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/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... | #Neko | Neko | /* Repeat a string, in Neko */
var srep = function(s, n) {
var str = ""
while n > 0 {
str += s
n -= 1
}
return str
}
$print(srep("ha", 5), "\n") | Give a code snippet in #Neko
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/List_comprehensions | List comprehensions | A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and the use of map and filter functio... | #OCaml | OCaml | # [? 2 * x | x <- 0 -- max_int ; x * x > 3];;
- : int Enum.t = <abstr> | Give a code snippet in #OCaml
A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Special_variables | Special variables | Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| #jq | jq | $ jq -n -M --arg x 1 '$x|type' # (*)
"string" | Give a code snippet in #jq
Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #Kotlin | Kotlin | // version 1.1.2
fun main(args: Array<String>) {
println("Police Sanitation Fire")
println("------ ---------- ----")
var count = 0
for (i in 2..6 step 2) {
for (j in 1..7) {
if (j == i) continue
for (k in 1..7) {
if (k == i || k == j) continue
... | Give a code snippet in #Kotlin
There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Continued_fraction/Arithmetic/Construct_from_rational_number | Continued fraction/Arithmetic/Construct from rational number | Continued fraction arithmetic
The purpose of this task is to write a function
r
2
c
f
(
i
n
t
{\displaystyle {\mathit {r2cf}}(\mathrm {int} }
N
1
,
i
n
t
{\displaystyle N_{1},\mathrm {int} }
N
2
)
{\displaystyle N_{2})}
, or
r
2
c
f
(
F
r
a
c
t
i
o
n
{\displaystyle {\m... | #Raku | Raku | sub r2cf(Rat $x is copy) {
gather loop {
$x -= take $x.floor;
last unless $x > 0;
$x = 1 / $x;
}
}
say r2cf(.Rat) for <1/2 3 23/8 13/11 22/7 1.41 1.4142136>; | Give a code snippet in #Raku
Continued fraction arithmetic
The purpose of this task is to write a function
r
2
c
f
(
i
n
t
{\displaystyle {\mathit {r2cf}}(\mathrm {int} }
N
1
,
i
n
t
{\displaystyle N_{1},\mathrm {int} }
N
2
)
{\displaystyle N_{2})}
, or
r
2
c
f
(
F
r
a
c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #x86-64_Assembly | x86-64 Assembly |
evenOdd:
mov rax,1
and rax,rdi
ret
| Give a code snippet in #x86-64_Assembly
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is ... | 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.
| #D | D | void main() {
import std.stdio;
enum width = 512, height = 512;
auto f = File("xor_pattern.ppm", "wb");
f.writefln("P6\n%d %d\n255", width, height);
foreach (immutable y; 0 .. height)
foreach (immutable x; 0 .. width) {
immutable c = (x ^ y) & ubyte.max;
immutable... | Give a code snippet in #D
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/Secure_temporary_file | Secure temporary file | Task
Create a temporary file, securely and exclusively (opening it such that there are no possible race conditions).
It's fine assuming local filesystem semantics (NFS or other networking filesystems can have signficantly more complicated semantics for satisfying the "no race conditions" criteria).
The function shou... | #Raku | Raku | use File::Temp;
# Generate a temp file in a temp dir
my ($filename0,$filehandle0) = tempfile;
# specify a template for the filename
# * are replaced with random characters
my ($filename1,$filehandle1) = tempfile("******");
# Automatically unlink files at DESTROY (this is the default)
my ($filename2,$filehandle2)... | Give a code snippet in #Raku
Task
Create a temporary file, securely and exclusively (opening it such that there are no possible race conditions).
It's fine assuming local filesystem semantics (NFS or other networking filesystems can have signficantly more complicated semantics for satisfying the "no race conditions"... | 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 ... | #XLISP | XLISP | (DISPLAY "Goodbye, World!" *ERROR-OUTPUT*) | Give a code snippet in #XLISP
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/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... | #Maple | Maple | > use StringTools in Ord( "A" ); Char( 65 ) end;
65
"A"
| Give a code snippet in #Maple
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).
Conv... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/0-1 | Knapsack problem/0-1 | A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have to last the whole day.
He cre... | #Ada | Ada | with Ada.Text_IO;
with Ada.Strings.Unbounded;
procedure Knapsack_01 is
package US renames Ada.Strings.Unbounded;
type Item is record
Name : US.Unbounded_String;
Weight : Positive;
Value : Positive;
Taken : Boolean;
end record;
type Item_Array is array (Positive range <>) of... | Give a code snippet in #Ada
A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have t... | 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 ... | #Haskell | Haskell | import Data.Time (fromGregorian)
import Data.Time.Calendar.WeekDate (toWeekDate)
--------------------- DAY OF THE WEEK --------------------
isXmasSunday :: Integer -> Bool
isXmasSunday year = 7 == weekDay
where
(_, _, weekDay) = toWeekDate $ fromGregorian year 12 25
--------------------------- TEST ------... | Give a code snippet in #Haskell
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 betwee... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Preserve_screen | Terminal control/Preserve screen |
Task
Clear the screen, output something on the display, and then restore the screen to the preserved state that it was in before the task was carried out.
There is no requirement to change the font or kerning in this task, however character decorations and attributes are expected to be preserved. If the implement... | #Befunge | Befunge | "h9401?["39*>:#,_"...erotser ot >retnE< sserPH["39*>:#,_~$"l9401?["39*>:#,_@ | Give a code snippet in #Befunge
Task
Clear the screen, output something on the display, and then restore the screen to the preserved state that it was in before the task was carried out.
There is no requirement to change the font or kerning in this task, however character decorations and attributes are expected to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Memory_allocation | Memory allocation | Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| #Smalltalk | Smalltalk | handle := ExternalBytes new:size
...
handle free | Give a code snippet in #Smalltalk
Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Comments | Comments | Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| #KonsolScript | KonsolScript | //This is a comment.
//This is another comment.
/* This is a comment too. */
/* This is a
multi-line
comment */ | Give a code snippet in #KonsolScript
Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #Run_BASIC | Run BASIC | ' formats array im() of size ims
for ims = 4 to 6
print :print "--- Size: ";ims;" ---"
Dim im(ims,ims)
For i = 1 To ims
im(i,i) = 1
next
For row = 1 To ims
print "[";
cma$ = ""
For col = 1 To ims
print cma$;im(row, col);
cma$ = ", "
next
print "]"
next
next ims | Give a code snippet in #Run_BASIC
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
Th... | #Wren | Wren | import "/fmt" for Conv
var urlDecode = Fn.new { |enc|
var res = ""
var i = 0
while (i < enc.count) {
var c = enc[i]
if (c == "\%") {
var b = Conv.atoi(enc[i+1..i+2], 16)
res = res + String.fromByte(b)
i = i + 3
} else {
res = res + c
... | Give a code snippet in #Wren
This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded f... | 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... | #Wren | Wren | import "/fmt" for Fmt
import "/math" for Int
var binomial = Fn.new { |n, k|
if (n < 0 || k < 0) Fiber.abort("Arguments must be non-negative integers")
if (n < k) Fiber.abort("The second argument cannot be more than the first.")
if (n == k) return 1
var prod = 1
var i = n - k + 1
while (i <= n)... | Give a code snippet in #Wren
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Move-to-front_algorithm | Move-to-front algorithm | Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful in some compression algorithms... | #PowerShell | PowerShell | Function Test-MTF
{
[CmdletBinding()]
Param
(
[Parameter(Mandatory=$true,Position=0)]
[string]$word,
[Parameter(Mandatory=$false)]
[string]$SymbolTable = 'abcdefghijklmnopqrstuvwxyz'
)
Begin
{
Function Encode
{
Param
(
... | Give a code snippet in #PowerShell
Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is u... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file_on_magnetic_tape | Create a file on magnetic tape | The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| #Nim | Nim | var t = open("/dev/tape", fmWrite)
t.writeln "Hi Tape!"
t.close | Give a code snippet in #Nim
The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Polymorphism | Polymorphism | Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| #JavaScript | JavaScript | /* create new Point in one of these ways:
* var p = new Point(x,y);
* var p = new Point(a_point);
* default value for x,y is 0
*/
function Point() {
var arg1 = arguments[0];
var arg2 = arguments[1];
if (arg1 instanceof Point) {
this.x = arg1.x;
this.y = arg1.y;
}
else {
... | Give a code snippet in #JavaScript
Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #C.2B.2B | C++ | #include <QApplication>
#include <QMainWindow>
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
QMainWindow window;
window.show();
return app.exec();
} | Give a code snippet in #C.2B.2B
Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| 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... | #PL.2FI | PL/I | Carmichael: procedure options (main, reorder); /* 24 January 2014 */
declare (Prime1, Prime2, Prime3, h3, d) fixed binary (31);
put ('Carmichael numbers are:');
do Prime1 = 1 to 61;
do h3 = 2 to Prime1;
d_loop: do d = 1 to h3+Prime1-1;
if (mod((h3+Prime1)*(Prime1-1), d) = 0) &
... | Give a code snippet in #PL.2FI
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 inve... | 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... | #Processing | Processing | float l = 3;
int ints = 13;
void setup() {
size(700, 600);
background(0, 0, 255);
translate(150, 100);
stroke(255);
turn_left(l, ints);
turn_right(l, ints);
}
void turn_right(float l, int ints) {
if (ints == 0) {
line(0, 0, 0, -l);
translate(0, -l);
} else {
turn_left(l, ints-1);
rot... | Give a code snippet in #Processing
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 follow... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Elementary_cellular_automaton/Random_Number_Generator | Elementary cellular automaton/Random Number Generator | Rule 30 is considered to be chaotic enough to generate good pseudo-random numbers. As a matter of fact, rule 30 is used by the Mathematica software for its default random number generator.
Steven Wolfram's recommendation for random number generation from rule 30 consists in extracting successive bits in a fixed positi... | #Phix | Phix | with javascript_semantics
--string s = ".........#.........", --(original)
string s = "...............................#"&
"................................",
--string s = "#"&repeat('.',100), -- [2]
t=s, r = "........"
integer rule = 30, k, l = length(s), w = 0
for i=1 to 8 do
r[i] = iff(mod(ru... | Give a code snippet in #Phix
Rule 30 is considered to be chaotic enough to generate good pseudo-random numbers. As a matter of fact, rule 30 is used by the Mathematica software for its default random number generator.
Steven Wolfram's recommendation for random number generation from rule 30 consists in extracting suc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nth_root | Nth root | Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| #C.2B.2B | C++ | double NthRoot(double m_nValue, double index, double guess, double pc)
{
double result = guess;
double result_next;
do
{
result_next = (1.0/index)*((index-1.0)*result+(m_nValue)/(pow(result,(index-1.0))));
result = result_next;
pc--;
}while(pc>1);
... | Give a code snippet in #C.2B.2B
Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/CUSIP | CUSIP |
This page uses content from Wikipedia. The original article was at CUSIP. 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)
A CUSIP is a nine-character alphanumeric code that identifies a North A... | #AppleScript | AppleScript | use AppleScript version "2.4"
use framework "Foundation"
use scripting additions
-- isCusip :: String -> Bool
on isCusip(s)
set cs to "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*&#"
set ns to mapMaybe(elemIndex(cs), s)
script go
on |λ|(f, x)
set fx to apply(f, x)
(fx div 10) ... | Give a code snippet in #AppleScript
This page uses content from Wikipedia. The original article was at CUSIP. 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)
A CUSIP is a nine-character alphan... | 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 |... | #Aikido | Aikido |
const str = "abcdefg"
var n = 2
var m = 3
println (str[n:n+m-1]) // pos 2 length 3
println (str[n:]) // pos 2 to end
println (str >> 1) // remove last character
var p = find (str, 'c')
println (str[p:p+m-1]) // from pos of p length 3
var s = find (str, "bc")
println (str[s, s+m-1]) // pos ... | Give a code snippet in #Aikido
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/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... | #Axe | Axe | 99→B
While B
Disp B▶Dec," BOTTLES OF","BEER ON THE WALL"
Disp B▶Dec," BOTTLES OF","BEER",i,i
getKeyʳ
Disp "TAKE ONE DOWN",i,"PASS IT AROUND",i
B--
Disp B▶Dec," BOTTLES OF","BEER ON THE WALL",i
getKeyʳ
End | Give a code snippet in #Axe
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 b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #Perl | Perl | use 5.014;
use Math::Algebra::Symbols;
sub bernoulli_number {
my ($n) = @_;
return 0 if $n > 1 && $n % 2;
my @A;
for my $m (0 .. $n) {
$A[$m] = symbols(1) / ($m + 1);
for (my $j = $m ; $j > 0 ; $j--) {
$A[$j - 1] = $j * ($A[$j - 1] - $A[$j]);
}
}
ret... | Give a code snippet in #Perl
In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Enumerations | Enumerations | Task
Create an enumeration of constants with and without explicit values.
| #MATLAB_.2F_Octave | MATLAB / Octave | stuff = {'apple', [1 2 3], 'cherry',1+2i}
stuff =
'apple' [1x3 double] 'cherry' [1.000000000000000 + 2.000000000000000i] | Give a code snippet in #MATLAB_.2F_Octave
Task
Create an enumeration of constants with and without explicit values.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Rock-paper-scissors | Rock-paper-scissors | Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner is decided by a set of rules:
... | #Elixir | Elixir | defmodule Rock_paper_scissors do
def play, do: loop([1,1,1])
defp loop([r,p,s]=odds) do
IO.gets("What is your move? (R,P,S,Q) ") |> String.upcase |> String.first
|> case do
"Q" -> IO.puts "Good bye!"
human when human in ["R","P","S"] ->
IO.puts "Your move is #{play_to_s... | Give a code snippet in #Elixir
Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winne... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler%27s_identity | Euler's identity |
This page uses content from Wikipedia. The original article was at Euler's_identity. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In mathematics, Euler's identity is the equality:
... | #F.23 | F# |
printfn "-1 + 1 = %d" (-1+1)
| Give a code snippet in #F.23
This page uses content from Wikipedia. The original article was at Euler's_identity. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In mathematics, Euler's identity i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #Picat | Picat | s(N) = sum([1.0/K**2 : K in 1..N]). | Give a code snippet in #Picat
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gray_code | Gray code | Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are many possible Gray codes. The follow... | #Action.21 | Action! | PROC ToBinaryStr(BYTE n CHAR ARRAY s)
BYTE i
s(0)=8 i=8
SetBlock(s+1,8,'0)
WHILE n
DO
s(i)=(n&1)+'0
n==RSH 1
i==-1
OD
RETURN
PROC PrintB2(BYTE n)
IF n<10 THEN Put(32) FI
PrintB(n)
RETURN
PROC PrintBin5(BYTE n)
CHAR ARRAY s(9),sub(6)
ToBinaryStr(n,s)
SCopyS(sub,s,4,s(0))
Print... | Give a code snippet in #Action.21
Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Descending_primes | Descending primes | Generate and show all primes with strictly descending decimal digits.
See also
OEIS:A052014 - Primes with distinct digits in descending order
Related
Ascending primes
| #AWK | AWK |
# syntax: GAWK -f DESCENDING_PRIMES.AWK
BEGIN {
start = 1
stop = 99999999
for (i=start; i<=stop; i++) {
leng = length(i)
flag = 1
for (j=1; j<leng; j++) {
if (substr(i,j,1) <= substr(i,j+1,1)) {
flag = 0
break
}
}
if (flag) {
if (is... | Give a code snippet in #AWK
Generate and show all primes with strictly descending decimal digits.
See also
OEIS:A052014 - Primes with distinct digits in descending order
Related
Ascending primes
| christopher/rosetta-code | |
http://rosettacode.org/wiki/CUSIP | CUSIP |
This page uses content from Wikipedia. The original article was at CUSIP. 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)
A CUSIP is a nine-character alphanumeric code that identifies a North A... | #langur | langur | val .isCusip = f(.s) {
if not isString(.s) or len(.s) != 9 {
return false
}
val .basechars = cp2s('0'..'9') ~ cp2s('A'..'Z') ~ "*@#"
val .sum = for[=0] .i of 8 {
var .v = index(s2s(.s, .i), .basechars)
if not .v: return false
.v = .v[1]-1
if .i div 2: .v x= 2
... | Give a code snippet in #langur
This page uses content from Wikipedia. The original article was at CUSIP. 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)
A CUSIP is a nine-character alphanumeri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #Swift | Swift | class Node<T>{
var data:T?=nil
var next:Node?=nil
init(input:T){
data=input
next=nil
}
}
| Give a code snippet in #Swift
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element def... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Nested | Loops/Nested | Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.
Specifically, this task als... | #Smalltalk | Smalltalk | |i|
i := 1.
[:exit |
Transcript showCR:i.
i == 5 ifTrue:[ exit value:'stopped' ].
i := i + 1.
] loopWithExit | Give a code snippet in #Smalltalk
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/General_FizzBuzz | General FizzBuzz | Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be ... | #Forth | Forth | \ gfb.fs - generalized fizz buzz
: times ( xt n -- )
BEGIN dup WHILE
1- over swap 2>r execute 2r>
REPEAT
2drop
;
\ 'Domain Specific Language' compiling words
\ -- First comment: stack-effect at compile-time
\ -- Second comment: stack efect of compiled sequence
: ]+[ ( u ca u -- ) ( u f -- u f' )
2>r >r ]
]]... | Give a code snippet in #Forth
Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along wit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack_traces | Stack traces | Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the platform) the current call stack.... | #BASIC | BASIC | 100 DEF PROC callstack
110 ON ERROR GOTO 1000
120 FOR i=1 TO 100
130 POP lnum
140 LIST lnum TO lnum
150 NEXT i
190 END PROC
1000 PRINT "End of stack"
1010 STOP
| Give a code snippet in #BASIC
Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the pl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_subsequence | Longest common subsequence | Introduction
Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string.
The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings.
Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be strings drawn from an alphabet Σ of ... | #Bracmat | Bracmat | ( LCS
= A a ta B b tb prefix
. !arg:(?prefix.@(?A:%?a ?ta).@(?B:%?b ?tb))
& ( !a:!b&LCS$(!prefix !a.!ta.!tb)
| LCS$(!prefix.!A.!tb)&LCS$(!prefix.!ta.!B)
)
| !prefix:? ([>!max:[?max):?lcs
|
)
& 0:?max
& :?lcs
& LCS$(.thisisatest.testing123testing)
& out$(max !max ... | Give a code snippet in #Bracmat
Introduction
Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string.
The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings.
Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be str... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #HolyC | HolyC | F64 a = 0 ` 0;
Print("0 ` 0 = %5.3f\n", a); | Give a code snippet in #HolyC
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_join | Hash join | An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash join" algorithm, and demonstrate tha... | #Nim | Nim | import strformat, tables
type
Data1 = tuple[value: int; key: string]
Data2 = tuple[key: string; value: string]
proc `$`(d: Data1 | Data2): string = &"({d[0]}, {d[1]})"
iterator hashJoin(table1: openArray[Data1]; table2: openArray[Data2]): tuple[a: Data1; b: Data2] =
# Hash phase.
var h: Table[string, seq[... | Give a code snippet in #Nim
An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash join" a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #ALGOL_68 | ALGOL 68 | BEGIN # find the last Friday in each month of a year #
# returns true if year is a leap year, false otherwise #
# assumes year is in the Gregorian Calendar #
PROC is leap year = ( INT year )BOOL:
year MOD 400 = 0 OR ( year MOD 4 = 0 AND year MOD 100 /= 0 );
# ... | Give a code snippet in #ALGOL_68
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Yorick | Yorick | for(i = 1; i <= 100; i++) {
if(i % 3 == 0)
write, format="%s", "Fizz";
if(i % 5 == 0)
write, format="%s", "Buzz";
if(i % 3 && i % 5)
write, format="%d", i;
write, "";
} | Give a code snippet in #Yorick
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Kronecker_product_based_fractals | Kronecker product based fractals | This task is based on Kronecker product of two matrices.
If your language has no a built-in function for such product then you need to implement it first.
The essence of fractals is self-replication (at least, self-similar replications).
So, using n times self-product of the matrix (filled with 0/1) we ... | #C | C |
#include<graphics.h>
#include<stdlib.h>
#include<stdio.h>
typedef struct{
int row, col;
}cell;
int ROW,COL,SUM=0;
unsigned long raiseTo(int base,int power){
if(power==0)
return 1;
else
return base*raiseTo(base,power-1);
}
cell* kroneckerProduct(char* inputFile,int power){
FILE*... | Give a code snippet in #C
This task is based on Kronecker product of two matrices.
If your language has no a built-in function for such product then you need to implement it first.
The essence of fractals is self-replication (at least, self-similar replications).
So, using n times self-product of the matri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm | Bitmap/Midpoint circle algorithm | Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| #BBC_BASIC | BBC BASIC | Width% = 200
Height% = 200
REM Set window size:
VDU 23,22,Width%;Height%;8,16,16,128
REM Draw circles:
PROCcircle(100,100,40, 0,0,0)
PROCcircle(100,100,80, 255,0,0)
END
DEF PROCcircle(cx%,cy%,r%,R%,G%,B%)
LOCAL f%, x%, y%, ddx%, ddy%
f% = 1 - r% : ... | Give a code snippet in #BBC_BASIC
Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #ERRE | ERRE |
PROGRAM ULAM
!$DOUBLE
PROCEDURE HAILSTONE(X,PRT%->COUNT)
COUNT=1
IF PRT% THEN PRINT(X,) END IF
REPEAT
IF X/2<>INT(X/2) THEN
X=X*3+1
ELSE
X=X/2
END IF
IF PRT% THEN PRINT(X,) END IF
COUNT=COUNT+1
UNTIL X=1
IF PRT% THEN PRINT END IF
END PROCEDURE
B... | Give a code snippet in #ERRE
The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #C.23 | C# | using System;
class ColumnAlignerProgram
{
delegate string Justification(string s, int width);
static string[] AlignColumns(string[] lines, Justification justification)
{
const char Separator = '$';
// build input table and calculate columns count
string[][] table = new string[line... | Give a code snippet in #C.23
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Largest_int_from_concatenated_ints | Largest int from concatenated ints | Task
Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer.
Use the following two sets of integers as tests and show your program output here.
{1, 34, 3, 98, 9, 76, 45, 4}
{54,... | #J | J | maxlen=: [: >./ #&>
maxnum=: (0 ". ;)@(\: maxlen $&> ])@(8!:0) | Give a code snippet in #J
Task
Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer.
Use the following two sets of integers as tests and show your program output here.
{1, 34, 3... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set_puzzle | Set puzzle | Set Puzzles are created with a deck of cards from the Set Game™. The object of the puzzle is to find sets of 3 cards in a rectangle of cards that have been dealt face up.
There are 81 cards in a deck.
Each card contains a unique variation of the following four features: color, symbol, number and shading.
there are... | #Raku | Raku | enum Color (red => 0o1000, green => 0o2000, purple => 0o4000);
enum Count (one => 0o100, two => 0o200, three => 0o400);
enum Shape (oval => 0o10, squiggle => 0o20, diamond => 0o40);
enum Style (solid => 0o1, open => 0o2, striped => 0o4);
my @deck = Color.enums X Count.enums X Shape.enums X Style.enu... | Give a code snippet in #Raku
Set Puzzles are created with a deck of cards from the Set Game™. The object of the puzzle is to find sets of 3 cards in a rectangle of cards that have been dealt face up.
There are 81 cards in a deck.
Each card contains a unique variation of the following four features: color, symbol, n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Totient_function | Totient function | The totient function is also known as:
Euler's totient function
Euler's phi totient function
phi totient function
Φ function (uppercase Greek phi)
φ function (lowercase Greek phi)
Definitions (as per number theory)
The totient function:
counts the integers up to a given positiv... | #Ada | Ada | with Ada.Text_IO;
with Ada.Integer_Text_IO;
procedure Totient is
function Totient (N : in Integer) return Integer is
Tot : Integer := N;
I : Integer;
N2 : Integer := N;
begin
I := 2;
while I * I <= N2 loop
if N2 mod I = 0 then
while N2 mod I = 0 loop
... | Give a code snippet in #Ada
The totient function is also known as:
Euler's totient function
Euler's phi totient function
phi totient function
Φ function (uppercase Greek phi)
φ function (lowercase Greek phi)
Definitions (as per number theory)
The totient function:
counts the i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tarjan | Tarjan |
This page uses content from Wikipedia. The original article was at Graph. 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)
Tarjan's algorithm is an algorithm in graph theory for finding the strongly... | #Julia | Julia | using LightGraphs
edge_list=[(1,2),(3,1),(6,3),(6,7),(7,6),(2,3),(4,2),(4,3),(4,5),(5,6),(5,4),(8,5),(8,8),(8,7)]
grph = SimpleDiGraph(Edge.(edge_list))
tarj = strongly_connected_components(grph)
inzerobase(arrarr) = map(x -> sort(x .- 1, rev=true), arrarr)
println("Results in the zero-base scheme: $(inzeroba... | Give a code snippet in #Julia
This page uses content from Wikipedia. The original article was at Graph. 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)
Tarjan's algorithm is an algorithm in graph ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jensen%27s_Device | Jensen's Device | Jensen's Device
You are encouraged to solve this task according to the task description, using any language you may know.
This task is an exercise in call by name.
Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the ALGOL 60 Report.
The following pr... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | sum[term_, i_, lo_, hi_] := Block[{temp = 0},
Do[temp = temp + term, {i, lo, hi}];
temp];
SetAttributes[sum, HoldFirst]; | Give a code snippet in #Mathematica_.2F_Wolfram_Language
Jensen's Device
You are encouraged to solve this task according to the task description, using any language you may know.
This task is an exercise in call by name.
Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Je... | 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.
| #BaCon | BaCon | COLOR INVERSE
PRINT "a word"
COLOR RESET
PRINT "a word" | Give a code snippet in #BaCon
Task
Display a word in inverse video (or reverse video) followed by a word in normal video.
| 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 ... | #Ursala | Ursala | #import int
dot = sum:-0+ product*p
#cast %z
test = dot(<1,3,-5>,<4,-2,-1>) | Give a code snippet in #Ursala
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, -... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #C.2B.2B | C++ | #include<cstdio>
int main(){char n[]=R"(#include<cstdio>
int main(){char n[]=R"(%s%c";printf(n,n,41);})";printf(n,n,41);} | Give a code snippet in #C.2B.2B
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sexy_primes | Sexy primes |
This page uses content from Wikipedia. The original article was at Sexy_prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In mathematics, sexy primes are prime numbers that differ from each ot... | #AWK | AWK |
# syntax: GAWK -f SEXY_PRIMES.AWK
BEGIN {
cutoff = 1000034
for (i=1; i<=cutoff; i++) {
n1 = i
if (is_prime(n1)) {
total_primes++
if ((n2 = n1 + 6) > cutoff) { continue }
if (is_prime(n2)) {
save(2,5,n1 FS n2)
if ((n3 = n2 + 6) > cutoff) { continue }
... | Give a code snippet in #AWK
This page uses content from Wikipedia. The original article was at Sexy_prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In mathematics, sexy primes are prime num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Short-circuit_evaluation | Short-circuit evaluation | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable resources without side effects, an... | #C.2B.2B | C++ | #include <iostream>
bool a(bool in)
{
std::cout << "a" << std::endl;
return in;
}
bool b(bool in)
{
std::cout << "b" << std::endl;
return in;
}
void test(bool i, bool j) {
std::cout << std::boolalpha << i << " and " << j << " = " << (a(i) && b(j)) << std::endl;
std::cout << std::boolalpha ... | Give a code snippet in #C.2B.2B
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #CLU | CLU | series_sum = proc (from, to: int,
fn: proctype (real) returns (real))
returns (real)
sum: real := 0.0
for i: int in int$from_to(from, to) do
sum := sum + fn(real$i2r(i))
end
return(sum)
end series_sum
one_over_k_squared = proc (k: real) returns (real)
retur... | Give a code snippet in #CLU
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Graphical | Hello world/Graphical |
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| #Vedit_macro_language | Vedit macro language | Statline_Message("Goodbye, World!") | Give a code snippet in #Vedit_macro_language
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack_traces | Stack traces | Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the platform) the current call stack.... | #Wren | Wren | var func2 = Fn.new {
Fiber.abort("Forced error.")
}
var func1 = Fn.new {
func2.call()
}
func1.call() | Give a code snippet in #Wren
Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the pla... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Atomic_updates | Atomic updates |
Task
Define a data type consisting of a fixed number of 'buckets', each containing a nonnegative integer value, which supports operations to:
get the current value of any bucket
remove a specified amount from one specified bucket and add it to another, preserving the total of all bucket values, and clamping the t... | #Perl | Perl | use strict;
use 5.10.0;
use threads 'yield';
use threads::shared;
my @a :shared = (100) x 10;
my $stop :shared = 0;
sub pick2 {
my $i = int(rand(10));
my $j;
$j = int(rand(10)) until $j != $i;
($i, $j)
}
sub even {
lock @a;
my ($i, $j) = pick2;
my $sum = $a[$i] + $a[$j];
$a[$i] = int($sum / 2);
$a[$j] ... | Give a code snippet in #Perl
Task
Define a data type consisting of a fixed number of 'buckets', each containing a nonnegative integer value, which supports operations to:
get the current value of any bucket
remove a specified amount from one specified bucket and add it to another, preserving the total of all buc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sockets | Sockets | For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket.
Catching any exceptions or errors is not required.
| #Nanoquery | Nanoquery | import Nanoquery.Net
p = new(Port)
p.connect("localhost", 256)
p.write("hello socket world")
p.close() | Give a code snippet in #Nanoquery
For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket.
Catching any exceptions or errors is not required.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Arithmetic_mean | Averages/Arithmetic mean | Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin... | #jq | jq | add/length | Give a code snippet in #jq
Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an establi... | 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 ... | #BASIC256 | BASIC256 | # Begin Case / Case / End Case, Do / Until, If Then, While / End While
begin case
case boolean_expr
statement(s)
case boolean_expr
statement(s)
else
statement(s)
end case
do
statement(s)
until boolean_expr
if booleanexpr then
statement(s)
end if
if booleanexpr then
statem... | Give a code snippet in #BASIC256
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Comm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Munchausen_numbers | Munchausen numbers | A Munchausen number is a natural number n the sum of whose digits (in base 10), each raised to the power of itself, equals n.
(Munchausen is also spelled: Münchhausen.)
For instance: 3435 = 33 + 44 + 33 + 55
Task
Find all Munchausen numbers between 1 and 5000.
Also see
The OEIS entry: A046253
The ... | #min | min | (dup string "" split (int dup pow) (+) map-reduce ==) :munchausen?
1 :i
(i 5000 <=) ((i munchausen?) (i puts!) when i succ @i) while | Give a code snippet in #min
A Munchausen number is a natural number n the sum of whose digits (in base 10), each raised to the power of itself, equals n.
(Munchausen is also spelled: Münchhausen.)
For instance: 3435 = 33 + 44 + 33 + 55
Task
Find all Munchausen numbers between 1 and 5000.
Also see
T... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string | Tokenize a string | Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks related to string operations:
Me... | #Clojure | Clojure | (apply str (interpose "." (.split #"," "Hello,How,Are,You,Today"))) | Give a code snippet in #Clojure
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Padovan_n-step_number_sequences | Padovan n-step number sequences | As the Fibonacci sequence expands to the Fibonacci n-step number sequences; We similarly expand the Padovan sequence to form these Padovan n-step number sequences.
The Fibonacci-like sequences can be defined like this:
For n == 2:
start: 1, 1
Recurrence: R(n, x) = R(n, x-1) + R(n, x-2); for n ==... | #Phix | Phix | with javascript_semantics
function padovann(integer n,t)
if n<2 or t<3 then return repeat(1,t) end if
sequence p = padovann(n-1, t)
for i=n+2 to t do
p[i] = sum(p[i-n-1..i-2])
end for
return p
end function
constant t = 15,
fmt = "%d: %d %d %d %d %d %d %d %2d %2d %2d %2d %2d %3d %3d %3d\n"... | Give a code snippet in #Phix
As the Fibonacci sequence expands to the Fibonacci n-step number sequences; We similarly expand the Padovan sequence to form these Padovan n-step number sequences.
The Fibonacci-like sequences can be defined like this:
For n == 2:
start: 1, 1
Recurrence: R(n, x) = R... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sylvester%27s_sequence | Sylvester's sequence |
This page uses content from Wikipedia. The original article was at Sylvester's sequence. 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, Sylvester's sequence is an integer sequenc... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | Rest[Nest[Append[#, (Times @@ #) + 1] &, {1}, 10]]
N[Total[1/%], 250] | Give a code snippet in #Mathematica.2FWolfram_Language
This page uses content from Wikipedia. The original article was at Sylvester's sequence. 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 n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_composition | Function composition | Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function g to x.
Example
compose... | #Fantom | Fantom |
class Compose
{
static |Obj -> Obj| compose (|Obj -> Obj| fn1, |Obj -> Obj| fn2)
{
return |Obj x -> Obj| { fn2 (fn1 (x)) }
}
public static Void main ()
{
double := |Int x -> Int| { 2 * x }
|Int -> Int| quad := compose(double, double)
echo ("Double 3 = ${double(3)}")
echo ("Quadruple 3 ... | Give a code snippet in #Fantom
Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function g ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Base64_decode_data | Base64 decode data | See Base64 encode data.
Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file.
When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with incorrect padding. Obviously... | #FreeBASIC | FreeBASIC | Dim Shared As String B64
B64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" & _
"abcdefghijklmnopqrstuvwxyz" & _
"0123456789+/"
Function MIMEDecode(s As String ) As Integer
If Len(s) Then
MIMEdecode = Instr(B64,s) - 1
Else
MIMEdecode = -1
End If
End Function
Function Decode64(s As String) As String
... | Give a code snippet in #FreeBASIC
See Base64 encode data.
Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file.
When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed outpu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #TUSCRIPT | TUSCRIPT |
$$ MODE TUSCRIPT
-- size of file input.txt
file="input.txt"
ERROR/STOP OPEN (file,READ,-std-)
file_size=BYTES ("input.txt")
ERROR/STOP CLOSE (file)
-- size of file x:/input.txt
ERROR/STOP OPEN (file,READ,x)
file_size=BYTES (file)
ERROR/STOP CLOSE (file)
| Give a code snippet in #TUSCRIPT
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #Delphi | Delphi | proc nonrec main() void:
byte DOORS = 100;
[DOORS+1] bool door_open;
unsigned DOORS i, j;
/* make sure all doors are closed */
for i from 1 upto DOORS do door_open[i] := false od;
/* pass through the doors */
for i from 1 upto DOORS do
for j from i by i upto DOORS do
... | Give a code snippet in #Delphi
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, .... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One-dimensional_cellular_automata | One-dimensional cellular automata | Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.
If, in the follow... | #Arturo | Arturo | evolve: function [arr][
ary: [0] ++ arr ++ [0]
ret: new []
loop 1..(size ary)-2 'i [
a: ary\[i-1]
b: ary\[i]
c: ary\[i+1]
if? 2 = a+b+c -> 'ret ++ 1
else -> 'ret ++ 0
]
ret
]
printIt: function [arr][
print replace replace join map arr => [to :... | Give a code snippet in #Arturo
Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the curren... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_substring | Longest common substring | Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecutive characters within a string.... | #Action.21 | Action! | BYTE Func Equals(CHAR ARRAY a,b)
BYTE i
IF a(0)#b(0) THEN
RETURN (0)
FI
FOR i=1 TO a(0)
DO
IF a(i)#b(i) THEN
RETURN (0)
FI
OD
RETURN (1)
PROC Lcs(CHAR ARRAY a,b,res)
CHAR ARRAY t(100)
BYTE i,j,len
IF a(0)<b(0) THEN
len=a(0)
ELSE
len=b(0)
FI
WHILE len>0
DO
... | Give a code snippet in #Action.21
Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are cons... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle | Constrained random points on a circle | Task
Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that
10
≤
x
2
+
y
2
≤
15
{\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15}
.
Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of point... | #Liberty_BASIC | Liberty BASIC | ' RC Constrained Random Points on a Circle
nomainwin
WindowWidth =400
WindowHeight =430
open "Constrained Random Points on a Circle" for graphics_nsb as #w
#w "trapclose [quit]"
#w "down ; size 7 ; color red ; fill black"
for i =1 to 1000
do
x =int( 30 *rnd( 1)) -15
y =int( 30 *rnd( 1)) -15
l... | Give a code snippet in #Liberty_BASIC
Task
Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that
10
≤
x
2
+
y
2
≤
15
{\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15}
.
Then display/plot them. The outcome should be a "fu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Enumerations | Enumerations | Task
Create an enumeration of constants with and without explicit values.
| #Bracmat | Bracmat | fruits=apple+banana+cherry; | Give a code snippet in #Bracmat
Task
Create an enumeration of constants with and without explicit values.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_directory | Empty directory | Starting with a path to some directory, determine whether the directory is empty.
An empty directory contains no files nor subdirectories.
With Unix or Windows systems, every directory contains an entry for “.” and almost every directory contains “..” (except for a root directory); an empty directory contains no other... | #Factor | Factor | USE: io.directories
: empty-directory? ( path -- ? ) directory-entries empty? ; | Give a code snippet in #Factor
Starting with a path to some directory, determine whether the directory is empty.
An empty directory contains no files nor subdirectories.
With Unix or Windows systems, every directory contains an entry for “.” and almost every directory contains “..” (except for a root directory); an e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/QR_decomposition | QR decomposition | Any rectangular
m
×
n
{\displaystyle m\times n}
matrix
A
{\displaystyle {\mathit {A}}}
can be decomposed to a product of an orthogonal matrix
Q
{\displaystyle {\mathit {Q}}}
and an upper (right) triangular matrix
R
{\displaystyle {\mathit {R}}}
, as described in QR decompositi... | #Phix | Phix | -- demo/rosettacode/QRdecomposition.exw
with javascript_semantics
function matrix_mul(sequence a, b)
integer arows = ~a, acols = ~a[1],
brows = ~b, bcols = ~b[1]
if acols!=brows then return 0 end if
sequence c = repeat(repeat(0,bcols),arows)
for i=1 to arows do
for j=1 to bcols do
... | Give a code snippet in #Phix
Any rectangular
m
×
n
{\displaystyle m\times n}
matrix
A
{\displaystyle {\mathit {A}}}
can be decomposed to a product of an orthogonal matrix
Q
{\displaystyle {\mathit {Q}}}
and an upper (right) triangular matrix
R
{\displaystyle {\mathit {R}}}
, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Lua | Lua | function ack(M,N)
if M == 0 then return N + 1 end
if N == 0 then return ack(M-1,1) end
return ack(M-1,ack(M, N-1))
end | Give a code snippet in #Lua
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rock-paper-scissors | Rock-paper-scissors | Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner is decided by a set of rules:
... | #NS-HUBASIC | NS-HUBASIC | 10 COMPUTER=RND(3)+1
20 COMPUTER$="ROCK"
30 IF COMPUTER=2 THEN COMPUTER$="PAPER"
40 IF COMPUTER=3 THEN COMPUTER$="SCISSORS"
50 INPUT "ROCK, PAPER OR SCISSORS? ",HUMAN$
60 IF HUMAN$="ROCK" THEN GOTO 100
70 IF HUMAN$="PAPER" THEN GOTO 100
80 IF HUMAN$="SCISSORS" THEN GOTO 100
90 PRINT "INVALID GUESS. TRY AGAIN.": GOTO 50... | Give a code snippet in #NS-HUBASIC
Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Babbage_problem | Babbage problem |
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Computers, second edition, 1970, p.... | #SequenceL | SequenceL | main() := babbage(0);
babbage(current) :=
current when current * current mod 1000000 = 269696
else
babbage(current + 1); | Give a code snippet in #SequenceL
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Prime_conspiracy | Prime conspiracy | A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferences about the final digits of ... | #Sidef | Sidef | var primes = (^Inf -> lazy.grep{.is_prime})
var upto = 1e6
var conspiracy = Hash()
primes.first(upto+1).reduce { |a,b|
var d = b%10
conspiracy{"#{a} → #{d}"} := 0 ++
d
}
for k,v in (conspiracy.sort_by{|k,_v| k }) {
printf("%s count: %6s\tfrequency: %2.2f %\n", k, v.commify, v / upto * 100)
} | Give a code snippet in #Sidef
A recent discovery, quoted from Quantamagazine (March 13, 2016):
Two mathematicians have uncovered a simple, previously unnoticed property of
prime numbers — those numbers that are divisible only by 1 and themselves.
Prime numbers, it seems, have decided preferen... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_directory | Empty directory | Starting with a path to some directory, determine whether the directory is empty.
An empty directory contains no files nor subdirectories.
With Unix or Windows systems, every directory contains an entry for “.” and almost every directory contains “..” (except for a root directory); an empty directory contains no other... | #BaCon | BaCon | FUNCTION check$(dir$)
IF FILEEXISTS(dir$) THEN
RETURN IIF$(LEN(WALK$(dir$, 127, ".+", FALSE)), " is NOT empty.", " is empty." )
ELSE
RETURN " doesn't exist."
ENDIF
ENDFUNCTION
dir$ = "bla"
PRINT "Directory '", dir$, "'", check$(dir$)
dir$ = "/mnt"
PRINT "Directory '", dir$, "'", chec... | Give a code snippet in #BaCon
Starting with a path to some directory, determine whether the directory is empty.
An empty directory contains no files nor subdirectories.
With Unix or Windows systems, every directory contains an entry for “.” and almost every directory contains “..” (except for a root directory); an em... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hilbert_curve | Hilbert curve |
Task
Produce a graphical or ASCII-art representation of a Hilbert curve of at least order 3.
| #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "draw.s7i";
include "keybd.s7i";
const integer: delta is 8;
const proc: drawDown (inout integer: x, inout integer: y, in integer: n) is forward;
const proc: drawUp (inout integer: x, inout integer: y, in integer: n) is forward;
const proc: drawRight (inout integer: x, inout i... | Give a code snippet in #Seed7
Task
Produce a graphical or ASCII-art representation of a Hilbert curve of at least order 3.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list | Search a list | Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that has multiple occurrences in ... | #Yabasic | Yabasic | list$ = "mouse,hat,cup,deodorant,television,soap,methamphetamine,severed cat heads,cup"
dim item$(1)
n = token(list$, item$(), ",")
line input "Enter string to search: " line$
for i = 1 to n
if line$ = item$(i) then
if not t print "First index for ", line$, ": ", i
t = i
j = j + 1
... | Give a code snippet in #Yabasic
Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle ... | 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
... | #Ruby | Ruby | require "prime"
smarandache = Enumerator.new do|y|
prime_digits = [2,3,5,7]
prime_digits.each{|pr| y << pr} # yield the below-tens
(1..).each do |n|
prime_digits.repeated_permutation(n).each do |perm|
c = perm.join.to_i * 10
y << c + 3 if (c+3).prime?
y << c + 7 if (c+7).prime?
end
... | Give a code snippet in #Ruby
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 hundr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string | Tokenize a string | Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks related to string operations:
Me... | #Prolog | Prolog | splitup(Sep,[token(B)|BL]) --> splitup(Sep,B,BL).
splitup(Sep,[A|AL],B) --> [A], {\+ [A] = Sep }, splitup(Sep,AL,B).
splitup(Sep,[],[B|BL]) --> Sep, splitup(Sep,B,BL).
splitup(_Sep,[],[]) --> [].
start :-
phrase(splitup(",",Tokens),"Hello,How,Are,You,Today"),
phrase(splitup(".",Tokens),Backtoget... | Give a code snippet in #Prolog
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X | Isqrt (integer square root) of X | Sometimes a function is needed to find the integer square root of X, where X can be a
real non─negative number.
Often X is actually a non─negative integer.
For the purposes of this task, X can be an integer or a real number, but if it
simplifies things in your computer programming language, assume... | #REXX | REXX | /*REXX program computes and displays the Isqrt (integer square root) of some integers.*/
numeric digits 200 /*insure 'nuff decimal digs for results*/
parse arg range power base . /*obtain optional arguments from the CL*/
if range=='' | range=="," then range= 0..65 ... | Give a code snippet in #REXX
Sometimes a function is needed to find the integer square root of X, where X can be a
real non─negative number.
Often X is actually a non─negative integer.
For the purposes of this task, X can be an integer or a real number, but if it
simplifies things in your computer ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pell%27s_equation | Pell's equation | Pell's equation (also called the Pell–Fermat equation) is a Diophantine equation of the form:
x2 - ny2 = 1
with integer solutions for x and y, where n is a given non-square positive integer.
Task requirements
find the smallest solution in positive integers to Pell's equation for... | #Prolog | Prolog |
% Find the square root as a continued fraction
cf_sqrt(N, Sz, [A0, Frac]) :-
A0 is floor(sqrt(N)),
(A0*A0 =:= N ->
Sz = 0, Frac = []
;
cf_sqrt(N, A0, A0, 0, 1, 0, [], Sz, Frac)).
cf_sqrt(N, A, A0, M0, D0, Sz0, L, Sz, R) :-
M1 is D0*A0 - M0,
D1 is (N - M1*M1) div D0,
A1 is (... | Give a code snippet in #Prolog
Pell's equation (also called the Pell–Fermat equation) is a Diophantine equation of the form:
x2 - ny2 = 1
with integer solutions for x and y, where n is a given non-square positive integer.
Task requirements
find the smallest solution in positive... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Forest_fire | Forest fire |
This page uses content from Wikipedia. The original article was at Forest-fire model. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Implement the Drossel and Schwabl definition of the fores... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <pthread.h>
#include <SDL.h>
// defaults
#define PROB_TREE 0.55
#define PROB_F 0.00001
#define PROB_P 0.001
#define TIMERFREQ 100
#ifndef WIDTH
# define WIDTH 640
#endif
#ifndef HEIGHT
# define HEIGHT ... | Give a code snippet in #C
This page uses content from Wikipedia. The original article was at Forest-fire model. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Implement the Drossel and Schw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #M4 | M4 | define(`V',`123')dnl
define(`VN',`-123')dnl
eval(V+1)
eval(VN+1) | Give a code snippet in #M4
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_intersection_of_a_line_with_a_plane | Find the intersection of a line with a plane | Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of (0, 0, 1) and which passes ... | #R | R | intersect_point <- function(ray_vec, ray_point, plane_normal, plane_point) {
pdiff <- ray_point - plane_point
prod1 <- pdiff %*% plane_normal
prod2 <- ray_vec %*% plane_normal
prod3 <- prod1 / prod2
point <- ray_point - ray_vec * as.numeric(prod3)
return(point)
} | Give a code snippet in #R
Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of (0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SOAP | SOAP | In this task, the goal is to create a SOAP client which accesses functions defined at http://example.com/soap/wsdl, and calls the functions soapFunc( ) and anotherSoapFunc( ).
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified... | #Julia | Julia | using LibCURL
function callSOAP(url, infilename, outfilename)
rfp = open(infilename, "r")
wfp = open(outfilename, "w+")
header = curl_slist_append(header, "Content-Type:text/xml")
header = curl_slist_append(header, "SOAPAction: rsc");
header = curl_slist_append(header, "Transfer-Encoding: chunke... | Give a code snippet in #Julia
In this task, the goal is to create a SOAP client which accesses functions defined at http://example.com/soap/wsdl, and calls the functions soapFunc( ) and anotherSoapFunc( ).
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect on... | 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... | #ALGOL_68 | ALGOL 68 | # -*- coding: utf-8 -*- #
CO REQUIRES:
MODE OBJVALUE = ~ # Mode/type of actual obj to be stacked #
END CO
MODE OBJNEXTLINK = STRUCT(
REF OBJNEXTLINK next,
OBJVALUE value # ... etc. required #
);
PROC obj nextlink new = REF OBJNEXTLINK:
HEAP OBJNEXTLINK;
PROC obj nextlink free = (REF OBJNEXTLINK free)VOID:... | Give a code snippet in #ALGOL_68
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... | 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... | #Haskell | Haskell | module Bitmap(module Bitmap) where
import Control.Monad
import Control.Monad.ST
import Data.Array.ST
newtype Pixel = Pixel (Int, Int) deriving Eq
instance Ord Pixel where
compare (Pixel (x1, y1)) (Pixel (x2, y2)) =
case compare y1 y2 of
EQ -> compare x1 x2
v -> v
instance Ix... | Give a code snippet in #Haskell
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 ... | 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... | #Arc | Arc | (point break
(while t
(let x (rand 20)
(prn "a: " x)
(if (is x 10)
(break)))
(prn "b: " (rand 20)))) | Give a code snippet in #Arc
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
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
... | #Wart | Wart | def (qsort (pivot ... ns))
(+ (qsort+keep (fn(_) (_ < pivot)) ns)
list.pivot
(qsort+keep (fn(_) (_ > pivot)) ns))
def (qsort x) :case x=nil
nil | Give a code snippet in #Wart
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 |
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