 3 fUP 2
... | Give a code snippet in #M2000_Interpreter
The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3... | christopher/rosetta-code | |
http://rosettacode.org/wiki/McNuggets_problem | McNuggets problem | Wikipedia
The McNuggets version of the coin problem was introduced by Henri Picciotto,
who included it in his algebra textbook co-authored with Anita Wah. Picciotto
thought of the application in the 1980s while dining with his son at
McDonald's, working the problem out on a napkin. A McNugget number is
the total number... | #11l | 11l | V nuggets = Set(0..100)
L(s, n, t) cart_product(0 .. 100 I/ 6,
0 .. 100 I/ 9,
0 .. 100 I/ 20)
nuggets.discard(6*s + 9*n + 20*t)
print(max(nuggets)) | Give a code snippet in #11l
Wikipedia
The McNuggets version of the coin problem was introduced by Henri Picciotto,
who included it in his algebra textbook co-authored with Anita Wah. Picciotto
thought of the application in the 1980s while dining with his son at
McDonald's, working the problem out on a napkin. A McNugg... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gray_code | Gray code | Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are many possible Gray codes. The follow... | #Pascal | Pascal | sub bin2gray
{
return $_[0] ^ ($_[0] >> 1);
}
sub gray2bin
{
my ($num)= @_;
my $bin= $num;
while( $num >>= 1 ) {
# a bit ends up flipped iff an odd number of bits to its left is set.
$bin ^= $num; # different from the suggested algorithm;
} # avoids using bit ma... | Give a code snippet in #Pascal
Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are many... | 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.
... | #Dao | Dao | for( i = 1 : 5 ){
for( j = 1 : i ) io.write( '*' )
io.writeln()
} | Give a code snippet in #Dao
“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 structure... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ramanujan_primes/twins | Ramanujan primes/twins | In a manner similar to twin primes, twin Ramanujan primes may be explored. The task is to determine how many of the first million Ramanujan primes are twins.
Related Task
Twin primes | #Nim | Nim | import math, sequtils, strutils, sugar, times
let t0 = now()
type PrimeCounter = seq[int32]
proc initPrimeCounter(limit: Positive): PrimeCounter {.noInit.} =
doAssert limit > 1
result = repeat(1i32, limit)
result[0] = 0
result[1] = 0
for i in countup(4, limit - 1, 2): result[i] = 0
var p = 3
var p2 ... | Give a code snippet in #Nim
In a manner similar to twin primes, twin Ramanujan primes may be explored. The task is to determine how many of the first million Ramanujan primes are twins.
Related Task
Twin primes | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #IDL | IDL | result = 1.0 + 0.5*randomn(seed,1000) | Give a code snippet in #IDL
Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nonogram_solver | Nonogram solver | A nonogram is a puzzle that provides
numeric clues used to fill in a grid of cells,
establishing for each cell whether it is filled or not.
The puzzle solution is typically a picture of some kind.
Each row and column of a rectangular grid is annotated with the lengths
of its distinct runs of occupied cells.
Using only... | #Julia | Julia | using Base.Iterators
struct NonogramPuzzle
nrows::Int
ncols::Int
xhints::Vector{Vector{Int}}
yhints::Vector{Vector{Int}}
solutions:: Vector{Any}
NonogramPuzzle(xh, yh) = new(length(xh), length(yh), xh, yh, Vector{NTuple{4,Array{Int64,1}}}())
end
ycols2xrows(ycols) = [[ycols[i][j] for i in ea... | Give a code snippet in #Julia
A nonogram is a puzzle that provides
numeric clues used to fill in a grid of cells,
establishing for each cell whether it is filled or not.
The puzzle solution is typically a picture of some kind.
Each row and column of a rectangular grid is annotated with the lengths
of its distinct run... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_square_curve | Sierpinski square curve |
Task
Produce a graphical or ASCII-art representation of a Sierpinski square curve of at least order 3.
| #Factor | Factor | USING: accessors kernel L-system sequences ui ;
: square-curve ( L-system -- L-system )
L-parser-dialect >>commands
[ 90 >>angle ] >>turtle-values
"F+XF+F+XF" >>axiom
{
{ "X" "XF-F+F-XF+F+XF-F+F-X" }
} >>rules ;
[
<L-system> square-curve
"Sierpinski square curve" open-window
] wi... | Give a code snippet in #Factor
Task
Produce a graphical or ASCII-art representation of a Sierpinski square curve of at least order 3.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Normal_distribution | Statistics/Normal distribution | The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform random number generator and create a ... | #C.2B.2B | C++ | #include <random>
#include <map>
#include <string>
#include <iostream>
#include <cmath>
#include <iomanip>
int main( ) {
std::random_device myseed ;
std::mt19937 engine ( myseed( ) ) ;
std::normal_distribution<> normDistri ( 2 , 3 ) ;
std::map<int , int> normalFreq ;
int sum = 0 ; //holds the sum of th... | Give a code snippet in #C.2B.2B
The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform rand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #COBOL | COBOL | >>SOURCE FORMAT FREE
*> This code is dedicated to the public domain
identification division.
program-id. dragon.
environment division.
configuration section.
repository. function all intrinsic.
data division.
working-storage section.
01 segment-length pic 9 value 2.
01 mark pic x value '.'.
01 segment-count... | Give a code snippet in #COBOL
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Floyd-Warshall_algorithm | Floyd-Warshall algorithm | The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already been checked for loops, parallel ... | #ObjectIcon | ObjectIcon | #
# Floyd-Warshall algorithm.
#
# See https://en.wikipedia.org/w/index.php?title=Floyd%E2%80%93Warshall_algorithm&oldid=1082310013
#
import io
import ipl.array
import ipl.printf
record fw_results (n, distance, next_vertex)
procedure main ()
local example_graph
local fw
local u, v
example_graph := [[1, -... | Give a code snippet in #ObjectIcon
The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has alrea... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Problem_of_Apollonius | Problem of Apollonius |
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the ... | #Sidef | Sidef | class Circle(x,y,r) {
method to_s { "Circle(#{x}, #{y}, #{r})" }
}
func solve_apollonius(c, s) {
var(c1, c2, c3) = c...;
var(s1, s2, s3) = s...;
var 𝑣11 = (2*c2.x - 2*c1.x);
var 𝑣12 = (2*c2.y - 2*c1.y);
var 𝑣13 = (c1.x**2 - c2.x**2 + c1.y**2 - c2.y**2 - c1.r**2 + c2.r**2);
var 𝑣14 ... | Give a code snippet in #Sidef
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightfo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm | Trabb Pardo–Knuth algorithm | The TPK algorithm is an early example of a programming chrestomathy.
It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages.
The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of... | #Icon_and_Unicon | Icon and Unicon | procedure main()
S := []
writes("Enter 11 numbers: ")
read() ? every !11 do (tab(many(' \t'))|0,put(S, tab(upto(' \t')|0)))
every item := !reverse(S) do
write(item, " -> ", (400 >= f(item)) | "overflows")
end
procedure f(x)
return abs(x)^0.5 + 5*x^3
end | Give a code snippet in #Icon_and_Unicon
The TPK algorithm is an early example of a programming chrestomathy.
It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages.
The report traces the early history of work in developing computer languages in the 1940s ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Nested | Loops/Nested | Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.
Specifically, this task als... | #MOO | MOO | a = make(10, make(10));
for i in [1..10]
for j in [1..10]
a[i][j] = random(20);
endfor
endfor
for i in [1..10]
s = "";
for j in [1..10]
s += tostr(" ", a[i][j]);
if (a[i][j] == 20)
break i;
endif
endfor
player:tell(s);
s = "";
endfor
player:tell(s); | Give a code snippet in #MOO
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Continued_fraction | Continued fraction | continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to write a program which generates su... | #PicoLisp | PicoLisp | (scl 49)
(de fsqrt2 (N A)
(default A 1)
(cond
((> A (inc N)) 2)
(T
(+
(if (=1 A) 1.0 2.0)
(*/ `(* 1.0 1.0) (fsqrt2 N (inc A))) ) ) ) )
(de pi (N A)
(default A 1)
(cond
((> A (inc N)) 6.0)
(T
(+
(if (=1 A) 3.0 6.0)
(*/
... | Give a code snippet in #PicoLisp
continued fraction
Mathworld
a
0
+
b
1
a
1
+
b
2
a
2
+
b
3
a
3
+
⋱
{\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}}
The task is to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/MAC_Vendor_Lookup | MAC Vendor Lookup | Every connected device around the world comes with a unique Media Access Control address, or a MAC address.
A common task a network administrator may come across is being able to identify a network device's manufacturer when given only a MAC address.
Task
Interface with one (or numerous) APIs that exist on the i... | #JavaScript | JavaScript |
var mac = "88:53:2E:67:07:BE";
function findmac(){
window.open("http://api.macvendors.com/" + mac);
}
findmac();
| Give a code snippet in #JavaScript
Every connected device around the world comes with a unique Media Access Control address, or a MAC address.
A common task a network administrator may come across is being able to identify a network device's manufacturer when given only a MAC address.
Task
Interface with one (o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bioinformatics/Sequence_mutation | Bioinformatics/Sequence mutation | Task
Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by:
Choosing a random base position in the sequence.
Mutate the sequence by doing one of either:
Swap the base at that position by changing it to one of A, C, G, or T. (which has a chance o... | #C.2B.2B | C++ | #include <array>
#include <iomanip>
#include <iostream>
#include <random>
#include <string>
class sequence_generator {
public:
sequence_generator();
std::string generate_sequence(size_t length);
void mutate_sequence(std::string&);
static void print_sequence(std::ostream&, const std::string&);
enum... | Give a code snippet in #C.2B.2B
Task
Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by:
Choosing a random base position in the sequence.
Mutate the sequence by doing one of either:
Swap the base at that position by changing it to one of A, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #Racket | Racket |
#lang racket
(file-or-directory-modify-seconds "foo.rkt")
| Give a code snippet in #Racket
Task
Get and set the modification time of a file.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Batch_File | Batch File | del input.txt
rd /s /q docs
del \input.txt
rd /s /q \docs | Give a code snippet in #Batch_File
Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_common_divisor | Greatest common divisor | Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest common measure.
Related tas... | #Pop11 | Pop11 | gcd_n(15, 12, 2) => | Give a code snippet in #Pop11
Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Object_serialization | Object serialization | Create a set of data types based upon inheritance. Each data type or class should have a print command that displays the contents of an instance of that class to standard output. Create instances of each class in your inheritance hierarchy and display them to standard output. Write each of the objects to a file named o... | #zkl | zkl | class [static] ARootClass{ // A top level class, no instances
class A{ self.println(" constructor"); } // a regular class
class B(A){ // ditto
var x;
fcn init(x=123){ self.x=x }
fcn toString{ "x is "+x }
}
}
ARootClass.B(456).println(); // create an instance
// prints:
Class(A) constr... | Give a code snippet in #zkl
Create a set of data types based upon inheritance. Each data type or class should have a print command that displays the contents of an instance of that class to standard output. Create instances of each class in your inheritance hierarchy and display them to standard output. Write each of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_using_a_custom_comparator | Sort using a custom comparator |
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.2B.2B | C++ | #include <algorithm>
#include <string>
#include <cctype>
// compare character case-insensitive
struct icompare_char {
bool operator()(char c1, char c2) {
return std::toupper(c1) < std::toupper(c2);
}
};
// return true if s1 comes before s2
struct compare {
bool operator()(std::string const& s1, std::strin... | Give a code snippet in #C.2B.2B
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/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Delphi | Delphi |
program createFile;
{$APPTYPE CONSOLE}
uses
Classes,
SysUtils;
const
filename = 'output.txt';
var
cwdPath,
fsPath: string;
// Create empty file in current working directory
function CreateEmptyFile1: Boolean;
var
f: textfile;
begin
// Make path to the file to be created
cwdPath := ExtractF... | Give a code snippet in #Delphi
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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.)
| #Arendelle | Arendelle |
/* ARM assembly Raspberry PI comment one line */
/* comment line 1
comment line 2
*/
mov r0,#0 @ this comment on end of line
mov r1,#0 // authorized comment
| Give a code snippet in #Arendelle
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/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/sub... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | RandNGen := function(n)
local v, rand;
v := [1 .. n - 1]*0;
Add(v, 1);
rand := function()
return Random(v);
end;
return rand;
end;
UnbiasedGen := function(rand)
local unbiased;
unbiased := function()
local a, b;
while true do
a := rand();
b := rand();
if a <> b then
break;
fi;
od;
re... | Give a code snippet in #F.C5.8Drmul.C3.A6
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random numbe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Globally_replace_text_in_several_files | Globally replace text in several files | Task
Replace every occurring instance of a piece of text in a group of text files with another one.
For this task we want to replace the text "Goodbye London!" with "Hello New York!" for a list of files.
| #Common_Lisp | Common Lisp |
(defun hello-goodbye (files)
(labels ((replace-from-file (file)
(with-open-file (in file)
(loop for line = (read-line in nil)
while line do
(loop for index = (search "Goodbye London!" line)
while index do
... | Give a code snippet in #Common_Lisp
Task
Replace every occurring instance of a piece of text in a group of text files with another one.
For this task we want to replace the text "Goodbye London!" with "Hello New York!" for a list of files.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_character_by_character/UTF8 | Read a file character by character/UTF8 | Task
Read a file one character at a time, as opposed to reading the entire file at once.
The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached).
The procedure should support the reading of files contain... | #PicoLisp | PicoLisp |
(in "wordlist"
(while (char)
(process @))
| Give a code snippet in #PicoLisp
Task
Read a file one character at a time, as opposed to reading the entire file at once.
The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached).
The procedure should su... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Password_generator | Password generator | Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-./:;<=>?@[]^_{|}~
(the above ch... | #Scala | Scala | object makepwd extends App {
def newPassword( salt:String = "", length:Int = 13, strong:Boolean = true ) = {
val saltHash = salt.hashCode & ~(1 << 31)
import java.util.Calendar._
val cal = java.util.Calendar.getInstance()
val rand = new scala.util.Random((cal.getTimeInMillis+saltHash).toLong)
... | Give a code snippet in #Scala
Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-./... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Action.21 | Action! | INCLUDE "D2:REAL.ACT" ;from the Action! Tool Kit
DEFINE R_="+0"
DEFINE I_="+6"
TYPE Complex=[CARD cr1,cr2,cr3,ci1,ci2,ci3]
BYTE FUNC Positive(REAL POINTER x)
BYTE ARRAY tmp
tmp=x
IF (tmp(0)&$80)=$00 THEN
RETURN (1)
FI
RETURN (0)
PROC PrintComplex(Complex POINTER x)
PrintR(x R_)
IF Positive(x I_)... | Give a code snippet in #Action.21
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
{\displ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conway%27s_Game_of_Life | Conway's Game of Life | The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, in an m-by-m (or m×m) sq... | #PL.2FI | PL/I | (subscriptrange):
Conway: procedure options (main); /* 20 November 2013 */
/* A grid of (1:100, 1:100) is desired; the array GRID is defined as (0:101, 0:101), */
/* to satisfy the requirement that elements off-grid are zero. */
declare n fixed binary; /* grid size) */
put ('W... | Give a code snippet in #PL.2FI
The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Walk_a_directory/Non-recursively | Walk a directory/Non-recursively | Task
Walk a given directory and print the names of files matching a given pattern.
(How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?)
Note: This task is for non-recursive methods. These tasks should read a single directory, not an entire directory tree.
... | #F.23 | F# | System.IO.Directory.GetFiles("c:\\temp", "*.xml")
|> Array.iter (printfn "%s") | Give a code snippet in #F.23
Task
Walk a given directory and print the names of files matching a given pattern.
(How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?)
Note: This task is for non-recursive methods. These tasks should read a single directory, n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/sub... | #PL.2FI | PL/I |
test: procedure options (main); /* 20 Nov. 2012 */
randN: procedure(N) returns (bit (1));
declare N fixed (1);
declare random builtin;
declare r fixed (2) external initial (-1);
if r >= 0 then do; r = r-1; return ('0'b); end;
r = random()*2*N;
return ('1'b);
end randN;
random: procedure returns ... | Give a code snippet in #PL.2FI
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Linear_congruential_generator | Linear congruential generator | The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_{0}}
is a seed.
r
1
... | #SequenceL | SequenceL |
import <Utilities/Random.sl>;
main(args(2)) :=
let
bsdRandomGenerator := newRandomGenerator(0, 0, 2147483647, bsdNext);
msRandomGenerator := newRandomGenerator(0, 0, 32767, msNext);
// Create a random sequence with each one of the generators
numbers := getRandomSequence([bsdRandomGenerator, msRandomGener... | Give a code snippet in #SequenceL
The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaysty... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #dc | dc | {} | Give a code snippet in #dc
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_an_object_method | Call an object method | In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static or class method, and an instance m... | #Objeck | Objeck |
ClassName->some_function(); # call class function
instance->some_method(); # call instance method | Give a code snippet in #Objeck
In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static or... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge 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
... | #Sidef | Sidef | func stooge(x, i, j) {
if (x[j] < x[i]) {
x.swap(i, j)
}
if (j-i > 1) {
var t = ((j - i + 1) / 3)
stooge(x, i, j - t)
stooge(x, i + t, j )
stooge(x, i, j - t)
}
}
var a = 10.of { 100.irand }
say "Before #{a}"
stooge(a, 0, a.end)
say "After #{a}" | Give a code snippet in #Sidef
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick so... | christopher/rosetta-code |
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