task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
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|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Call_a_function_in_a_shared_library | Call a function in a shared library | Show how to call a function in a shared library (without dynamically linking to it at compile-time). In particular, show how to call the shared library function if the library is available, otherwise use an internal equivalent function.
This is a special case of calling a foreign language function where the focus is c... | #Tcl | Tcl | package require Ffidl
if {[catch {
ffidl::callout OpenImage {pointer-utf8} int [ffidl::symbol fakeimglib.so openimage]
}]} then {
# Create the OpenImage command by other means here...
}
set handle [OpenImage "/the/file/name"] | Give a code snippet in #Tcl
Show how to call a function in a shared library (without dynamically linking to it at compile-time). In particular, show how to call the shared library function if the library is available, otherwise use an internal equivalent function.
This is a special case of calling a foreign language ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #BASIC256 | BASIC256 | source = freefile
open (source, "m:\text.txt")
textEnt$ = ""
dim textSal$(size(source)*8)
linea = 0
while not eof(source)
textEnt$ = readline(source)
linea += 1
textSal$[linea] = textEnt$
end while
for n = size(source) to 1 step -1
print textSal$[n];
next n
close source | Give a code snippet in #BASIC256
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Apply_a_callback_to_an_array | Apply a callback to an array | Task
Take a combined set of elements and apply a function to each element.
| #Ursala | Ursala | #import nat
#cast %nL
demo = successor* <325,32,67,1,3,7,315> | Give a code snippet in #Ursala
Task
Take a combined set of elements and apply a function to each element.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Additive_primes | Additive primes | Definitions
In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes.
Task
Write a program to determine (and show here) all additive primes less than 500.
Optionally, show the number of additive primes.
Also see
the OEIS entry: A046704 additive primes.
... | #BASIC256 | BASIC256 | print "Prime", "Digit Sum"
for i = 2 to 499
if isprime(i) then
s = digSum(i)
if isPrime(s) then print i, s
end if
next i
end
function isPrime(v)
if v < 2 then return False
if v mod 2 = 0 then return v = 2
if v mod 3 = 0 then return v = 3
d = 5
while d * d <= v
if v ... | Give a code snippet in #BASIC256
Definitions
In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes.
Task
Write a program to determine (and show here) all additive primes less than 500.
Optionally, show the number of additive primes.
Also see
the OEIS ent... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Ringing_the_terminal_bell | Terminal control/Ringing the terminal bell |
Task
Make the terminal running the program ring its "bell".
On modern terminal emulators, this may be done by playing some other sound which might or might not be configurable, or by flashing the title bar or inverting the colors of the screen, but was classically a physical bell within the terminal. It is usua... | #Applescript | Applescript | beep | Give a code snippet in #Applescript
Task
Make the terminal running the program ring its "bell".
On modern terminal emulators, this may be done by playing some other sound which might or might not be configurable, or by flashing the title bar or inverting the colors of the screen, but was classically a physical b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/JSON | JSON | Load a JSON string into a data structure.
Also, create a new data structure and serialize it into JSON.
Use objects and arrays (as appropriate for your language)
and make sure your JSON is valid (https://jsonformatter.org).
| #PicoLisp | PicoLisp | (de checkJson (X Item)
(unless (= X Item)
(quit "Bad JSON" Item) ) )
(de readJson ()
(case (read "_")
("{"
(make
(for (X (readJson) (not (= "}" X)) (readJson))
(checkJson ":" (readJson))
(link (cons X (readJson)))
(T (= "}" (setq X ... | Give a code snippet in #PicoLisp
Load a JSON string into a data structure.
Also, create a new data structure and serialize it into JSON.
Use objects and arrays (as appropriate for your language)
and make sure your JSON is valid (https://jsonformatter.org).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Monty_Hall_problem | Monty Hall problem |
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for the time being.
The game show hos... | #Liberty_BASIC | Liberty BASIC |
'adapted from BASIC solution
DIM doors(3) '0 is a goat, 1 is a car
total = 10000 'set desired number of iterations
switchWins = 0
stayWins = 0
FOR plays = 1 TO total
winner = INT(RND(1) * 3) + 1
doors(winner) = 1'put a winner in a random door
choice = INT(RND(1) * 3) + 1'pick a door, any door
DO... | Give a code snippet in #Liberty_BASIC
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catamorphism | Catamorphism | Reduce is a function or method that is used to take the values in an array or a list and apply a function to successive members of the list to produce (or reduce them to), a single value.
Task
Show how reduce (or foldl or foldr etc), work (or would be implemented) in your language.
See also
Wikipedia article: ... | #Scala | Scala | object Main extends App {
val a = Seq(1, 2, 3, 4, 5)
println(s"Array : ${a.mkString(", ")}")
println(s"Sum : ${a.sum}")
println(s"Difference : ${a.reduce { (x, y) => x - y }}")
println(s"Product : ${a.product}")
println(s"Minimum : ${a.min}")
println(s"Maximum : ${a.max}")
} | Give a code snippet in #Scala
Reduce is a function or method that is used to take the values in an array or a list and apply a function to successive members of the list to produce (or reduce them to), a single value.
Task
Show how reduce (or foldl or foldr etc), work (or would be implemented) in your language.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #Delphi | Delphi | program Stack;
{$APPTYPE CONSOLE}
uses Generics.Collections;
var
lStack: TStack<Integer>;
begin
lStack := TStack<Integer>.Create;
try
lStack.Push(1);
lStack.Push(2);
lStack.Push(3);
Assert(lStack.Peek = 3); // 3 should be at the top of the stack
Writeln(lStack.Pop); // 3
Writeln(lS... | Give a code snippet in #Delphi
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is a... | 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... | #Objective-C | Objective-C | #import <Foundation/Foundation.h>
int main(int argc, const char * argv[])
{
@autoreleasepool {
if(argc > 1)
{
NSString *arg1 = [NSString stringWithCString:argv[1] encoding:NSUTF8StringEncoding];
// encoding shouldn't matter in this case
double kelvin = [arg1 do... | Give a code snippet in #Objective-C
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 2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #Retro | Retro | { #1 #2 #3 } { #4 #5 #6 } a:append | Give a code snippet in #Retro
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Largest_proper_divisor_of_n | Largest proper divisor of n | Task
a(1) = 1; for n > 1, a(n) = largest proper divisor of n, where n < 101 .
| #BASIC256 | BASIC256 | print "El mayor divisor propio de n es:\n"
print " 1 1 ";
for i = 3 to 100
for j = i-1 to 1 step -1
If i % j = 0 then
print " "; j; " ";
exit for
end if
next j
if i % 10 = 0 then print
next i
end | Give a code snippet in #BASIC256
Task
a(1) = 1; for n > 1, a(n) = largest proper divisor of n, where n < 101 .
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Almost_prime | Almost prime | A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, where
k
=
2
{\displaystyl... | #XBasic | XBasic |
' Almost prime
PROGRAM "almostprime"
VERSION "0.0002"
DECLARE FUNCTION Entry()
INTERNAL FUNCTION KPrime(n%%, k%%)
FUNCTION Entry()
FOR k@@ = 1 TO 5
PRINT "k ="; k@@; ":";
i%% = 2
c%% = 0
DO WHILE c%% < 10
IFT KPrime(i%%, k@@) THEN
PRINT FORMAT$(" ###", i%%);
INC c%%
E... | Give a code snippet in #XBasic
A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Logical_operations | Logical operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #PostScript | PostScript |
/logical{
/a exch def
/b exch def
a b and =
a b or =
a not =
}def
| Give a code snippet in #PostScript
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Racket | Racket |
#lang racket
;; fast
(define (string-repeat n str)
(string-append* (make-list n str)))
(string-repeat 5 "ha") ; => "hahahahaha"
| Give a code snippet in #Racket
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function... | #FutureBasic | FutureBasic | void local fn Function1( count as long, ... )
va_list ap
long value
va_start( ap, count )
while ( count )
value = fn va_argLong( ap )
printf @"%ld",value
count--
wend
va_end( ap )
end fn
void local fn Function2( obj as CFTypeRef, ... )
va_list ap
va_start( ap, obj )
while ( obj )
... | Give a code snippet in #FutureBasic
Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #Rust | Rust |
use std::fs;
fn main() {
let err = "File move error";
fs::rename("input.txt", "output.txt").ok().expect(err);
fs::rename("docs", "mydocs").ok().expect(err);
fs::rename("/input.txt", "/output.txt").ok().expect(err);
fs::rename("/docs", "/mydocs").ok().expect(err);
}
| Give a code snippet in #Rust
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, base... | #Bracmat | Bracmat | whl
' ( arg$:?command
& ( get'db
| (db=1)&lst$(db,db,NEW)
)
& !command
: ( add
& :?name:?tag:?date
& whl
' ( arg$:?argmnt
& arg$:?value
& (!argmnt.!value)
: ( (title|name.?name)
| (category|tag.?tag)
... | Give a code snippet in #Bracmat
Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could ... | 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
| #F.23 | F# | open System
let rec gcd x y = if x = y || x = 0 then y else if x < y then gcd y x else gcd y (x-y)
let abs (x : int) = Math.Abs x
let sign (x: int) = Math.Sign x
let cint s = Int32.Parse(s)
type Rat(x : int, y : int) =
let g = if y = 0 then 0 else gcd (abs x) (abs y)
member this.n = if g = 0 then sign y * s... | Give a code snippet in #F.23
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/Copy_stdin_to_stdout | Copy stdin to stdout | Create an executable file that copies stdin to stdout, or else a script that does so through the invocation of an interpreter at the command line.
| #Lua | Lua | lua -e 'for x in io.lines() do print(x) end' | Give a code snippet in #Lua
Create an executable file that copies stdin to stdout, or else a script that does so through the invocation of an interpreter at the command line.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division | Sequence of primes by trial division | Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by... | #Kotlin | Kotlin | // version 1.0.6
fun isPrime(n: Int): Boolean {
if (n < 2) return false
if (n % 2 == 0) return n == 2
if (n % 3 == 0) return n == 3
var d : Int = 5
while (d * d <= n) {
if (n % d == 0) return false
d += 2
if (n % d == 0) return false
d += 4
}
return true
}
... | Give a code snippet in #Kotlin
Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #BQN | BQN | Rot ← ¬⊸{-⌾(𝕨⊸⊑)⌽𝕩}
Turns ← {{𝕩∾1∾¬⌾((⌊2÷˜≠)⊸⊑)𝕩}⍟𝕩 ⥊1}
•Plot´ <˘⍉>+` (<0‿1)(Rot˜)`Turns 3 | Give a code snippet in #BQN
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included) | Arbitrary-precision integers (included) | Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | #Sather | Sather | class MAIN is
main is
r:INTI;
p1 ::= "62060698786608744707";
p2 ::= "92256259918212890625";
-- computing 5^(4^(3^2)), it could be written
-- also e.g. (5.inti)^((4.inti)^((3.inti)^(2.inti)))
r := (3.pow(2)).inti;
r := (4.inti).pow(r);
r := (5.inti).pow(r);
sr ::= r.str; -- s... | Give a code snippet in #Sather
Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Smarandache_prime-digital_sequence | Smarandache prime-digital sequence | The Smarandache prime-digital sequence (SPDS for brevity) is the sequence of primes whose digits are themselves prime.
For example 257 is an element of this sequence because it is prime itself and its digits: 2, 5 and 7 are also prime.
Task
Show the first 25 SPDS primes.
Show the hundredth SPDS prime.
See also
... | #Lua | Lua | -- FUNCS:
local function T(t) return setmetatable(t, {__index=table}) end
table.firstn = function(t,n) local s=T{} n=n>#t and #t or n for i = 1,n do s[i]=t[i] end return s end
-- SIEVE:
local sieve, S = {}, 50000
for i = 2,S do sieve[i]=true end
for i = 2,S do if sieve[i] then for j=i*i,S,i do sieve[j]=nil end end en... | Give a code snippet in #Lua
The Smarandache prime-digital sequence (SPDS for brevity) is the sequence of primes whose digits are themselves prime.
For example 257 is an element of this sequence because it is prime itself and its digits: 2, 5 and 7 are also prime.
Task
Show the first 25 SPDS primes.
Show the hundre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_to_100 | Sum to 100 | Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular sum (in this iconic case, ... | #Raku | Raku | my $sum = 100;
my $N = 10;
my @ops = ['-', ''], |( [' + ', ' - ', ''] xx 8 );
my @str = [X~] map { .Slip }, ( @ops Z 1..9 );
my %sol = @str.classify: *.subst( ' - ', ' -', :g )\
.subst( ' + ', ' ', :g ).words.sum;
my %count.push: %sol.map({ .value.elems => .key });
my $max-solutions ... | Give a code snippet in #Raku
Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring/Top_and_tail | Substring/Top and tail | The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
If the program uses UTF-8 or UTF... | #Erlang | Erlang | 1> Str = "Hello".
"Hello"
2> string:sub_string(Str, 2). % To strip the string from the right by 1
"ello"
3> string:sub_string(Str, 1, length(Str)-1). % To strip the string from the left by 1
"Hell"
4> string:sub_string(Str, 2, length(Str)-1). % To strip the string from both sides by 1
"ell" | Give a code snippet in #Erlang
The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Formatted_numeric_output | Formatted numeric output | Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| #Maple | Maple | printf("%f", Pi);
3.141593
printf("%.0f", Pi);
3
printf("%.2f", Pi);
3.14
printf("%08.2f", Pi);
00003.14
printf("%8.2f", Pi);
3.14
printf("%-8.2f|", Pi);
3.14 |
printf("%+08.2f", Pi);
+0003.14
printf("%+0*.*f",8, 2, Pi);
+0003.14 | Give a code snippet in #Maple
Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Chinese_remainder_theorem | Chinese remainder theorem | Suppose
n
1
{\displaystyle n_{1}}
,
n
2
{\displaystyle n_{2}}
,
…
{\displaystyle \ldots }
,
n
k
{\displaystyle n_{k}}
are positive integers that are pairwise co-prime.
Then, for any given sequence of integers
a
1
{\displaystyle a_{1}}
,
a
2
... | #Ruby | Ruby |
def chinese_remainder(mods, remainders)
max = mods.inject( :* )
series = remainders.zip( mods ).map{|r,m| r.step( max, m ).to_a }
series.inject( :& ).first #returns nil when empty
end
p chinese_remainder([3,5,7], [2,3,2]) #=> 23
p chinese_remainder([10,4,9], [11,22,19]) #=> ni... | Give a code snippet in #Ruby
Suppose
n
1
{\displaystyle n_{1}}
,
n
2
{\displaystyle n_{2}}
,
…
{\displaystyle \ldots }
,
n
k
{\displaystyle n_{k}}
are positive integers that are pairwise co-prime.
Then, for any given sequence of integers
a
1
{\displayst... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Home_primes | Home primes |
This page uses content from Wikipedia. The original article was at Home prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In number theory, the home prime HP(n) of an integer n greater than 1 is... | #Perl | Perl | use strict;
use warnings;
use ntheory 'factor';
for my $m (2..20, 65) {
my (@steps, @factors) = $m;
push @steps, join '_', @factors while (@factors = factor $steps[-1] =~ s/_//gr) > 1;
my $step = $#steps;
if ($step >= 1) { print 'HP' . $_ . "($step) = " and --$step or last for @steps }
else ... | Give a code snippet in #Perl
This page uses content from Wikipedia. The original article was at Home prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In number theory, the home prime HP(n) of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Gambas | Gambas | Public Sub Form_Open()
Dim sChar As String
sChar = InputBox("Enter a character")
Print "Character " & sChar & " = ASCII " & Str(Asc(sChar))
sChar = InputBox("Enter a ASCII code")
Print "ASCII code " & sChar & " represents " & Chr(Val(sChar))
End | Give a code snippet in #Gambas
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Scala | Scala | object IntCompare {
def main(args: Array[String]): Unit = {
val a=Console.readInt
val b=Console.readInt
if (a < b)
printf("%d is less than %d\n", a, b)
if (a == b)
printf("%d is equal to %d\n", a, b)
if (a > b)
printf("%d is greater than %d\n", a, b)
}
} | Give a code snippet in #Scala
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/Cantor_set | Cantor set | Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| #Sidef | Sidef | func cantor (height) {
var width = 3**(height - 1)
var lines = height.of { "\N{FULL BLOCK}" * width }
func trim_middle_third (len, start, index) {
var seg = (len // 3) || return()
for i, j in ((index ..^ height) ~X (0 ..^ seg)) {
lines[i].replace!(Regex("^.{#{start + seg + j}... | Give a code snippet in #Sidef
Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Null_object | Null object |
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your language by checking to see if an ob... | #ALGOL_W | ALGOL W | begin
% declare a record type - will be accessed via references %
record R( integer f1, f2, f3 );
% declare a reference to a R instance %
reference(R) refR;
% assign null to the reference %
refR := null;
... | Give a code snippet in #ALGOL_W
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your lan... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #IDL | IDL | $ls | Give a code snippet in #IDL
Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_HTML_table | Create an HTML table | Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers.
The... | #Pascal | Pascal | <@ SDCLIT>
<@ DTBLIT>
<@ DTRLITLIT>
<@ DTDLITLIT>|[style]background-color:white</@>
<@ DTD>X</@>
<@ DTD>Y</@>
<@ DTD>Z</@>|[style]width:100%; background-color:brown;color:white; text-align:center</@>
<@ ITEFORLIT>10|
<@ DTRLITCAP>
<@ DTDPOSFORLIT>...|[style]background-color:Brown; color:white; te... | Give a code snippet in #Pascal
Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled wi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evaluate_binomial_coefficients | Evaluate binomial coefficients | This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
)
…
(
n
−
k
+
1
)
k
(
k
−
1... | #Elixir | Elixir | defmodule RC do
def choose(n,k) when is_integer(n) and is_integer(k) and n>=0 and k>=0 and n>=k do
if k==0, do: 1, else: choose(n,k,1,1)
end
def choose(n,k,k,acc), do: div(acc * (n-k+1), k)
def choose(n,k,i,acc), do: choose(n, k, i+1, div(acc * (n-i+1), i))
end
IO.inspect RC.choose(5,3)
IO.inspect RC.ch... | Give a code snippet in #Elixir
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #C.2B.2B | C++ | #include <direct.h>
#include <fstream>
int main() {
std::fstream f("output.txt", std::ios::out);
f.close();
f.open("/output.txt", std::ios::out);
f.close();
_mkdir("docs");
_mkdir("/docs");
return 0;
} | Give a code snippet in #C.2B.2B
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stirling_numbers_of_the_first_kind | Stirling numbers of the first kind | Stirling numbers of the first kind, or Stirling cycle numbers, count permutations according to their number
of cycles (counting fixed points as cycles of length one).
They may be defined directly to be the number of permutations of n
elements with k disjoint cycles.
Stirling numbers of the first kind express coeffici... | #J | J | NB. agenda set by the test according to the definition
test=: 1 i.~ (0 0&-: , 1 0&-:)@:*@:, , <
s1=: 1:`0:`0:`($:&<: + (($: * [)~ <:)~)@.test
s1&> table i. 13
+----+------------------------------------------------------------------------------------------+
|s1&>|0 1 2 3 4 ... | Give a code snippet in #J
Stirling numbers of the first kind, or Stirling cycle numbers, count permutations according to their number
of cycles (counting fixed points as cycles of length one).
They may be defined directly to be the number of permutations of n
elements with k disjoint cycles.
Stirling numbers of the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_the_coins | Count the coins | There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels and 5 pennies
A nickel and 10 pen... | #JavaScript | JavaScript | function countcoins(t, o) {
'use strict';
var targetsLength = t + 1;
var operandsLength = o.length;
t = [1];
for (var a = 0; a < operandsLength; a++) {
for (var b = 1; b < targetsLength; b++) {
// initialise undefined target
t[b] = t[b] ? t[b] : 0;
/... | Give a code snippet in #JavaScript
There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels ... | 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... | #Pascal | Pascal | label
jumpto;
begin
...
jumpto:
some statement;
...
goto jumpto;
...
end; | Give a code snippet in #Pascal
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/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #Kotlin | Kotlin | // version 1.0.6
fun log2(d: Double) = Math.log(d) / Math.log(2.0)
fun shannon(s: String): Double {
val counters = mutableMapOf<Char, Int>()
for (c in s) {
if (counters.containsKey(c)) counters[c] = counters[c]!! + 1
else counters.put(c, 1)
}
val nn = s.length.toDouble()
var sum... | Give a code snippet in #Kotlin
Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary),... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap | Bitmap | Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB color,
one to set a given pixe... | #Phix | Phix | with javascript_semantics
-- Some colour constants:
constant black = #000000,
-- blue = #0000FF,
-- green = #00FF00,
-- red = #FF0000,
white = #FFFFFF
-- Create new image filled with some colour
function new_image(integer width, integer height, integer fill_colour=black)
return repea... | Give a code snippet in #Phix
Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB col... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Metered_concurrency | Metered concurrency | The goal of this task is to create a counting semaphore used to control the execution of a set of concurrent units. This task intends to demonstrate coordination of active concurrent units through the use of a passive concurrent unit. The operations for a counting semaphore are acquire, release, and count. Each active ... | #Icon_and_Unicon | Icon and Unicon | procedure main(A)
n := integer(A[1] | 3) # Max. number of active tasks
m := integer(A[2] | 2) # Number of visits by each task
k := integer(A[3] | 5) # Number of tasks
sem := [: |mutex([])\n :]
every put(threads := [], (i := 1 to k, thread
every 1 to m do {
wri... | Give a code snippet in #Icon_and_Unicon
The goal of this task is to create a counting semaphore used to control the execution of a set of concurrent units. This task intends to demonstrate coordination of active concurrent units through the use of a passive concurrent unit. The operations for a counting semaphore are ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Obtain_a_Y_or_N_response | Keyboard input/Obtain a Y or N response |
Task
Obtain a valid Y or N response from the keyboard.
The keyboard should be flushed, so that any outstanding key-presses are removed, preventing any existing Y or N key-press from being evaluated.
The response should be obtained as soon as Y or N are pressed, and there should be no need t... | #Microsoft_Small_Basic | Microsoft Small Basic | 'From:
'Andy Oneill, 2-6-2015, "Small Basic: Key Input,
'" TechNet, https://social.technet.microsoft.com/wiki/contents/articles/29850.small-basic-key-input.aspx, accessed 3-19-2018
GraphicsWindow.DrawText(10, 10, "Hit any key to dump.")
GraphicsWindow.KeyDown = OnKeyDown
Sub OnKeyDown
TextWindow.WriteLine(GraphicsWi... | Give a code snippet in #Microsoft_Small_Basic
Task
Obtain a valid Y or N response from the keyboard.
The keyboard should be flushed, so that any outstanding key-presses are removed, preventing any existing Y or N key-press from being evaluated.
The response should be obtained as soon as Y or ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gaussian_elimination | Gaussian elimination | Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| #Phix | Phix | with javascript_semantics
function gauss_eliminate(sequence a, b)
{a, b} = deep_copy({a,b})
integer n = length(b)
atom tmp
for col=1 to n do
integer m = col
atom mx = a[m][m]
for i=col+1 to n do
tmp = abs(a[i][col])
if tmp>mx then
{m,mx} = ... | Give a code snippet in #Phix
Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Closest-pair_problem | Closest-pair problem |
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Provide a function to find the closest two p... | #Clojure | Clojure |
(defn distance [[x1 y1] [x2 y2]]
(let [dx (- x2 x1), dy (- y2 y1)]
(Math/sqrt (+ (* dx dx) (* dy dy)))))
(defn brute-force [points]
(let [n (count points)]
(when (< 1 n)
(apply min-key first
(for [i (range 0 (dec n)), :let [p1 (nth points i)],
j (range (inc i) n), :... | Give a code snippet in #Clojure
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Provide a f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parse_an_IP_Address | Parse an IP Address | The purpose of this task is to demonstrate parsing of text-format IP addresses, using IPv4 and IPv6.
Taking the following as inputs:
127.0.0.1
The "localhost" IPv4 address
127.0.0.1:80
The "localhost" IPv4 address, with a specified port (80)
::1
The "localhost" IPv6 address
[::1]:80
The "localhost" IPv6... | #Rust | Rust | use std::{
net::{IpAddr, SocketAddr},
str::FromStr,
};
#[derive(Clone, Debug)]
struct Addr {
addr: IpAddr,
port: Option<u16>,
}
impl std::fmt::Display for Addr {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
let ipv = if self.addr.is_ipv4() { "4" } else { "6" };
... | Give a code snippet in #Rust
The purpose of this task is to demonstrate parsing of text-format IP addresses, using IPv4 and IPv6.
Taking the following as inputs:
127.0.0.1
The "localhost" IPv4 address
127.0.0.1:80
The "localhost" IPv4 address, with a specified port (80)
::1
The "localhost" IPv6 address
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Circular_primes | Circular primes | Definitions
A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime.
For example:
1193 is a circular prime, since 1931, 9311 and 3119 are all also prime.
Note that a number which is a cyclic permutation ... | #Kotlin | Kotlin | import java.math.BigInteger
val SMALL_PRIMES = listOf(
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97,
101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199,
211, 223, 227, 229, 233, 239, 241, 251, 257, 263, ... | Give a code snippet in #Kotlin
Definitions
A circular prime is a prime number with the property that the number generated at each intermediate step when cyclically permuting its (base 10) digits will also be prime.
For example:
1193 is a circular prime, since 1931, 9311 and 3119 are all also prime.
Note that a numbe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #XPL0 | XPL0 | include c:\cxpl\codes;
func DotProd(U, V, L);
int U, V, L;
int S, I;
[S:= 0;
for I:= 0 to L-1 do S:= S + U(I)*V(I);
return S;
];
[IntOut(0, DotProd([1, 3, -5], [4, -2, -1], 3));
CrLf(0);
] | Give a code snippet in #XPL0
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strassen%27s_algorithm | Strassen's algorithm | Description
In linear algebra, the Strassen algorithm (named after Volker Strassen), is an algorithm for matrix multiplication.
It is faster than the standard matrix multiplication algorithm and is useful in practice for large matrices, but would be slower than the fastest known algorithms for extremely large ma... | #Raku | Raku | # 20210126 Raku programming solution
use Math::Libgsl::Constants;
use Math::Libgsl::Matrix;
use Math::Libgsl::BLAS;
my @M;
sub SQM (\in) { # create custom sq matrix from CSV
die "Not a ■" if (my \L = in.split(/\,/)).sqrt != (my \size = L.sqrt.Int);
my Math::Libgsl::Matrix \M .= new: size, size;
for ^siz... | Give a code snippet in #Raku
Description
In linear algebra, the Strassen algorithm (named after Volker Strassen), is an algorithm for matrix multiplication.
It is faster than the standard matrix multiplication algorithm and is useful in practice for large matrices, but would be slower than the fastest known alg... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Harshad_or_Niven_series | Harshad or Niven series | The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task is to create a function/method/... | #PL.2FI | PL/I | *process source or(!) xref attributes;
niven: Proc Options(main);
/*********************************************************************
* 08-06.2013 Walter Pachl translated from Rexx
* with a slight improvement: Do j=y+1 By 1;
**************************************************************... | Give a code snippet in #PL.2FI
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jaro_similarity | Jaro similarity | The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that 0 equates to no similarities and 1 is an exact match.
Definition
The... | #Delphi | Delphi | defmodule Jaro do
def distance(s, t) when is_binary(s) and is_binary(t), do:
distance(to_charlist(s), to_charlist(t))
def distance(x, x), do: 1.0
def distance(s, t) do
s_len = length(s)
t_len = length(t)
{s_matches, t_matches, matches} = matching(s, t, s_len, t_len)
if matches == 0 do
0.... | Give a code snippet in #Delphi
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that 0 equates to no similarities and 1 is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pi | Pi |
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal sequence beginning 3.14159265 ...... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
import java.math.BigInteger
runSample(arg)
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) private static
parse arg places .
if places = '' then places = -1
TWO = BigInt... | Give a code snippet in #NetRexx
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal se... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Multiple | Inheritance/Multiple | Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePhone, then write a class Camer... | #Rust | Rust | trait Camera {}
trait MobilePhone {}
trait CameraPhone: Camera + MobilePhone {} | Give a code snippet in #Rust
Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePho... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tau_function | Tau function | Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| #Fermat | Fermat | Func Tau(t) =
if t<3 then Return(t) else
numdiv:=2;
for q = 2 to t\2 do
if Divides(q, t) then numdiv:=numdiv+1 fi;
od;
Return(numdiv);
fi;
.;
for i = 1 to 100 do
!(Tau(i),' ');
od; | Give a code snippet in #Fermat
Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Output | XML/Output | Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element.
As an example, calling ... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
class Program
{
static string CreateXML(Dictionary<string, string> characterRemarks)
{
var remarks = characterRemarks.Select(r => new XElement("Character", r.Value, new XAttribute("Name", r.Key)));
var xm... | Give a code snippet in #C.23
Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> ele... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Scala | Scala | val conf = scala.io.Source.fromFile("config.file").
getLines.
toList.
filter(_.trim.size > 0).
filterNot("#;" contains _(0)).
map(_ split(" ", 2) toList).
map(_ :+ "true" take 2).
map {
s:List[String] => (s(0).toLowerCase, s(1).split(",").map(_.trim).toList)
}.toMap | Give a code snippet in #Scala
The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ... | 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
... | #Clojure | Clojure | (defn transpose [xs]
(loop [ret [], remain xs]
(if (empty? remain)
ret
(recur (conj ret (map first remain))
(filter not-empty (map rest remain))))))
(defn bead-sort [xs]
(->> xs
(map #(repeat % 1))
transpose
transpose
(map #(reduce + %))))
;; This alg... | Give a code snippet in #Clojure
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Clear_the_screen | Terminal control/Clear the screen | Task
Clear the terminal window.
| #Euphoria | Euphoria | clear_screen() | Give a code snippet in #Euphoria
Task
Clear the terminal window.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/String | Literals/String | Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
Here document
Other tasks r... | #HicEst | HicEst | CHARACTER c1='A', c2="B", c3=&C&
CHARACTER str1='single quotes', str2="double quotes", str3*100
str3 = % delimit "Nested 'strings' " if needed % | Give a code snippet in #HicEst
Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greyscale_bars/Display | Greyscale bars/Display | The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha... | #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
int Q, N, W, B, C, Y;
[SetVid($112); \640x480x24 graphics
for Q:= 0 to 4-1 do \quarter of screen
[N:= 8<<Q; \number of bars
W:= 640/N; \width of bar (pixels)
for B:= 0 to N-1 do ... | Give a code snippet in #XPL0
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we ha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Day_of_the_week | Day of the week | A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years between 2008 and 2121 will the 25th of ... | #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
func WeekDay(Year, Month, Day); \Return day of week (0=Sat 1=Sun..6=Fri)
int Year, Month, Day;
[if Month<=2 then [Month:= Month+12; Year:= Year-1];
return rem((Day + (Month+1)*26/10 + Year + Year/4 + Year/100*6 + Year/400) / 7);
]; ... | Give a code snippet in #XPL0
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years between 2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Munching_squares | Munching squares | Render a graphical pattern where each pixel is colored by the value of 'x xor y' from an arbitrary color table.
| #Tcl | Tcl | package require Tk
proc xorImage {img table} {
set data {}
set h [image height $img]
set w [image width $img]
for {set y 0} {$y < $h} {incr y} {
set row {}
for {set x 0} {$x < $w} {incr x} {
lappend row [lindex $table [expr {($x^$y) % [llength $table]}]]
}
lappend data $row
}
$img put... | Give a code snippet in #Tcl
Render a graphical pattern where each pixel is colored by the value of 'x xor y' from an arbitrary color table.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Strong_and_weak_primes | Strong and weak primes |
Definitions (as per number theory)
The prime(p) is the pth prime.
prime(1) is 2
prime(4) is 7
A strong prime is when prime(p) is > [prime(p-1) + prime(p+1)] ÷ 2
A weak prime is when prime(p) is < [prime(p-1) + prime(p+1)] ÷ 2
Note that the defin... | #D | D | import std.algorithm;
import std.array;
import std.range;
import std.stdio;
immutable PRIMES = [
2, 3, 5, 7,
11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97,
101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223... | Give a code snippet in #D
Definitions (as per number theory)
The prime(p) is the pth prime.
prime(1) is 2
prime(4) is 7
A strong prime is when prime(p) is > [prime(p-1) + prime(p+1)] ÷ 2
A weak prime is when prime(p) is < [prime(p-1) + prime(p+1)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Racket | Racket |
#lang racket
(require racket/gui)
(define str (get-text-from-user "Hi" "Enter a string"))
(message-box "Hi" (format "You entered: ~a" str))
(define n (get-text-from-user "Hi" "Enter a number"))
(message-box "Hi" (format "You entered: ~a"
(or (string->number n) "bogus text")))
| Give a code snippet in #Racket
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| 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... | #Dart | Dart | makeAccumulator(s) => (n) => s += n; | Give a code snippet in #Dart
A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values pass... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Break | Loops/Break | Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If the number 10 is never gener... | #Swift | Swift | while true
{
let a = Int(arc4random()) % (20)
print("a: \(a)",terminator: " ")
if (a == 10)
{
break
}
let b = Int(arc4random()) % (20)
print("b: \(b)")
}
| Give a code snippet in #Swift
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pinstripe/Printer | Pinstripe/Printer | The task is to demonstrate the creation of a series of 1 point wide vertical pinstripes with a sufficient number of pinstripes to span the entire width of the printed page (except for the last pinstripe). The pinstripes should alternate one point white, one point black. (Where the printer does not support producing gra... | #Go | Go | package main
import (
"github.com/fogleman/gg"
"log"
"os/exec"
"runtime"
)
var palette = [2]string{
"FFFFFF", // white
"000000", // black
}
func pinstripe(dc *gg.Context) {
w := dc.Width()
h := dc.Height() / 7
for b := 1; b <= 11; b++ {
for x, ci := 0, 0; x < w; x, ... | Give a code snippet in #Go
The task is to demonstrate the creation of a series of 1 point wide vertical pinstripes with a sufficient number of pinstripes to span the entire width of the printed page (except for the last pinstripe). The pinstripes should alternate one point white, one point black. (Where the printer do... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Swift | Swift | Give a code snippet in #Swift
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Averages/Mean_angle | Averages/Mean angle | When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first reading was of 350 degrees and the ... | #Maple | Maple | > [ 350, 10 ] *~ Unit(arcdeg);
[350 [arcdeg], 10 [arcdeg]] | Give a code snippet in #Maple
When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first read... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function... | #Logo | Logo | to varargs [:args]
foreach :args [print ?]
end
(varargs "Mary "had "a "little "lamb)
apply "varargs [Mary had a little lamb] | Give a code snippet in #Logo
Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fusc_sequence | Fusc sequence |
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition starts with unity, not zero. Th... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | package main
import (
"fmt"
"strconv"
)
func fusc(n int) []int {
if n <= 0 {
return []int{}
}
if n == 1 {
return []int{0}
}
res := make([]int, n)
res[0] = 0
res[1] = 1
for i := 2; i < n; i++ {
if i%2 == 0 {
res[i] = res[i/2]
} e... | Give a code snippet in #F.C5.8Drmul.C3.A6
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Inverse_video | Terminal control/Inverse video | Task
Display a word in inverse video (or reverse video) followed by a word in normal video.
| #Kotlin | Kotlin | // version 1.1.2
fun main(args: Array<String>) {
println("\u001B[7mInverse\u001B[m Normal")
} | Give a code snippet in #Kotlin
Task
Display a word in inverse video (or reverse video) followed by a word in normal video.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #D | D | import std.stdio, std.range, std.algorithm, std.typecons, std.conv;
auto properDivisors(in ulong n) pure nothrow @safe /*@nogc*/ {
return iota(1UL, (n + 1) / 2 + 1).filter!(x => n % x == 0 && n != x);
}
enum pDivsSum = (in ulong n) pure nothrow @safe /*@nogc*/ =>
n.properDivisors.sum;
auto aliquot(in ulon... | Give a code snippet in #D
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Elixir | Elixir | {a,_} = IO.gets("Enter your first integer: ") |> Integer.parse
{b,_} = IO.gets("Enter your second integer: ") |> Integer.parse
cond do
a < b ->
IO.puts "#{a} is less than #{b}"
a > b ->
IO.puts "#{a} is greater than #{b}"
a == b ->
IO.puts "#{a} is equal to #{b}"
end | Give a code snippet in #Elixir
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set | Set |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an... | #J | J | union=: ~.@,
intersection=: [ -. -.
difference=: -.
subset=: *./@e.
equality=: -:&(/:~) | Give a code snippet in #J
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Haxe | Haxe | class SelectionSort {
@:generic
public static function sort<T>(arr:Array<T>) {
var len = arr.length;
for (index in 0...len) {
var minIndex = index;
for (remainingIndex in (index+1)...len) {
if (Reflect.compare(arr[minIndex], arr[remainingIndex]) > 0)
minIndex = remainingIndex;
... | Give a code snippet in #Haxe
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/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop body... | #Racket | Racket |
#lang racket
(for ([i (in-range 10 -1 -1)])
(displayln i))
| Give a code snippet in #Racket
Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Incre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Almost_prime | Almost prime | A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, where
k
=
2
{\displaystyl... | #Oforth | Oforth | : kprime?( n k -- b )
| i |
0 2 n for: i [
while( n i /mod swap 0 = ) [ ->n 1+ ] drop
]
k ==
;
: table( k -- [] )
| l |
Array new dup ->l
2 while (l size 10 <>) [ dup k kprime? if dup l add then 1+ ]
drop
; | Give a code snippet in #Oforth
A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_management | Window management | Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of interest may or may not have b... | #C | C |
#include<windows.h>
#include<unistd.h>
#include<stdio.h>
const char g_szClassName[] = "weirdWindow";
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch(msg)
{
case WM_CLOSE:
DestroyWindow(hwnd);
break;
case WM_DESTROY:
PostQ... | Give a code snippet in #C
Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of int... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pig_the_dice_game/Player | Pig the dice game/Player | Pig the dice game/Player
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a dice simulator and scorer of Pig the dice game and add to it the ability to play the game to at least one strategy.
State here the play strategies involved.
Show play dur... | #Nim | Nim | import random, strformat
const MaxPoints = 100
type
Move {.pure.} = enum Roll, Hold
Strategy {.pure.} = enum Rand, Q2Win, AL20, AL20T
# Player description.
Player = ref object
num: Natural
currentScore: Natural
roundScore: Natural
strategy: Strategy
next: Player
# Player list man... | Give a code snippet in #Nim
Pig the dice game/Player
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a dice simulator and scorer of Pig the dice game and add to it the ability to play the game to at least one strategy.
State here the play strate... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #Toka | Toka | 4 cells is-array foo
212 1 foo array.put
51 2 foo array.put
12 3 foo array.put
91 4 foo array.put
[ ( array size -- sum )
>r 0 r> 0 [ over i swap array.get + ] countedLoop nip ] is sum-array
( product )
reset 1 4 0 [ i foo array.get * ] countedLoop . | Give a code snippet in #Toka
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Clojure | Clojure | (import 'javax.swing.JOptionPane)
(let [number (-> "Enter an Integer"
JOptionPane/showInputDialog
Integer/parseInt)
string (JOptionPane/showInputDialog "Enter a String")]
[number string]) | Give a code snippet in #Clojure
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_creation/X11 | Window creation/X11 | Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| #Icon_and_Unicon | Icon and Unicon | procedure main()
W1 := open("X-Window","g","size=250,250","bg=black","fg=red") | stop("unable to open window")
FillRectangle(W1,50,50,150,150)
WDone(W1)
end
link graphics | Give a code snippet in #Icon_and_Unicon
Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the ... | #F.23 | F# | module Soundex
let soundex (s : string) =
let code c =
match c with
| 'B' | 'F' | 'P' | 'V' -> Some('1')
| 'C' | 'G' | 'J' | 'K' | 'Q' | 'S' | 'X' | 'Z' -> Some('2')
| 'D' | 'T' -> Some('3')
| 'L' -> Some('4')
| 'M' | 'N' -> Some('5')
| 'R' -> Some('6')
... | Give a code snippet in #F.23
Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_word | Fibonacci word | The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-1 concatenated with F_wordn-... | #Objeck | Objeck | use Collection;
class FibonacciWord {
function : native : GetEntropy(result : String) ~ Float {
frequencies := IntMap->New();
each(i : result) {
c := result->Get(i);
if(frequencies->Has(c)) {
count := frequencies->Find(c)->As(IntHolder);
count->Set(count->Get() + 1);
}
... | Give a code snippet in #Objeck
The Fibonacci Word may be created in a manner analogous to the Fibonacci Sequence as described here:
Define F_Word1 as 1
Define F_Word2 as 0
Form F_Word3 as F_Word2 concatenated with F_Word1 i.e.: 01
Form F_Wordn as F_Wordn-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem | Primality by Wilson's theorem | Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
| #FreeBASIC | FreeBASIC | function wilson_prime( n as uinteger ) as boolean
dim as uinteger fct=1, i
for i = 2 to n-1
'because (a mod n)*b = (ab mod n)
'it is not necessary to calculate the entire factorial
fct = (fct * i) mod n
next i
if fct = n-1 then return true else return false
end function
for i... | Give a code snippet in #FreeBASIC
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theore... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_operations | Bitwise operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Oberon-2 | Oberon-2 |
MODULE Bitwise;
IMPORT
SYSTEM,
Out;
PROCEDURE Do(a,b: LONGINT);
VAR
x,y: SET;
BEGIN
x := SYSTEM.VAL(SET,a);y := SYSTEM.VAL(SET,b);
Out.String("a and b :> ");Out.Int(SYSTEM.VAL(LONGINT,x * y),0);Out.Ln;
Out.String("a or b :> ");Out.Int(SYSTEM.VAL(LONGINT,x + y),0);Out.Ln;
Out.String("a xor b :> ");Out... | Give a code snippet in #Oberon-2
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 Operatio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dutch_national_flag_problem | Dutch national flag problem |
The Dutch national flag is composed of three coloured bands in the order:
red (top)
then white, and
lastly blue (at the bottom).
The problem posed by Edsger Dijkstra is:
Given a number of red, blue and white balls in random order, arrange them in the order of the colours in the Dutch national fla... | #Erlang | Erlang | -module(dutch).
-export([random_balls/1, is_dutch/1, dutch/1]).
ball(red) -> 1;
ball(white) -> 2;
ball(blue) -> 3.
random_ball() -> lists:nth(random:uniform(3), [red, white, blue]).
random_balls(N) -> random_balls(N,[]).
random_balls(0,L) -> L;
random_balls(N,L) when N > 0 ->
B = random_ball(),
random_ba... | Give a code snippet in #Erlang
The Dutch national flag is composed of three coloured bands in the order:
red (top)
then white, and
lastly blue (at the bottom).
The problem posed by Edsger Dijkstra is:
Given a number of red, blue and white balls in random order, arrange them in the order of the c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Kernighans_large_earthquake_problem | Kernighans large earthquake problem | Brian Kernighan, in a lecture at the University of Nottingham, described a problem on which this task is based.
Problem
You are given a a data file of thousands of lines; each of three `whitespace` separated fields: a date, a one word name and the magnitude of the event.
Example lines from the file would be lines li... | #PHP | PHP | <?php
// make sure filename was specified on command line
if ( ! isset( $argv[1] ) )
die( 'Data file name required' );
// open file and check for success
if ( ! $fh = fopen( $argv[1], 'r' ) )
die ( 'Cannot open file: ' . $argv[1] );
while ( list( $date, $loc, $mag ) = fscanf( $fh, "%s %s %f" ) ) {
if ... | Give a code snippet in #PHP
Brian Kernighan, in a lecture at the University of Nottingham, described a problem on which this task is based.
Problem
You are given a a data file of thousands of lines; each of three `whitespace` separated fields: a date, a one word name and the magnitude of the event.
Example lines fr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ternary_logic | Ternary logic |
This page uses content from Wikipedia. The original article was at Ternary logic. 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 logic, a three-valued logic (also trivalent, ternary, or trinary... | #C.2B.2B | C++ | #include <iostream>
#include <stdlib.h>
class trit {
public:
static const trit False, Maybe, True;
trit operator !() const {
return static_cast<Value>(-value);
}
trit operator &&(const trit &b) const {
return (value < b.value) ? value : b.value;
}
trit operator ||(const t... | Give a code snippet in #C.2B.2B
This page uses content from Wikipedia. The original article was at Ternary logic. 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 logic, a three-valued logic (al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jewels_and_stones | Jewels and stones | Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case letters. However, in the case ... | #Rust | Rust | fn count_jewels(stones: &str, jewels: &str) -> u8 {
let mut count: u8 = 0;
for cur_char in stones.chars() {
if jewels.contains(cur_char) {
count += 1;
}
}
count
}
fn main() {
println!("{}", count_jewels("aAAbbbb", "aA"));
println!("{}", count_jewels("ZZ", "z"));
}
| Give a code snippet in #Rust
Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_Brain**** | Execute Brain**** | Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly implement the following instructions:... | #Arturo | Arturo | ;
; Brainf*ck compiler
; In Arturo
;
Tape: [0]
DataPointer: new 0
InstructionPointer: new 0
; Look for jumps in Code an register them
; in the Jumps table
precomputeJumps: function [][
vstack: new []
jumphash: new #[]
instrPointer: 0
while [instrPointer<CodeLength] [
command: get split C... | Give a code snippet in #Arturo
Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly imple... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Standard_error | Hello world/Standard error | Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out".
The error messages print to ... | #Forth | Forth | outfile-id
stderr to outfile-id
." Goodbye, World!" cr
to outfile-id | Give a code snippet in #Forth
Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out"... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mandelbrot_set | Mandelbrot set | Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| #Arturo | Arturo | inMandelbrot?: function [c][
z: to :complex [0 0]
do.times: 50 [
z: c + z*z
if 4 < abs z -> return false
]
return true
]
mandelbrot: function [settings][
y: 0
while [y < settings\height][
Y: settings\yStart + y * settings\yStep
x: 0
while [x < settings\w... | Give a code snippet in #Arturo
Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Four_bit_adder | Four bit adder | Task
"Simulate" a four-bit adder.
This design can be realized using four 1-bit full adders.
Each of these 1-bit full adders can be built with two half adders and an or gate. ;
Finally a half adder can be made using an xor gate and an and gate.
The xor gate can be made using two nots, two ands ... | #Java | Java | public class GateLogic
{
// Basic gate interfaces
public interface OneInputGate
{ boolean eval(boolean input); }
public interface TwoInputGate
{ boolean eval(boolean input1, boolean input2); }
public interface MultiGate
{ boolean[] eval(boolean... inputs); }
// Create NOT
public static One... | Give a code snippet in #Java
Task
"Simulate" a four-bit adder.
This design can be realized using four 1-bit full adders.
Each of these 1-bit full adders can be built with two half adders and an or gate. ;
Finally a half adder can be made using an xor gate and an and gate.
The xor gate can be made u... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nautical_bell | Nautical bell |
Task
Write a small program that emulates a nautical bell producing a ringing bell pattern at certain times throughout the day.
The bell timing should be in accordance with Greenwich Mean Time, unless locale dictates otherwise.
It is permissible for the program to daemonize, or to slave off a scheduler, and it is per... | #Python | Python | import time, calendar, sched, winsound
duration = 750 # Bell duration in ms
freq = 1280 # Bell frequency in hertz
bellchar = "\u2407"
watches = 'Middle,Morning,Forenoon,Afternoon,First/Last dog,First'.split(',')
def gap(n=1):
time.sleep(n * duration / 1000)
off = gap
def on(n=1):
winsound.Bee... | Give a code snippet in #Python
Task
Write a small program that emulates a nautical bell producing a ringing bell pattern at certain times throughout the day.
The bell timing should be in accordance with Greenwich Mean Time, unless locale dictates otherwise.
It is permissible for the program to daemonize, or to slav... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the ... | #Run_BASIC | Run BASIC | global val$
val$(1) = "BPFV"
val$(2) = "CSGJKQXZ"
val$(3) = "DT"
val$(4) = "L"
val$(5) = "MN"
val$(6) = "R"
' ---------------------------------
' show soundex on these words
' ---------------------------------
w$(1) = "Robert" 'R163
w$(2) = "Rupert" 'R163
w$(3) = "Rubin" 'R150
w$(4) = "moses" 'M... | Give a code snippet in #Run_BASIC
Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
The... | 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... | #Emacs_Lisp | Emacs Lisp | (message "%s" (current-time-string))
;; => "Wed Oct 14 22:21:05 1987" | Give a code snippet in #Emacs_Lisp
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/Probabilistic_choice | Probabilistic choice | Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is invol... | #Erlang | Erlang |
-module(probabilistic_choice).
-export([test/0]).
-define(TRIES, 1000000).
test() ->
Probs =
[{aleph,1/5},
{beth,1/6},
{gimel,1/7},
{daleth,1/8},
{he,1/9},
{waw,1/10},
{zayin,1/11},
{heth,1759/27720}],
random:seed(now()),
Trials =
[get_choice(Probs,random:uniform()) || _ <- list... | Give a code snippet in #Erlang
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because fl... | christopher/rosetta-code |
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