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/Count_in_factors | Count in factors | Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it would be shown as
2
×
3
{\di... | #Delphi | Delphi | function Factorize(n : Integer) : String;
begin
if n <= 1 then
Exit('1');
var k := 2;
while n >= k do begin
while (n mod k) = 0 do begin
Result += ' * '+IntToStr(k);
n := n div k;
end;
Inc(k);
end;
Result:=SubStr(Result, 4);
end;
var i : Integer;
for i := 1 to ... | Give a code snippet in #Delphi
Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it woul... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Sidef | Sidef | func double (n) { n << 1 }
func halve (n) { n >> 1 }
func isEven (n) { n&1 == 0 }
func ethiopian_mult(a, b) {
var r = 0
while (a > 0) {
r += b if !isEven(a)
a = halve(a)
b = double(b)
}
return r
}
say ethiopian_mult(17, 34) | Give a code snippet in #Sidef
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_inverse | Modular inverse | From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{\displaystyle \exists k\in \math... | #11l | 11l | F mul_inv(=a, =b)
V b0 = b
V x0 = 0
V x1 = 1
I b == 1 {R 1}
L a > 1
V q = a I/ b
(a, b) = (b, a % b)
(x0, x1) = (x1 - q * x0, x0)
I x1 < 0 {x1 += b0}
R x1
print(mul_inv(42, 2017)) | Give a code snippet in #11l
From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{\di... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hailstone_sequence | Hailstone sequence | The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1
The (unproven) Collatz conje... | #SNUSP | SNUSP | /@+@@@+++# 27
| halve odd /===count<<\ /recurse\ #/?\ zero
$>@/===!/===-?\==>?!/-<+++\ \!/=!\@\>?!\@/<@\.!\-/
/+<-\!>\?-<+>/++++<\?>+++/*6+4 | | \=/ \=itoa=@@@+@+++++#
\=>?/<=!=\ | | ! /+ !/+ !/+ !/+ \ mod10
|//!==/========\ | /<+> -\!?-\!?-... | Give a code snippet in #SNUSP
The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_pixel | Draw a pixel | Task
Create a window and draw a pixel in it, subject to the following:
the window is 320 x 240
the color of the pixel must be red (255,0,0)
the position of the pixel is x = 100, y = 100 | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program dpixel.s */
/* compile with as */
/* link with gcc and options -lX11 -L/usr/lpp/X11/lib */
/********************************************/
/*Constantes */
/********************************************/
.equ STDOUT, ... | Give a code snippet in #ARM_Assembly
Task
Create a window and draw a pixel in it, subject to the following:
the window is 320 x 240
the color of the pixel must be red (255,0,0)
the position of the pixel is x = 100, y = 100 | christopher/rosetta-code | |
http://rosettacode.org/wiki/Look-and-say_sequence | Look-and-say sequence | The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, 11, 21, 1211, 11122... | #Nim | Nim | iterator lookAndSay(n: int): string =
var current = "1"
yield current
for round in 2..n:
var ch = current[0]
var count = 1
var next = ""
for i in 1..current.high:
if current[i] == ch:
inc count
else:
next.add $count & ch
ch = current[i]
count = 1
cur... | Give a code snippet in #Nim
The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Old_lady_swallowed_a_fly | Old lady swallowed a fly | Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identical output.
Other tasks related to st... | #Commodore_BASIC | Commodore BASIC |
1 rem rosetta code
2 rem old lady who swallowed a fly
5 print chr$(147);chr$(14)
10 dim a$(10),ex$(10),mu$(8,3):a=1
15 for i=1 to 8:read a$(i),ex$(i):next i
20 for c=1 to 8
30 print chr$(147):print " Old Lady Who Swallowed A Fly ":print
40 print "I know an old lady who swallowed"
45 print " a ";a$(c):g... | Give a code snippet in #Commodore_BASIC
Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_case | String case | Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not reversable.
Show any additional... | #Delphi | Delphi | writeln(uppercase('alphaBETA'));
writeln(lowercase('alphaBETA')); | Give a code snippet in #Delphi
Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #Factor | Factor | : print-exists? ( path -- )
[ write ": " write ] [ exists? "exists." "doesn't exist." ? print ] bi ;
{ "input.txt" "/input.txt" "docs" "/docs" } [ print-exists? ] each | Give a code snippet in #Factor
Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works wi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_clock | Draw a clock | Task
Draw a clock.
More specific:
Draw a time keeping device. It can be a stopwatch, hourglass, sundial, a mouth counting "one thousand and one", anything. Only showing the seconds is required, e.g.: a watch with just a second hand will suffice. However, it must clearly change every second, and the change must cy... | #Locomotive_Basic | Locomotive Basic | 10 mode 1:defint a-y:deg
20 input "Current time (HH:MM)";t$
30 h=val(mid$(t$,1,2))
40 m=val(mid$(t$,4,2))
50 cls
60 r=150:s=-1
70 ph=0:pm=0
80 origin 320,200
90 for a=0 to 360 step 6
100 if a mod 30>0 then z=.9 else z=.8
110 move z*r*sin(a),z*r*cos(a)
120 draw r*sin(a),r*cos(a)
130 next
140 move 0,r
150 for a=0 to 360 ... | Give a code snippet in #Locomotive_Basic
Task
Draw a clock.
More specific:
Draw a time keeping device. It can be a stopwatch, hourglass, sundial, a mouth counting "one thousand and one", anything. Only showing the seconds is required, e.g.: a watch with just a second hand will suffice. However, it must clearly c... | 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... | #Python | Python | def stern_brocot(predicate=lambda series: len(series) < 20):
"""\
Generates members of the stern-brocot series, in order, returning them when the predicate becomes false
>>> print('The first 10 values:',
stern_brocot(lambda series: len(series) < 10)[:10])
The first 10 values: [1, 1, 2, 1... | Give a code snippet in #Python
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 memb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #min | min | (true) ("SPAM" puts!) while | Give a code snippet in #min
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers | Catalan numbers | Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
for
n
≥
0.
{\displaystyle C... | #Run_BASIC | Run BASIC | FOR i = 1 TO 15
PRINT i;" ";catalan(i)
NEXT
FUNCTION catalan(n)
catalan = 1
if n <> 0 then catalan = ((2 * ((2 * n) - 1)) / (n + 1)) * catalan(n - 1)
END FUNCTION | Give a code snippet in #Run_BASIC
Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe ... | #Pascal | Pascal | #!/usr/bin/perl
use strict;
use warnings;
my $nzero = -0.0;
my $nan = 0 + "nan";
my $pinf = +"inf";
my $ninf = -"inf";
printf "\$nzero = %.1f\n", $nzero;
print "\$nan = $nan\n";
print "\$pinf = $pinf\n";
print "\$ninf = $ninf\n\n";
printf "atan2(0, 0) = %g\n", atan2(0, 0);
printf "atan2(0, \$nzero) = %g\n", atan2... | Give a code snippet in #Pascal
The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #Raven | Raven | time dup print "\n" print int '%a %b %e %H:%M:%S %Y' date | Give a code snippet in #Raven
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Eertree | Eertree | An eertree is a data structure designed for efficient processing of certain palindrome tasks, for instance counting the number of sub-palindromes in an input string.
The data structure has commonalities to both tries and suffix trees.
See links below.
Task
Construct an eertree for the string "eertree", then outp... | #Go | Go | package main
import "fmt"
func main() {
tree := eertree([]byte("eertree"))
fmt.Println(subPalindromes(tree))
}
type edges map[byte]int
type node struct {
length int
edges
suffix int
}
const evenRoot = 0
const oddRoot = 1
func eertree(s []byte) []node {
tree := []node{
evenRoo... | Give a code snippet in #Go
An eertree is a data structure designed for efficient processing of certain palindrome tasks, for instance counting the number of sub-palindromes in an input string.
The data structure has commonalities to both tries and suffix trees.
See links below.
Task
Construct an eertree for the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #C.23 | C# | int[] values = new int[] {1,2,3,4,5,6,7,8,9,10};
int max = values.Max(); | Give a code snippet in #C.23
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, sho... | #Groovy | Groovy | def wordWrap(text, length = 80) {
def sb = new StringBuilder()
def line = ''
text.split(/\s/).each { word ->
if (line.size() + word.size() > length) {
sb.append(line.trim()).append('\n')
line = ''
}
line += " $word"
}
sb.append(line.trim()).toString(... | Give a code snippet in #Groovy
Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or pro... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #Common_Lisp | Common Lisp | (defun simple-moving-average (period &aux
(sum 0) (count 0) (values (make-list period)) (pointer values))
(setf (rest (last values)) values) ; construct circularity
(lambda (n)
(when (first pointer)
(decf sum (first pointer))) ; subtract old value
(incf sum n) ; add new v... | Give a code snippet in #Common_Lisp
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving avera... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitcoin/public_point_to_address | Bitcoin/public point to address | Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion.
The encoding steps are:
take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st... | #Wren | Wren | import "/crypto" for Sha256, Ripemd160
import "/str" for Str
import "/fmt" for Conv
// converts an hexadecimal string to a byte list.
var HexToBytes = Fn.new { |s| Str.chunks(s, 2).map { |c| Conv.atoi(c, 16) }.toList }
// Point is a class for a bitcoin public point
class Point {
construct new() {
_x = L... | Give a code snippet in #Wren
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion.
The encoding steps are:
take the X and Y coordinates of the given public point, and concatenate them in ord... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mind_boggling_card_trick | Mind boggling card trick | Mind boggling card trick
You are encouraged to solve this task according to the task description, using any language you may know.
Matt Parker of the "Stand Up Maths channel" has a YouTube video of a card trick that creates a semblance of order from chaos.
The task is to simulate the trick in a way that mimics th... | #Rust | Rust | extern crate rand; // 0.5.5
use rand::Rng;
use std::iter::repeat;
#[derive(Debug, Eq, PartialEq, Clone)]
enum Colour {
Black,
Red,
}
use Colour::*;
fn main() {
let mut rng = rand::thread_rng();
//Create our deck.
let mut deck: Vec<_> = repeat(Black).take(26)
.chain(repeat(Red).take(26)... | Give a code snippet in #Rust
Mind boggling card trick
You are encouraged to solve this task according to the task description, using any language you may know.
Matt Parker of the "Stand Up Maths channel" has a YouTube video of a card trick that creates a semblance of order from chaos.
The task is to simulate the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Subleq | Subleq | Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of signed integers. These integers... | #zkl | zkl | fcn subleq(a,a1,a2,etc){ a=vm.arglist.copy();
i:=0;
while(i>=0){ A,B,C:=a[i,3];
if(A==-1) a[B]=ask("::").toInt(); // or File.stdin.read(1)[0] // int
else if(B==-1) print(a[A].toChar());
else if( (a[B]-=a[A]) <=0) { i=C; continue; }
i+=3;
}
} | Give a code snippet in #zkl
Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of sign... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #Objective-C | Objective-C | NSDictionary *myDict = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt:13], @"hello",
[NSNumber numberWithInt:31], @"world",
[NSNumber numberWithInt:71], @"!", nil];
// iterating over keys:
for (id key in myDict) {
NSLog(@... | Give a code snippet in #Objective-C
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collection... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Tcl | Tcl | proc getNthLineFromFile {filename n} {
set f [open $filename]
while {[incr n -1] > 0} {
if {[gets $f line] < 0} {
close $f
error "no such line"
}
}
close $f
return $line
}
puts [getNthLineFromFile example.txt 7] | Give a code snippet in #Tcl
Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Narcissist | Narcissist | Quoting from the Esolangs wiki page:
A narcissist (or Narcissus program) is the decision-problem version of a quine.
A quine, when run, takes no input, but produces a copy of its own source code at its output. In contrast, a narcissist reads a string of symbols from its input, and produces no output except a "1" o... | #Python | Python |
import sys
with open(sys.argv[0]) as quine:
code = raw_input("Enter source code: ")
if code == quine.read():
print("Accept")
else:
print("Reject")
| Give a code snippet in #Python
Quoting from the Esolangs wiki page:
A narcissist (or Narcissus program) is the decision-problem version of a quine.
A quine, when run, takes no input, but produces a copy of its own source code at its output. In contrast, a narcissist reads a string of symbols from its input, and p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_primorial_primes | Sequence of primorial primes | The sequence of primorial primes is given as the increasing values of n where primorial(n) ± 1 is prime.
Noting that the n'th primorial is defined as the multiplication of the smallest n primes, the sequence is of the number of primes, in order that when multiplied together is one-off being a prime number itself.
T... | #Python | Python | import pyprimes
def primorial_prime(_pmax=500):
isprime = pyprimes.isprime
n, primo = 0, 1
for prime in pyprimes.nprimes(_pmax):
n, primo = n+1, primo * prime
if isprime(primo-1) or isprime(primo+1):
yield n
if __name__ == '__main__':
# Turn off warning on use of probabil... | Give a code snippet in #Python
The sequence of primorial primes is given as the increasing values of n where primorial(n) ± 1 is prime.
Noting that the n'th primorial is defined as the multiplication of the smallest n primes, the sequence is of the number of primes, in order that when multiplied together is one-off b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Interactive_programming_(repl) | Interactive programming (repl) | Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
Task
Show how to start this... | #Kotlin | Kotlin | c:\kotlin-compiler-1.0.6>kotlinc
Welcome to Kotlin version 1.0.6-release-127 (JRE 1.8.0_31-b13)
Type :help for help, :quit for quit
>>> fun f(s1: String, s2: String, sep: String) = s1 + sep + sep + s2
>>> f("Rosetta", "Code", ":")
Rosetta::Code
>>> :quit | Give a code snippet in #Kotlin
Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.... | 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 ... | #Tcl | Tcl | if {$foo == 3} {
puts "foo is three"
} elseif {$foo == 4} {
puts "foo is four"
} else {
puts "foo is neither three nor four"
} | Give a code snippet in #Tcl
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_whitespace_from_a_string/Top_and_tail | Strip whitespace from a string/Top and tail | Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace removed
For the purposes of thi... | #Ksh | Ksh |
#!/bin/ksh
# Strip whitespace from a string/Top and tail
# # Variables:
#
str=${1:-" This is a test. "}
# # Functions:
#
# # Function _striphead(str) - Return str with leading while space stripped
#
function _striphead {
typeset _str ; _str="$1"
echo "${_str##*(\s)}"
}
# # Function _striptail(str) -... | Give a code snippet in #Ksh
Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace remo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SEDOLs | SEDOLs | Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
... | #ALGOL_68 | ALGOL 68 | []INT sedol weights = (1, 3, 1, 7, 3, 9);
STRING reject = "AEIOUaeiou";
PROC strcspn = (STRING s,reject)INT: (
INT out:=0;
FOR i TO UPB s DO
IF char in string(s[i], LOC INT, reject) THEN
return out
FI;
out:=i
OD;
return out: out
);
PROC sedol checksum = (REF STRING sedol6)INT:
(
INT out;... | Give a code snippet in #ALGOL_68
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_numbers | Perfect numbers | Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself).
Note: The faster Luca... | #Swift | Swift | func perfect(n:Int) -> Bool {
var sum = 0
for i in 1..<n {
if n % i == 0 {
sum += i
}
}
return sum == n
}
for i in 1..<10000 {
if perfect(i) {
println(i)
}
} | Give a code snippet in #Swift
Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Truncatable_primes | Truncatable primes | A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number.
Examples
The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime.
The number 7393 is a right-truncatable prime as the numbers 7393, 7... | #Bracmat | Bracmat | ( 1000001:?i
& whl
' ( !i+-2:>0:?i
& !i:?L
& whl'(!L^1/2:#?^1/2&@(!L:% ?L))
& !L:~
)
& out$("left:" !i)
& 1000001:?i
& whl
' ( !i+-2:>0:?i
& !i:?R
& whl'(!R^1/2:#?^1/2&@(!R:?R %@))
& !R:~
)
& out$("right:" !i)
) | Give a code snippet in #Bracmat
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number.
Examples
The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime.
The number 7393 is a right-truncat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Haskell | Haskell | main = print $ "Incoming error--" ++ undefined
-- When run in GHC:
-- "Incoming error--*** Exception: Prelude.undefined | Give a code snippet in #Haskell
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Pangram_checker | Pangram checker | Pangram checker
You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.
For example: The quick brown fox jumps over the lazy dog.
Task
Write a function or method to chec... | #AWK | AWK | #!/usr/bin/awk -f
BEGIN {
allChars="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
print isPangram("The quick brown fox jumps over the lazy dog.");
print isPangram("The quick brown fo.");
}
function isPangram(string) {
delete X;
for (k=1; k<length(string); k++) {
X[toupper(substr(string,k,1))]++; # histogram
... | Give a code snippet in #AWK
Pangram checker
You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.
For example: The quick brown fox jumps over the lazy dog.
Task
Write... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compiler/code_generator | Compiler/code generator | A code generator translates the output of the syntax analyzer and/or semantic analyzer
into lower level code, either assembly, object, or virtual.
Task[edit]
Take the output of the Syntax analyzer task - which is a flattened Abstract Syntax Tree (AST) - and convert it to virtual machine code, that can be run by the
Vi... | #Phix | Phix | --
-- demo\rosetta\Compiler\cgen.e
-- ============================
--
-- The reusable part of cgen.exw
--
without js -- (machine code!)
include parse.e
global sequence vars = {},
strings = {},
stringptrs = {}
global integer chain = 0
global sequence code = {}
function var_idx(sequenc... | Give a code snippet in #Phix
A code generator translates the output of the syntax analyzer and/or semantic analyzer
into lower level code, either assembly, object, or virtual.
Task[edit]
Take the output of the Syntax analyzer task - which is a flattened Abstract Syntax Tree (AST) - and convert it to virtual machine c... | 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... | #Factor | Factor | : step-up ( -- ) step [ step-up step-up ] unless ; | Give a code snippet in #Factor
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/Averages/Median | Averages/Median | Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle values.
There are several approaches ... | #Action.21 | Action! | INCLUDE "H6:REALMATH.ACT"
DEFINE PTR="CARD"
PROC Sort(PTR ARRAY a INT count)
INT i,j,minpos
REAL POINTER tmp
FOR i=0 TO count-2
DO
minpos=i
FOR j=i+1 TO count-1
DO
IF RealGreaterOrEqual(a(minpos),a(j)) THEN
minpos=j
FI
OD
IF minpos#i THEN
tmp=a(i)
a(i)... | Give a code snippet in #Action.21
Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle val... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cheryl%27s_birthday | Cheryl's birthday | Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is.
Cheryl gave them a list of ten possible dates:
May 15, May 16, May 19
June 17, June 18
July 14, July 16
August 14, August 15, August 17
Cheryl then tells Albert the month of birth, ... | #Rust | Rust |
// This version is based on the Go version on Rosettacode
#[derive(PartialEq, Debug, Copy, Clone)]
enum Month {
May,
June,
July,
August,
}
#[derive(PartialEq, Debug, Copy, Clone)]
struct Birthday {
month: Month,
day: u8,
}
impl Birthday {
fn month_unique_in(&self, birthdays: &[Birthd... | Give a code snippet in #Rust
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is.
Cheryl gave them a list of ten possible dates:
May 15, May 16, May 19
June 17, June 18
July 14, July 16
August 14, August 15, August 17
Cheryl then tells A... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Runtime_evaluation | Runtime evaluation | Task
Demonstrate a language's ability for programs to execute code written in the language provided at runtime.
Show what kind of program fragments are permitted (e.g. expressions vs. statements), and how to get values in and out (e.g. environments, arguments, return values), if applicable what lexical/static environ... | #Nim | Nim | import ../compiler/[nimeval, llstream, ast], strformat, os
let std = findNimStdLibCompileTime()
let modules = [std, std / "pure", std / "std", std / "core"]
var intr = createInterpreter("script", modules)
#dynamic variable
let varname = commandLineParams()[0]
let expr = commandLineParams()[1]
#wrap the naked vari... | Give a code snippet in #Nim
Task
Demonstrate a language's ability for programs to execute code written in the language provided at runtime.
Show what kind of program fragments are permitted (e.g. expressions vs. statements), and how to get values in and out (e.g. environments, arguments, return values), if applicabl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inverted_index | Inverted index | An Inverted Index is a data structure used to create full text search.
Task
Given a set of text files, implement a program to create an inverted index.
Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms.
The search index can be i... | #C.2B.2B | C++ |
#include <algorithm>
#include <fstream>
#include <iostream>
#include <vector>
#include <string>
const std::string _CHARS = "abcdefghijklmnopqrstuvwxyz0123456789.:-_/";
const size_t MAX_NODES = 41;
class node
{
public:
node() { clear(); }
node( char z ) { clear(); }
~node() { for( int x = 0; x < MAX_NO... | Give a code snippet in #C.2B.2B
An Inverted Index is a data structure used to create full text search.
Task
Given a set of text files, implement a program to create an inverted index.
Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Java | Java | setrand(3)
random(6)+1
\\ chosen by fair dice roll.
\\ guaranteed to the random. | Give a code snippet in #Java
The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Rust | Rust | // [dependencies]
// svg = "0.8.0"
const SQRT3_2: f64 = 0.86602540378444;
fn sierpinski_triangle(
mut document: svg::Document,
mut x: f64,
mut y: f64,
mut side: f64,
order: usize,
) -> svg::Document {
use svg::node::element::Polygon;
if order == 1 {
let mut points = Vec::new();... | Give a code snippet in #Rust
Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Do-while | Loops/Do-while | Start with a value at 0. Loop while value mod 6 is not equal to 0.
Each time through the loop, add 1 to the value then print it.
The loop must execute at least once.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loo... | #Dragon | Dragon | val = 0
do{
val++
showln val
}while(val % 6 != 0) | Give a code snippet in #Dragon
Start with a value at 0. Loop while value mod 6 is not equal to 0.
Each time through the loop, add 1 to the value then print it.
The loop must execute at least once.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CRC-32 | CRC-32 |
Task
Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.
The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.
Algorithms are described on Computation of CRC in Wikipedia.
This variant of CRC-32 uses LSB-first order, sets the initial CRC to FFFFFFFF16, and... | #Elixir | Elixir | defmodule Test do
def crc32(str) do
IO.puts :erlang.crc32(str) |> Integer.to_string(16)
end
end
Test.crc32("The quick brown fox jumps over the lazy dog") | Give a code snippet in #Elixir
Task
Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.
The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.
Algorithms are described on Computation of CRC in Wikipedia.
This variant of CRC-32 uses LSB-first order, sets th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/DOM_serialization | XML/DOM serialization | Create a simple DOM and having it serialize to:
<?xml version="1.0" ?>
<root>
<element>
Some text here
</element>
</root>
| #D | D | module xmltest ;
import std.stdio ;
import std.xml ;
void main() {
auto doc = new Document("root") ;
//doc.prolog = q"/<?xml version="1.0"?>/" ; // default
doc ~= new Element("element", "Some text here") ;
writefln(doc) ;
// output: <?xml version="1.0"?><root><element>Some text here</element></root>
} | Give a code snippet in #D
Create a simple DOM and having it serialize to:
<?xml version="1.0" ?>
<root>
<element>
Some text here
</element>
</root>
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Carmichael_3_strong_pseudoprimes | Carmichael 3 strong pseudoprimes | A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it.
The Miller Rabin Test uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this.
The purpose of this task is to investigate such numbers using a met... | #Julia | Julia | using Primes
function carmichael(pmax::Integer)
if pmax ≤ 0 throw(DomainError("pmax must be strictly positive")) end
car = Vector{typeof(pmax)}(0)
for p in primes(pmax)
for h₃ in 2:(p-1)
m = (p - 1) * (h₃ + p)
pmh = mod(-p ^ 2, h₃)
for Δ in 1:(h₃+p-1)
... | Give a code snippet in #Julia
A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it.
The Miller Rabin Test uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this.
The purpose of this task is to inves... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cistercian_numerals | Cistercian numerals | Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999.
How they work
All Cistercian numerals begin with a vertical line segment, which by itself represents the number 0. Then, glyp... | #Java | Java | import java.util.Arrays;
import java.util.List;
public class Cistercian {
private static final int SIZE = 15;
private final char[][] canvas = new char[SIZE][SIZE];
public Cistercian(int n) {
initN();
draw(n);
}
public void initN() {
for (var row : canvas) {
... | Give a code snippet in #Java
Cistercian numerals were used across Europe by Cistercian monks during the Late Medieval Period as an alternative to Roman numerals. They were used to represent base 10 integers from 0 to 9999.
How they work
All Cistercian numerals begin with a vertical line segment, which by itself repre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Interactive_programming_(repl) | Interactive programming (repl) | Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
Task
Show how to start this... | #Forth | Forth | $ gforth
Gforth 0.7.0, Copyright (C) 1995-2008 Free Software Foundation, Inc.
Gforth comes with ABSOLUTELY NO WARRANTY; for details type `license'
Type `bye' to exit
ok
: f ( separator suffix prefix -- ) compiled
pad place 2swap 2dup compiled
pad +place compiled
pad +place compiled
pad +place c... | Give a code snippet in #Forth
Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #Golfscript | Golfscript | [296,{3/)}%-1%["No more"]+[" bottles":b]294*[b-1<]2*+[b]+[" of beer on the wall\n".8<"\nTake one down, pass it around\n"+1$n+]99*]zip | Give a code snippet in #Golfscript
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall... | 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... | #Argile | Argile | use std, array
let A = accumulator 42
print(A 0)
print(A 1)
print(A 10)
print(A 100)
let B = accumulator 4.2
print(B 0)
print(B 1)
print(B 10.0)
print(B 100.4)
~A ; ~B
(: use dbg; check mem leak :)
(: accumulator call :)
=: <accumulator a> <num x> := -> (a.t)
call ((a.func) as function(any)(a.t)->(a.t)) with... | Give a code snippet in #Argile
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 pa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #Visual_Basic_.NET | Visual Basic .NET | Dim s As String = "123"
s = CStr(CInt("123") + 1)
' or
s = (CInt("123") + 1).ToString | Give a code snippet in #Visual_Basic_.NET
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Semiprime | Semiprime | Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chosen as the length of the Arecib... | #zkl | zkl | fcn semiprime(n){
reg f = 0;
p:=2; while(f < 2 and p*p <= n){
while(0 == n % p){ n /= p; f+=1; }
p+=1;
}
return(f + (n > 1) == 2);
} | Give a code snippet in #zkl
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chose... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #PL.2FI | PL/I |
declare (L(30), R(30)) fixed binary;
declare (i, s) fixed binary;
L, R = 0;
put skip list
('Hello, please type two values and I will print their product:');
get list (L(1), R(1));
put edit ('The product of ', trim(L(1)), ' and ', trim(R(1)), ' is ') (a);
do i = 1 by 1 while (L(i) ^= 0);
... | Give a code snippet in #PL.2FI
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Van_der_Corput_sequence | Van der Corput sequence | When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
{\displaystyle 2^{1}}
; and so o... | #Action.21 | Action! | INCLUDE "D2:REAL.ACT" ;from the Action! Tool Kit
PROC Generate(INT value,base REAL POINTER res)
REAL denom,rbase,r1,r2
IntToReal(0,res)
IntToReal(1,denom)
IntToReal(base,rbase)
WHILE value#0
DO
RealMult(denom,rbase,r1)
RealAssign(r1,denom)
IntToReal(value MOD base,r1)
RealDiv(r1,denom,r2... | Give a code snippet in #Action.21
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort | Sorting algorithms/Gnome 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
... | #PowerShell | PowerShell |
function gnomesort($a) {
$size, $i, $j = $a.Count, 1, 2
while($i -lt $size) {
if ($a[$i-1] -le $a[$i]) {
$i = $j
$j++
}
else {
$a[$i-1], $a[$i] = $a[$i], $a[$i-1]
$i--
if($i -eq 0) {
$i = $j
... | Give a code snippet in #PowerShell
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 |
Qui... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stirling_numbers_of_the_second_kind | Stirling numbers of the second kind | Stirling numbers of the second kind, or Stirling partition numbers, are the
number of ways to partition a set of n objects into k non-empty subsets. They are
closely related to Bell numbers, and may be derived from them.
Stirling numbers of the second kind obey the recurrence relation:
S2(n, 0) and S2(0, k) = 0 ... | #Ruby | Ruby | @memo = {}
def sterling2(n, k)
key = [n,k]
return @memo[key] if @memo.key?(key)
return 1 if n.zero? and k.zero?
return 0 if n.zero? or k.zero?
return 1 if n == k
return 0 if k > n
res = k * sterling2(n-1, k) + sterling2(n - 1, k-1)
@memo[key] = res
end
r = (0..12)
puts "Sterling2 numbers:"
puts "n/... | Give a code snippet in #Ruby
Stirling numbers of the second kind, or Stirling partition numbers, are the
number of ways to partition a set of n objects into k non-empty subsets. They are
closely related to Bell numbers, and may be derived from them.
Stirling numbers of the second kind obey the recurrence relation:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Add_a_variable_to_a_class_instance_at_runtime | Add a variable to a class instance at runtime | Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at An Exercise in Metaprogramming with Ruby. This is re... | #ActionScript | ActionScript | var object:Object = new Object();
object.foo = "bar"; | Give a code snippet in #ActionScript
Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at An Exercise in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bead_sort | Sorting algorithms/Bead sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | beadsort[ a ] := Module[ { m, sorted, s ,t },
sorted = a; m = Max[a]; t=ConstantArray[0, {m,m} ];
If[ Min[a] < 0, Print["can't sort"]];
For[ i = 1, i < Length[a], i++, t[[i,1;;a[[i]]]]=1 ]
For[ i = 1 ,i <= m, i++, s = Total[t[[;;,i]]];
t[[ ;; , i]] = 0; t[[1 ;; s , i]] = 1; ]
For[ i=1,i<=Length[a],i++, sorted[[i]] ... | Give a code snippet in #Mathematica.2FWolfram_Language
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 |... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Test_a_function | Test a function |
Task
Using a well-known testing-specific library/module/suite for your language, write some tests for your language's entry in Palindrome.
If your language does not have a testing specific library well known to the language's community then state this or omit the language.
| #C.2B.2B | C++ | #include <algorithm>
#include <string>
constexpr bool is_palindrome(std::string_view s)
{
return std::equal(s.begin(), s.begin()+s.length()/2, s.rbegin());
}
| Give a code snippet in #C.2B.2B
Task
Using a well-known testing-specific library/module/suite for your language, write some tests for your language's entry in Palindrome.
If your language does not have a testing specific library well known to the language's community then state this or omit the language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/RSA_code | RSA code | Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryption is that you can distribute the... | #C | C |
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <gmp.h>
int main(void)
{
mpz_t n, d, e, pt, ct;
mpz_init(pt);
mpz_init(ct);
mpz_init_set_str(n, "9516311845790656153499716760847001433441357", 10);
mpz_init_set_str(e, "65537", 10);
mpz_init_set_str(d, "5617843187844953170... | Give a code snippet in #C
Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryption is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Colorful_numbers | Colorful numbers | A colorful number is a non-negative base 10 integer where the product of every sub group of consecutive digits is unique.
E.G.
24753 is a colorful number. 2, 4, 7, 5, 3, (2×4)8, (4×7)28, (7×5)35, (5×3)15, (2×4×7)56, (4×7×5)140, (7×5×3)105, (2×4×7×5)280, (4×7×5×3)420, (2×4×7×5×3)840
Every product is unique.
2346 ... | #Raku | Raku | sub is-colorful (Int $n) {
return True if 0 <= $n <= 9;
return False if $n.contains(0) || $n.contains(1) || $n < 0;
my @digits = $n.comb;
my %sums = @digits.Bag;
return False if %sums.values.max > 1;
for 2..@digits -> $group {
@digits.rotor($group => 1 - $group).map: { %sums{ [×] $_ }++ ... | Give a code snippet in #Raku
A colorful number is a non-negative base 10 integer where the product of every sub group of consecutive digits is unique.
E.G.
24753 is a colorful number. 2, 4, 7, 5, 3, (2×4)8, (4×7)28, (7×5)35, (5×3)15, (2×4×7)56, (4×7×5)140, (7×5×3)105, (2×4×7×5)280, (4×7×5×3)420, (2×4×7×5×3)840
Eve... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hailstone_sequence | Hailstone sequence | The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1
The (unproven) Collatz conje... | #COBOL | COBOL | identification division.
program-id. hailstones.
remarks. cobc -x hailstones.cob.
data division.
working-storage section.
01 most constant as 1000000.
01 coverage constant as 100000.
01 stones usage binary-long.
... | Give a code snippet in #COBOL
The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #APL | APL | toRoman←{
⍝ Digits and corresponding values
ds←((⊢≠⊃)⊆⊢)' M CM D CD C XC L XL X IX V IV I'
vs←1000, ,100 10 1∘.×9 5 4 1
⍝ Input ≤ 0 is invalid
⍵≤0:⎕SIGNAL 11
{ 0=d←⊃⍸vs≤⍵:⍬ ⍝ Find highest digit in number
(d⊃ds),∇⍵-d⊃vs ⍝ While one exists, add it and subtract from number
}⍵
} | Give a code snippet in #APL
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
k_ = Rexx
bigDigits = 999999999 -- Maximum setting for digits allowed by NetRexx
numeric digits bigDigits
loop k_ = 1
say k_
end k_
| Give a code snippet in #NetRexx
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Video_display_modes | Video display modes | The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| #6502_Assembly | 6502 Assembly | LDA #3
JSR $FE95 | Give a code snippet in #6502_Assembly
The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/ABC_problem | ABC problem | ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet is guaranteed amongst all sid... | #PowerShell | PowerShell | <#
.Synopsis
ABC Problem
.DESCRIPTION
You are given a collection of ABC blocks. Just like the ones you had when you were a kid.
There are twenty blocks with two letters on each block. You are guaranteed to have a
complete alphabet amongst all sides of the blocks
blocks = "BO","XK","DQ","CP","NA","GT","R... | Give a code snippet in #PowerShell
ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Time_a_function | Time a function | Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
between start and finish, which could ... | #Raven | Raven | define doId use $x
$x dup * $x /
define doPower use $v, $p
$v $p pow
define doSort
group
20000 each choose
list sort reverse
define timeFunc use $fName
time as $t1
$fName "" prefer call
time as $t2
$fName $t2 $t1 -"%.4g secs for %s\n" print
"NULL" timeFunc
42 "doId" timeFunc
12 2 "... | Give a code snippet in #Raven
Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
between... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/With_multiple_ranges | Loops/With multiple ranges | Loops/With multiple ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages allow multiple loop ranges, such as the PL/I example (snippet) below.
/* all variables are DECLARED as integers. */
prod=... | #Red | Red | Red ["For loop with multiple ranges"]
->: make op! function [start end][
res: copy []
repeat n 1 + absolute to-integer end - start [
append res start + either start > end [1 - n][n - 1]
]
]
by: make op! function [s w] [extract s absolute w]
for: function ['word ranges body][
inp: copy []
... | Give a code snippet in #Red
Loops/With multiple ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages allow multiple loop ranges, such as the PL/I example (snippet) below.
/* all variables are DECLARED as... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Shoelace_formula_for_polygonal_area | Shoelace formula for polygonal area | Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns the absolute value)
Task
Write ... | #TI-83_BASIC | TI-83 BASIC | [[3,4][5,11][12,8][9,5][5,6]]->[A]
Dim([A])->N:0->A
For(I,1,N)
I+1->J:If J>N:Then:1->J:End
A+[A](I,1)*[A](J,2)-[A](J,1)*[A](I,2)->A
End
Abs(A)/2->A | Give a code snippet in #TI-83_BASIC
Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs retu... | 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.
| #FreeBASIC | FreeBASIC | ' version 16-09-2015
' compile with: fbc -s console
' OR compile with: fbc -s gui
' Ported from the C version
Sub Br_line(x0 As Integer, y0 As Integer, x1 As Integer, y1 As Integer, Col As Integer = &HFFFFFF)
Dim As Integer dx = Abs(x1 - x0), dy = Abs(y1 - y0)
Dim As Integer sx = IIf(x0 < x1, 1, -1)
Dim... | Give a code snippet in #FreeBASIC
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/24_game/Solve | 24 game/Solve | task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| #Euler_Math_Toolbox | Euler Math Toolbox |
>function try24 (v) ...
$n=cols(v);
$if n==1 and v[1]~=24 then
$ "Solved the problem",
$ return 1;
$endif
$loop 1 to n
$ w=tail(v,2);
$ loop 1 to n-1
$ h=w; a=v[1]; b=w[1];
$ w[1]=a+b; if try24(w); ""+a+"+"+b+"="+(a+b), return 1; endif;
$ w[1]=a-b; if try24(w); ""+a+"-"+b+"="+(a-b), return 1; endif;
$ ... | Give a code snippet in #Euler_Math_Toolbox
task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_an_integer_array | Sort an integer array |
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
... | #WDTE | WDTE | let a => import 'arrays';
a.sort [39; 47; 40; 53; 14; 23; 88; 52; 78; 62; 41; 92; 88; 66; 5; 40] < -- io.writeln io.stdout; | Give a code snippet in #WDTE
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/Color_quantization | Color quantization | full color
Example: Gimp 16 color
Color quantization is the process of reducing number of colors used in an image while trying to maintain the visual appearance of the original image. In general, it is a form of cluster analysis, if each RGB color value is considered as a coordinate triple in the 3D colorspace. There... | #Common_Lisp | Common Lisp | (defpackage #:quantize
(:use #:cl
#:opticl))
(in-package #:quantize)
(defun image->pixels (image)
(check-type image 8-bit-rgb-image)
(let (pixels)
(do-pixels (y x) image
(push (pixel* image y x) pixels))
pixels))
(defun greatest-color-range (pixels)
(loop for (r g b) in pixels
... | Give a code snippet in #Common_Lisp
full color
Example: Gimp 16 color
Color quantization is the process of reducing number of colors used in an image while trying to maintain the visual appearance of the original image. In general, it is a form of cluster analysis, if each RGB color value is considered as a coordina... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Frink | Frink | test = "🐱abcdefg😾"
n = 3
m = 2
println[substrLen[test, n, m]]
println[right[test, -m]]
println[left[test, -1]]
pos = indexOf["c"]
if pos != -1
println[substrLen[test, pos, m]]
pos = indexOf[test, "cd"]
if pos != -1
println[substrLen[test, pos, m]]
| Give a code snippet in #Frink
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/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #MiniScript | MiniScript | keys = ["foo", "bar", "val"]
values = ["little", "miss", "muffet"]
d = {}
for i in range(keys.len-1)
d[keys[i]] = values[i]
end for
print d | Give a code snippet in #MiniScript
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Temperature_conversion | Temperature conversion | There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 kelvin.
0 kelvin is absolute z... | #zkl | zkl | K:=ask(0,"Kelvin: ").toFloat();
println("K %.2f".fmt(K));
println("F %.2f".fmt(K*1.8 - 459.67));
println("C %.2f".fmt(K - 273.15));
println("R %.2f".fmt(K*1.8)); | Give a code snippet in #zkl
There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 ke... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ordered_words | Ordered words | An ordered word is a word in which the letters appear in alphabetic order.
Examples include abbey and dirt.
Task[edit]
Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length.
(Examples that access the dictionary file locally assume that you have download... | #Sidef | Sidef | var words = [[]]
var file = %f'unixdict.txt'
file.open_r(\var fh, \var err) ->
|| die "Can't open file #{file}: $#{err}"
fh.each { |line|
line.trim!
if (line == line.sort) {
words[line.length] := [] << line
}
}
say words[-1].join(' ') | Give a code snippet in #Sidef
An ordered word is a word in which the letters appear in alphabetic order.
Examples include abbey and dirt.
Task[edit]
Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length.
(Examples that access the dictionary file locall... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic_evaluation | Arithmetic evaluation | Create a program which parses and evaluates arithmetic expressions.
Requirements
An abstract-syntax tree (AST) for the expression must be created from parsing the input.
The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.)
The ... | #ZX_Spectrum_Basic | ZX Spectrum Basic | 10 PRINT "Use integer numbers and signs"'"+ - * / ( )"''
20 LET s$="": REM last symbol
30 LET pc=0: REM parenthesis counter
40 LET i$="1+2*(3+(4*5+6*7*8)-9)/10"
50 PRINT "Input = ";i$
60 FOR n=1 TO LEN i$
70 LET c$=i$(n)
80 IF c$>="0" AND c$<="9" THEN GO SUB 170: GO TO 130
90 IF c$="+" OR c$="-" THEN GO SUB 200: GO TO ... | Give a code snippet in #ZX_Spectrum_Basic
Create a program which parses and evaluates arithmetic expressions.
Requirements
An abstract-syntax tree (AST) for the expression must be created from parsing the input.
The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Minesweeper_game | Minesweeper game | There is an n by m grid that has a random number (between 10% to 20% of the total number of tiles, though older implementations may use 20%..60% instead) of randomly placed mines that need to be found.
Positions in the grid are modified by entering their coordinates where the first coordinate is horizontal in the grid... | #Ceylon | Ceylon | import ceylon.random {
DefaultRandom
}
class Cell() {
shared variable Boolean covered = true;
shared variable Boolean flagged = false;
shared variable Boolean mined = false;
shared variable Integer adjacentMines = 0;
string =>
if (covered && !flagged)
then "."
else if (covered && flagged)
... | Give a code snippet in #Ceylon
There is an n by m grid that has a random number (between 10% to 20% of the total number of tiles, though older implementations may use 20%..60% instead) of randomly placed mines that need to be found.
Positions in the grid are modified by entering their coordinates where the first coor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Kaprekar_numbers | Kaprekar numbers | A positive integer is a Kaprekar number if:
It is 1 (unity)
The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number.
Note that a split resulting in a part consisting purely of 0s is not valid,
as 0 is not considered positive.
... | #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
func Kaprekar(N, B); \Returns 'true' if N is a Kaprekar number in base B
int N, B;
real N2, D; int Q, R;
[N2:= sq(float(N)); \N squared
D:= float(B); \(divider)
loop [Q:= fix(N2/D - Mod(N2,1.)); \get left pa... | Give a code snippet in #XPL0
A positive integer is a Kaprekar number if:
It is 1 (unity)
The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number.
Note that a split resulting in a part consisting purely of 0s is not valid,
as ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/AKS_test_for_primes | AKS test for primes | The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the coefficients of the polynomial ... | #CoffeeScript | CoffeeScript | pascal = () ->
a = []
return () ->
if a.length is 0 then a = [1]
else
b = (a[i] + a[i+1] for i in [0 ... a.length - 1])
a = [1].concat(b).concat [1]
show = (a) ->
show_x = (e) ->
switch e
when 0 then ""
when 1 then "x"
els... | Give a code snippet in #CoffeeScript
The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knight%27s_tour | Knight's tour |
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; that is, the knight need not e... | #Perl | Perl | use strict;
use warnings;
# Find a knight's tour
my @board;
# Choose starting position - may be passed in on command line; if
# not, choose random square.
my ($i, $j);
if (my $sq = shift @ARGV) {
die "$0: illegal start square '$sq'\n" unless ($i, $j) = from_algebraic($sq);
} else {
($i, $j) = (int rand 8, int ... | Give a code snippet in #Perl
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Rank_languages_by_popularity | Rosetta Code/Rank languages by popularity | Rosetta Code/Rank languages by popularity
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Sort the most popular computer programming languages based in number of members in Rosetta Code categories.
Sample output on 01 juin 2022 at 14:13 +02
Rank: 1 (1,... | #Haskell | Haskell | {-# LANGUAGE OverloadedStrings #-}
import Data.Aeson
import Network.HTTP.Base (urlEncode)
import Network.HTTP.Conduit (simpleHttp)
import Data.List (sortBy, groupBy)
import Data.Function (on)
import Data.Map (Map, toList)
-- Record representing a single language.
data Language =
Language {
name ... | Give a code snippet in #Haskell
Rosetta Code/Rank languages by popularity
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Sort the most popular computer programming languages based in number of members in Rosetta Code categories.
Sample output on 01 jui... | 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"
| #LFE | LFE |
$ ./bin/lfe -pa ebin/ -c "alpha beta" -h "gamma"
| Give a code snippet in #LFE
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/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... | #UnixPipes | UnixPipes | (echo 1024>p.res;tail -f p.res) | while read a ; do
test $a -gt 0 && (expr $a / 2 >> p.res ; echo $a) || exit 0
done | Give a code snippet in #UnixPipes
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/Dow... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cramer%27s_rule | Cramer's rule | linear algebra
Cramer's rule
system of linear equations
Given
{
a
1
x
+
b
1
y
+
c
1
z
=
d
1
a
2
x
+
b
2
y
+
c
2
z
=
d
2
a
3
x
+
b
3
y
+
c
3
z
=
d
3
{\displaystyle \left\{{\begin{matrix}a_{1}x+b_{1}y+c_{1}z&={\color {red}d_{1... | #Groovy | Groovy | class CramersRule {
static void main(String[] args) {
Matrix mat = new Matrix(Arrays.asList(2d, -1d, 5d, 1d),
Arrays.asList(3d, 2d, 2d, -6d),
Arrays.asList(1d, 3d, 3d, -1d),
Arrays.asList(5d, -2d, -3d, 3d))
List<Double> b = Arrays.asList(-3d, -32d, -47... | Give a code snippet in #Groovy
linear algebra
Cramer's rule
system of linear equations
Given
{
a
1
x
+
b
1
y
+
c
1
z
=
d
1
a
2
x
+
b
2
y
+
c
2
z
=
d
2
a
3
x
+
b
3
y
+
c
3
z
=
d
3
{\displaystyle \left\{{\begin{matrix}a_{1}x+... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #AppleScript | AppleScript | reverseString("Hello World!")
on reverseString(str)
reverse of characters of str as string
end reverseString | Give a code snippet in #AppleScript
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
... | 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.
| #Delphi | Delphi | program Project2;
{$APPTYPE CONSOLE}
uses
SysUtils;
function Recursive(Level : Integer) : Integer;
begin
try
Level := Level + 1;
Result := Recursive(Level);
except
on E: EStackOverflow do
Result := Level;
end;
end;
begin
Writeln('Recursion Level is ', Recursive(0));
Writeln('Press any ... | Give a code snippet in #Delphi
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/Polynomial_long_division | Polynomial long division |
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In algebra, polynomial long division is an algorithm for d... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <assert.h>
#include <gsl/gsl_vector.h>
#define MAX(A,B) (((A)>(B))?(A):(B))
void reoshift(gsl_vector *v, int h)
{
if ( h > 0 ) {
gsl_vector *temp = gsl_vector_alloc(v->size);
gsl_vector_view p = gsl_vector_subvector(v, 0, v->size - h);
... | Give a code snippet in #C
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In algebra, polynomial long div... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brilliant_numbers | Brilliant numbers | Brilliant numbers are a subset of semiprime numbers. Specifically, they are numbers that are the product of exactly two prime numbers that both have the same number of digits when expressed in base 10.
Brilliant numbers are useful in cryptography and when testing prime factoring algorithms.
E.G.
3 × 3 (9) is a bri... | #Perl | Perl | use strict;
use warnings;
use feature 'say';
use List::AllUtils <max head firstidx uniqint>;
use ntheory <primes is_semiprime forsetproduct>;
sub table { my $t = shift() * (my $c = 1 + length max @_); ( sprintf( ('%'.$c.'d')x@_, @_) ) =~ s/.{1,$t}\K/\n/gr }
sub comma { reverse ((reverse shift) =~ s/(.{3})/$1,/gr) =~ ... | Give a code snippet in #Perl
Brilliant numbers are a subset of semiprime numbers. Specifically, they are numbers that are the product of exactly two prime numbers that both have the same number of digits when expressed in base 10.
Brilliant numbers are useful in cryptography and when testing prime factoring algorithm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Picat | Picat | go =>
S = "Picat is fun",
N = 3,
M = 4,
C = 'i', % must be a char
SS = "is",
test(S,N,M,C,SS).
test(S,N,M,C,SS) =>
println($test(S,N,M,C,SS)),
% - starting from n characters in and of m length;
println(1=slice(S,N,N+M)),
println(1=S[N..N+M]),
% - starting from n characters in, up to the en... | Give a code snippet in #Picat
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/Factors_of_an_integer | Factors of an 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 |... | #Red | Red | Red []
factors: function [n [integer!]] [
n: absolute n
collect [
repeat i (sq: sqrt n) - 1 [
if n % i = 0 [
keep i
keep n / i
]
]
if sq = sq: to-integer sq [keep sq]
]
]
foreach num [
24
-64 ; negative
64 ... | Give a code snippet in #Red
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/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #Elena | Elena | public program()
{
while (true)
{
console.writeLine:"spam"
}
} | Give a code snippet in #Elena
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loop... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pseudo-random_numbers/Splitmix64 | Pseudo-random numbers/Splitmix64 | Splitmix64 is the default pseudo-random number generator algorithm in Java and is included / available in many other languages. It uses a fairly simple algorithm that, though it is considered to be poor for cryptographic purposes, is very fast to calculate, and is "good enough" for many random number needs. It passes s... | #Perl | Perl | use strict;
use warnings;
no warnings 'portable';
use feature 'say';
use Math::AnyNum qw(:overload);
package splitmix64 {
sub new {
my ($class, %opt) = @_;
bless {state => $opt{seed}}, $class;
}
sub next_int {
my ($self) = @_;
my $next = $self->{state} = ($self->{state}... | Give a code snippet in #Perl
Splitmix64 is the default pseudo-random number generator algorithm in Java and is included / available in many other languages. It uses a fairly simple algorithm that, though it is considered to be poor for cryptographic purposes, is very fast to calculate, and is "good enough" for many ra... | 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... | #REALbasic | REALbasic | Function Repeat(s As String, count As Integer) As String
Dim output As String
For i As Integer = 0 To count
output = output + s
Next
Return output
End Function
| Give a code snippet in #REALbasic
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*",... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Flow-control_structures | Flow-control structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
Document common flow-control structures.
One common example of a flow-control structure is the goto construct.
Note that Conditional Struc... | #zkl | zkl | continue; continue(n); // continue nth nested loop
break; break(n); // break out of nth nested loop
try{ ... }catch(exception){ ... } [else{ ... }]
onExit(fcn); // run fcn when enclosing function exits | Give a code snippet in #zkl
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
Document common flow-control structures.
One common example of a flow-control structure is the goto construct.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Quackery | Quackery | say " ________ ___ ___ ________ ________ ___ __ _______ ________ ___ ___" cr
say "|\ __ \|\ \|\ \|\ __ \|\ ____\|\ \|\ \ |\ ___ \ |\ __ \|\ \ / /|" cr
say "\ \ \|\ \ \ \ \ \ \ \|\ \ \ \___|\ \ \/ /|\ \ __/|\ \ \|\ \ \ \/ / /" cr
say " \ \ \ \ \ \ \ \ \ \ __ \ \ \... | Give a code snippet in #Quackery
Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Gauss-Jordan_matrix_inversion | Gauss-Jordan matrix inversion | Task
Invert matrix A using Gauss-Jordan method.
A being an n × n matrix.
| #Fortran | Fortran | !-----------------------------------------------------------------------
! gjinv - Invert a matrix, Gauss-Jordan algorithm
! A is destroyed.
!
!___Name_______Type_______________In/Out____Description_________________
! A(LDA,N) Real In An N by N matrix
! LDA Integer In ... | Give a code snippet in #Fortran
Task
Invert matrix A using Gauss-Jordan method.
A being an n × n matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/I_before_E_except_after_C | I before E except after C | The phrase "I before E, except after C" is a
widely known mnemonic which is supposed to help when spelling English words.
Task
Using the word list from http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
check if the two sub-clauses of the phrase are plausible individually:
"I before E when not pre... | #Erlang | Erlang |
-module(cei).
-export([plaus/0,count/3]).
plaus() ->
{ok,Words} = file:read_file("unixdict.txt"),
... | Give a code snippet in #Erlang
The phrase "I before E, except after C" is a
widely known mnemonic which is supposed to help when spelling English words.
Task
Using the word list from http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
check if the two sub-clauses of the phrase are plausible individual... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_entire_file | Write entire file | Task
(Over)write a file so that it contains a string.
The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.
| #Java | Java | import java.io.*;
public class Test {
public static void main(String[] args) throws IOException {
try (BufferedWriter bw = new BufferedWriter(new FileWriter("test.txt"))) {
bw.write("abc");
}
}
} | Give a code snippet in #Java
Task
(Over)write a file so that it contains a string.
The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.
| christopher/rosetta-code |
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