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/Display_a_linear_combination | Display a linear combination | Task
Display a finite linear combination in an infinite vector basis
(
e
1
,
e
2
,
…
)
{\displaystyle (e_{1},e_{2},\ldots )}
.
Write a function that, when given a finite list of scalars
(
α
1
,
α
2
,
…
)
{\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )}
,
creates a string representing t... | #Julia | Julia | # v0.6
linearcombination(coef::Array) = join(collect("$c * e($i)" for (i, c) in enumerate(coef) if c != 0), " + ")
for c in [[1, 2, 3], [0, 1, 2, 3], [1, 0, 3, 4], [1, 2, 0], [0, 0, 0], [0], [1, 1, 1],
[-1, -1, -1], [-1, -2, 0, -3], [-1]]
@printf("%20s -> %s\n", c, linearcombination(c))
end | Give a code snippet in #Julia
Task
Display a finite linear combination in an infinite vector basis
(
e
1
,
e
2
,
…
)
{\displaystyle (e_{1},e_{2},\ldots )}
.
Write a function that, when given a finite list of scalars
(
α
1
,
α
2
,
…
)
{\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )}
,
... | 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... | #BBC_BASIC | BBC BASIC | INSTALL @lib$+"STRINGLIB"
PRINT " Decimal Binary Gray Decoded"
FOR number% = 0 TO 31
gray% = FNgrayencode(number%)
PRINT number% " " FN_tobase(number%, 2, 5) ;
PRINT " " FN_tobase(gray%, 2, 5) FNgraydecode(gray%)
NEXT
END
DEF FNgrayenco... | Give a code snippet in #BBC_BASIC
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/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 ... | #Ada | Ada | with Ada.Text_IO; use Ada.Text_IO;
with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;
with Ada.Characters.Handling; use Ada.Characters.Handling;
procedure Soundex is
type UStrings is array(Natural range <>) of Unbounded_String;
function "+"(S:String) return Unbounded_String renames To_Unbounded_String;
f... | Give a code snippet in #Ada
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/Command-line_arguments | Command-line arguments | Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| #Amazing_Hopper | Amazing Hopper |
#defn main(_V_,_N_) #RAND, main:, V#RNDV=1,_V_={#VOID}, \
_N_=0,totalarg,mov(_N_), \
LOOPGETARG_#RNDV:, {[ V#RNDV ]},push(_V_),++V#RNDV,\
{_N_,V#RNDV},jle(LOOPGETARG_#RNDV),clear(V#RNDV)
| Give a code snippet in #Amazing_Hopper
Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/2 | Text processing/2 | The following task concerns data that came from a pollution monitoring station with twenty-four instruments monitoring twenty-four aspects of pollution in the air. Periodically a record is added to the file, each record being a line of 49 fields separated by white-space, which can be one or more space or tab characters... | #Erlang | Erlang |
-module( text_processing2 ).
-export( [task/0] ).
task() ->
Name = "priv/readings.txt",
try
File_contents = text_processing:file_contents( Name ),
[correct_field_format(X) || X<- File_contents],
{_Previous, Duplicates} = lists:foldl( fun date_duplicates/2, {"", []}, File_contents ),
io:fwrite( "Duplicates: ... | Give a code snippet in #Erlang
The following task concerns data that came from a pollution monitoring station with twenty-four instruments monitoring twenty-four aspects of pollution in the air. Periodically a record is added to the file, each record being a line of 49 fields separated by white-space, which can be one... | 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... | #C.2B.2B | C++ | #include <iostream>
#include <vector>
#include <utility>
std::vector<int> hailstone(int i)
{
std::vector<int> v;
while(true){
v.push_back(i);
if (1 == i) break;
i = (i % 2) ? (3 * i + 1) : (i / 2);
}
return v;
}
std::pair<int,int> find_longest_hailstone_seq(int n)
{
std... | Give a code snippet in #C.2B.2B
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) + ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Smalltalk | Smalltalk | Integer >> fibI
|aNMinus1 an t|
aNMinus1 := 1.
an := 0.
self timesRepeat:[
t := an.
an := an + aNMinus1 .
aNMinus1 := t.
].
^ an | Give a code snippet in #Smalltalk
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_inverse | Modular inverse | From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
{\displaystyle \exists k\in \math... | #Bracmat | Bracmat | ( ( mod-inv
= a b b0 x0 x1 q
. !arg:(?a.?b)
& ( !b:1
| (!b.0.1):(?b0.?x0.?x1)
& whl
' ( !a:>1
& div$(!a.!b):?q
& (!b.mod$(!a.!b)):(?a.?b)
& (!x1+-1*!q*!x0.!x0):(?x0.?x1)
)
& (!x:>0|!x1+!b0)
)
)
... | Give a code snippet in #Bracmat
From Wikipedia:
In modular arithmetic, the modular multiplicative inverse of an integer a modulo m is an integer x such that
a
x
≡
1
(
mod
m
)
.
{\displaystyle a\,x\equiv 1{\pmod {m}}.}
Or in other words, such that:
∃
k
∈
Z
,
a
x
=
1
+
k
m
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Pascal | Pascal | var
a, b: integer;
begin
readln(a, b);
writeln(a + b);
end. | Give a code snippet in #Pascal
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separat... | 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... | #EchoLisp | EchoLisp |
(lib 'math)
(mean '(1 2 3 4)) ;; mean of a list
→ 2.5
(mean #(1 2 3 4)) ;; mean of a vector
→ 2.5
(lib 'sequences)
(mean [1 3 .. 10]) ;; mean of a sequence
→ 5
;; error handling
(mean 'elvis)
⛔ error: mean : expected sequence : elvis
(mean ())
💣 error: mean : null is not an object
(mean #())
... | Give a code snippet in #EchoLisp
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 e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Boolean_values | Boolean values | Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| #COBOL | COBOL | 01 some-bool PIC 1 BIT. | Give a code snippet in #COBOL
Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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 ... | #PHP | PHP | <?php
echo soundex("Soundex"), "\n"; // S532
echo soundex("Example"), "\n"; // E251
echo soundex("Sownteks"), "\n"; // S532
echo soundex("Ekzampul"), "\n"; // E251
?> | Give a code snippet in #PHP
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/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), b... | #FutureBasic | FutureBasic | window 1
print date$
print date$("d MMM yyyy")
print date$("EEE, MMM d, yyyy")
print date$("MMMM d, yyyy ")
print date$("MMMM d, yyyy G")
print "This is day ";date$("D");" of the year"
print
print time$
print time$("hh:mm:ss")
print time$("h:mm a")
print time$("h:mm a zzz")
print
print time$("h:mm a ZZZZ "); date$("M... | Give a code snippet in #FutureBasic
Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Motzkin_numbers | Motzkin numbers | Definition
The nth Motzkin number (denoted by M[n]) is the number of different ways of drawing non-intersecting chords between n points on a circle (not necessarily touching every point by a chord).
By convention M[0] = 1.
Task
Compute and show on this page the first 42 Motzkin numbers or, if your language does not... | #Phix | Phix | with javascript_semantics
include mpfr.e
function motzkin(integer n)
sequence m = mpz_inits(2,1) -- {1,1}
mpz m2 = mpz_init() -- (scratch)
for i=3 to n do
mpz m1 = mpz_init() -- (a new mpz rqd for every m[i])
mpz_mul_si(m1,m[i-1],2*i-1) -- (nb i is 1-based)
mpz_mul_si... | Give a code snippet in #Phix
Definition
The nth Motzkin number (denoted by M[n]) is the number of different ways of drawing non-intersecting chords between n points on a circle (not necessarily touching every point by a chord).
By convention M[0] = 1.
Task
Compute and show on this page the first 42 Motzkin numbers... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix 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
... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program radixSort64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly */
.include "../includeConstantesAR... | Give a code snippet in #AArch64_Assembly
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #Vedit_macro_language | Vedit macro language | #10 = Get_Num("Enter number to search to: ", STATLINE)
Buf_Switch(Buf_Free) // Use edit buffer as flags array
Ins_Text("--") // 0 and 1 are not primes
Ins_Char('P', COUNT, #10-1) // init rest of the flags to "prime"
for (#1 = 2; #1*#1 < #10; #1++) {
Goto_Pos(#... | Give a code snippet in #Vedit_macro_language
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of E... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Shell_one-liner | Shell one-liner | Task
Show how to specify and execute a short program in the language from a command shell, where the input to the command shell is only one line in length.
Avoid depending on the particular shell or operating system used as much as is reasonable; if the language has notable implementations which have different comman... | #SNOBOL4 | SNOBOL4 | echo 'a output = "Hello, World!";end' | snobol4 -b | Give a code snippet in #SNOBOL4
Task
Show how to specify and execute a short program in the language from a command shell, where the input to the command shell is only one line in length.
Avoid depending on the particular shell or operating system used as much as is reasonable; if the language has notable implementa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_a_foreign-language_function | Call a foreign-language function | Task
Show how a foreign language function can be called from the language.
As an example, consider calling functions defined in the C language. Create a string containing "Hello World!" of the string type typical to the language. Pass the string content to C's strdup. The content can be copied if necessary. Get the... | #REXX | REXX | /*REXX program calls (invoke) a "foreign" (non-REXX) language routine/program. */
cmd = "MODE" /*define the command that is to be used*/
opts= 'CON: CP /status' /*define the options to be used for cmd*/
address 'SYSTEM' cmd opts ... | Give a code snippet in #REXX
Task
Show how a foreign language function can be called from the language.
As an example, consider calling functions defined in the C language. Create a string containing "Hello World!" of the string type typical to the language. Pass the string content to C's strdup. The content can b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #F.23 | F# | type DListAux<'T> = {mutable prev: DListAux<'T> option; data: 'T; mutable next: DListAux<'T> option}
type DList<'T> = {mutable front: DListAux<'T> option; mutable back: DListAux<'T> option} //'
let empty() = {front=None; back=None}
let addFront dlist elt =
match dlist.front with
| None ->
let e = Some {pr... | Give a code snippet in #F.23
Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abstract_type | Abstract type | Abstract type is a type without instances or without definition.
For example in object-oriented programming using some languages, abstract types can be partial implementations of other types, which are to be derived there-from. An abstract type may provide implementation of some operations and/or components. Abstract ... | #Vlang | Vlang | interface Beast {
kind() string
name() string
cry() string
}
struct Dog {
kind string
name string
}
fn (d Dog) kind() string { return d.kind }
fn (d Dog) name() string { return d.name }
fn (d Dog) cry() string { return "Woof" }
struct Cat {
kind string
name string
}
fn (c Cat) ki... | Give a code snippet in #Vlang
Abstract type is a type without instances or without definition.
For example in object-oriented programming using some languages, abstract types can be partial implementations of other types, which are to be derived there-from. An abstract type may provide implementation of some operatio... | 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... | #Visual_Prolog | Visual Prolog |
implement main
open core, std
domains
pythtrip = pt(integer, integer, integer).
class predicates
pythTrips : (integer) -> pythtrip nondeterm (i).
clauses
pythTrips(Limit) = pt(X,Y,Z) :-
X = fromTo(1,Limit),
Y = fromTo(X,Limit),
Z = fromTo(Y,Limit),
Z^2 = X^2 + Y^2... | Give a code snippet in #Visual_Prolog
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 loop... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Textonyms | Textonyms | When entering text on a phone's digital pad it is possible that a particular combination of digits corresponds to more than one word. Such are called textonyms.
Assuming the digit keys are mapped to letters as follows:
2 -> ABC
3 -> DEF
4 -> GHI
5 -> JKL
6 -> MNO
7 -> PQRS
8 -> TUV
9 -... | #Go | Go | package main
import (
"bufio"
"flag"
"fmt"
"io"
"log"
"os"
"strings"
"unicode"
)
func main() {
log.SetFlags(0)
log.SetPrefix("textonyms: ")
wordlist := flag.String("wordlist", "wordlist", "file containing the list of words to check")
flag.Parse()
if flag.NArg() != 0 {
flag.Usage()
os.Exit(2)
}
... | Give a code snippet in #Go
When entering text on a phone's digital pad it is possible that a particular combination of digits corresponds to more than one word. Such are called textonyms.
Assuming the digit keys are mapped to letters as follows:
2 -> ABC
3 -> DEF
4 -> GHI
5 -> JKL
6 -> MNO
7 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mode | Averages/Mode | Task[edit]
Write a program to find the mode value of a collection.
The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique.
If it is not appropriate or possible to support a general collection, use a vector (array), if possible. If it is not appropriat... | #Q | Q | mode:{(key x) where value x=max x} count each group @ | Give a code snippet in #Q
Task[edit]
Write a program to find the mode value of a collection.
The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique.
If it is not appropriate or possible to support a general collection, use a vector (array), if possib... | christopher/rosetta-code | |
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the... | #D | D | import std.conv;
import std.stdio;
immutable CHARS = ["A","ö","Ж","€","𝄞"];
void main() {
writeln("Character Code-Point Code-Units");
foreach (c; CHARS) {
auto bytes = cast(ubyte[]) c; //The raw bytes of a character can be accessed by casting
auto unicode = cast(uint) to!dstring(c)[0]; ... | Give a code snippet in #D
As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes represe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cut_a_rectangle | Cut a rectangle | A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles... | #Perl | Perl | use strict;
use warnings;
my @grid = 0;
my ($w, $h, $len);
my $cnt = 0;
my @next;
my @dir = ([0, -1], [-1, 0], [0, 1], [1, 0]);
sub walk {
my ($y, $x) = @_;
if (!$y || $y == $h || !$x || $x == $w) {
$cnt += 2;
return;
}
my $t = $y * ($w + 1) + $x;
$grid[$_]++ for $t, $len - $t;
for... | Give a code snippet in #Perl
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths ... | 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... | #Ada | Ada | with Ada.Text_IO;
procedure Remove_Characters is
S: String := "upraisers";
use Ada.Text_IO;
begin
Put_Line("Full String: """ & S & """");
Put_Line("Without_First: """ & S(S'First+1 .. S'Last) & """");
Put_Line("Without_Last: """ & S(S'First .. S'Last-1) & """");
Put_Line("Without_Both: """ & S... | Give a code snippet in #Ada
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_squares_of_odd_order | Magic squares of odd order | A magic square is an NxN square matrix whose numbers (usually integers) consist of consecutive numbers arranged so that the sum of each row and column, and both long (main) diagonals are equal to the same sum (which is called the magic number or magic constant).
The numbers are usually (but not always) t... | #Visual_Basic | Visual Basic | Sub magicsquare()
'Magic squares of odd order
Const n = 9
Dim i As Integer, j As Integer, v As Integer
Debug.Print "The square order is: " & n
For i = 1 To n
For j = 1 To n
v = ((i * 2 - j + n - 1) Mod n) * n + ((i * 2 + j - 2) Mod n) + 1
Debug.Print Right(Space(5) & ... | Give a code snippet in #Visual_Basic
A magic square is an NxN square matrix whose numbers (usually integers) consist of consecutive numbers arranged so that the sum of each row and column, and both long (main) diagonals are equal to the same sum (which is called the magic number or magic constant).
The ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/While | Loops/While | Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For... | #ALGOL-M | ALGOL-M | begin
integer i;
i := 1024;
while i > 0 do begin
write( i );
i := i / 2;
end;
end | Give a code snippet in #ALGOL-M
Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downw... | 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
... | #BCPL | BCPL | get "libhdr"
let max(A, len) = valof
$( let x = 0
for i=0 to len-1
if x<A!i do x := A!i
resultis x
$)
let beadsort(A, len) be
$( let size = max(A, len)
let tvec = getvec(size-1)
for i=0 to size-1 do tvec!i := 0
for i=0 to len-1
for j=0 to A!i-1 do tvec!j := tvec!j + 1
for i... | Give a code snippet in #BCPL
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #REXX | REXX | /*REXX program performs a radix sort on an integer array (can be negative/zero/positive)*/
call gen /*call subroutine to generate numbers. */
call radSort n, w /*invoke the radix sort subroutine. */
call show ... | Give a code snippet in #REXX
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #BASIC | BASIC | DATA 6
DATA "Given$a$text$file$of$many$lines,$where$fields$within$a$line$"
DATA "are$delineated$by$a$single$'dollar'$character,$write$a$program"
DATA "that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$"
DATA "column$are$separated$by$at$least$one$space."
DATA "Further,$... | Give a code snippet in #BASIC
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 lef... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parallel_calculations | Parallel calculations | Many programming languages allow you to specify computations to be run in parallel.
While Concurrent computing is focused on concurrency,
the purpose of this task is to distribute time-consuming calculations
on as many CPUs as possible.
Assume we have a collection of numbers, and want to find the one
with the largest ... | #Julia | Julia |
using Primes
factortodict(d, n) = (d[minimum(collect(keys(factor(n))))] = n)
# Numbers are from from the Raku example.
numbers = [64921987050997300559, 70251412046988563035, 71774104902986066597,
83448083465633593921, 84209429893632345702, 87001033462961102237,
87762379890959854011, 895... | Give a code snippet in #Julia
Many programming languages allow you to specify computations to be run in parallel.
While Concurrent computing is focused on concurrency,
the purpose of this task is to distribute time-consuming calculations
on as many CPUs as possible.
Assume we have a collection of numbers, and want to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Case-sensitivity_of_identifiers | Case-sensitivity of identifiers | Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, Samba and Bernie.
For a language... | #Oforth | Oforth | : threeDogs
| dog Dog DOG |
"Benjamin" ->dog
"Samba" ->Dog
"Bernie" ->DOG
System.Out "The three dogs are named " << dog << ", " << Dog << " and " << DOG << "." << cr ; | Give a code snippet in #Oforth
Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, S... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Time_a_function | Time a function | Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
between start and finish, which could ... | #PureBasic | PureBasic | Procedure Foo(Limit)
Protected i, palindromic, String$
For i=0 To Limit
String$=Str(i)
If String$=ReverseString(String$)
palindromic+1
EndIf
Next
ProcedureReturn palindromic
EndProcedure
If OpenConsole()
Define Start, Stop, cnt
PrintN("Starting timing of a calculation,")
PrintN("for th... | Give a code snippet in #PureBasic
Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
bet... | 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... | #Dyalect | Dyalect | String.Repeat("ha", 5) | Give a code snippet in #Dyalect
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/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | Empty[a_] := If[Length[a] == 0, True, False]
SetAttributes[Push, HoldAll]; Push[a_, elem_] := AppendTo[a, elem]
SetAttributes[Pop, HoldAllComplete]; Pop[a_] := If[EmptyQ[a], False, b = First[a]; Set[a, Most[a]]; b]
Queue = {}
-> {}
Empty[Queue]
-> True
Push[Queue, "1"]
-> {"1"}
EmptyQ[Queue]
->False
Pop[Queue]
->1
Po... | Give a code snippet in #Mathematica.2FWolfram_Language
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(F... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_puzzle | Sum and product puzzle | Task[edit]
Solve the "Impossible Puzzle":
X and Y are two different whole numbers greater than 1. Their sum is no greater than 100, and Y is greater than X. S and P are two mathematicians (and consequently perfect logicians); S knows the sum X+Y and P knows the product X*Y. Both S and P know all the information in th... | #Factor | Factor | USING: combinators.short-circuit fry kernel literals math
math.ranges memoize prettyprint sequences sets tools.time ;
IN: rosetta-code.sum-and-product
CONSTANT: s1 $[
2 100 [a,b] dup cartesian-product concat
[ first2 { [ < ] [ + 100 < ] } 2&& ] filter
]
: quot-eq ( pair quot -- seq )
[ s1 ] 2dip tuck '[... | Give a code snippet in #Factor
Task[edit]
Solve the "Impossible Puzzle":
X and Y are two different whole numbers greater than 1. Their sum is no greater than 100, and Y is greater than X. S and P are two mathematicians (and consequently perfect logicians); S knows the sum X+Y and P knows the product X*Y. Both S and ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #VAX_Assembly | VAX Assembly |
desc: .ascid "Hello World!" ;descriptor (len+addr) and text
.entry hello, ^m<> ;register save mask
pushaq desc ;address of descriptor
calls #1, g^lib$put_output ;call with one argument on stack
ret ;restore registers, clean stack & return... | Give a code snippet in #VAX_Assembly
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #ALGOL_68 | ALGOL 68 | PROC copy file v1 = (STRING in name, out name)VOID: (
# note: algol68toc-1.18 - can compile, but not run v1 #
INT errno;
FILE in file, out file;
errno := open(in file, in name, stand in channel);
errno := open(out file, out name, stand out channel);
BOOL in ended := FALSE;
PROC call back ended = (REF... | Give a code snippet in #ALGOL_68
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a fil... | 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
... | #Haskell | Haskell | {-# LANGUAGE NumericUnderscores #-}
import Control.Monad (guard)
import Math.NumberTheory.Primes.Testing (isPrime)
import Data.List.Split (chunksOf)
import Data.List (intercalate)
import Text.Printf (printf)
smarandache :: [Integer]
smarandache = [2,3,5,7] <> s [2,3,5,7] >>= \x -> guard (isPrime x) >> [x]
where s xs... | Give a code snippet in #Haskell
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 hu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Factor | Factor | USING: continuations fry io io.encodings.utf8 io.files kernel
math ;
IN: rosetta-code.nth-line
: nth-line ( path encoding n -- str/f )
[ f ] 3dip '[
[ _ [ drop readln [ return ] unless* ] times ]
with-return
] with-file-reader ;
: nth-line-demo ( -- )
"input.txt" utf8 7 nth-line [ "line ... | Give a code snippet in #Factor
Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #NetRexx | NetRexx | /*NetRexx *************************************************************
* program to sum the squares of a vector of fifteen numbers.
* translated from REXX
* 14.05.2013 Walter Pachl
**********************************************************************/
numeric digits 50 /*allow 50-digit # (default is... | Give a code snippet in #NetRexx
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Kite | Kite | "#!/usr/local/bin/kite
"Hello world!"|print; | Give a code snippet in #Kite
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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
| #Nim | Nim | type
Point = object
x, y: float
Circle = object
center: Point
radius: float
# Constructors
proc createPoint(x, y = 0.0): Point =
result.x = x
result.y = y
proc createCircle(x, y = 0.0, radius = 1.0): Circle =
result.center.x = x
result.center.y = y
result.radius = radius
var p1 = creat... | Give a code snippet in #Nim
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/Diversity_prediction_theorem | Diversity prediction theorem | The wisdom of the crowd is the collective opinion of a group of individuals rather than that of a single expert.
Wisdom-of-the-crowds research routinely attributes the superiority of crowd averages over individual judgments to the elimination of individual noise, an explanation that assumes independence of the i... | #REXX | REXX | /* REXX */
Numeric Digits 20
Call diversityTheorem 49,'48 47 51'
Say '--------------------------------------'
Call diversityTheorem 49,'48 47 51 42'
Exit
diversityTheorem:
Parse Arg truth,list
average=average(list)
Say 'average-error='averageSquareDiff(truth,list)
Say 'crowd-error='||(truth-average)**2
Say ... | Give a code snippet in #REXX
The wisdom of the crowd is the collective opinion of a group of individuals rather than that of a single expert.
Wisdom-of-the-crowds research routinely attributes the superiority of crowd averages over individual judgments to the elimination of individual noise, an explanation that... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/Shunting-yard_algorithm | Parsing/Shunting-yard algorithm | Task
Given the operator characteristics and input from the Shunting-yard algorithm page and tables, use the algorithm to show the changes in the operator stack and RPN output
as each individual token is processed.
Assume an input of a correct, space separated, string of tokens representing an infix expression
Gener... | #Icon_and_Unicon | Icon and Unicon | procedure main()
infix := "3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3"
printf("Infix = %i\n",infix)
printf("RPN = %i\n",Infix2RPN(infix))
end
link printf
record op_info(pr,as) # p=precedence, a=associativity (left=null)
procedure Infix2RPN(expr) #: Infix to RPN parser - shunting yard
stati... | Give a code snippet in #Icon_and_Unicon
Task
Given the operator characteristics and input from the Shunting-yard algorithm page and tables, use the algorithm to show the changes in the operator stack and RPN output
as each individual token is processed.
Assume an input of a correct, space separated, string of token... | 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... | #Raku | Raku | use Test;
my $a = set <a b c>;
my $b = set <b c d>;
my $c = set <a b c d e>;
ok 'c' ∈ $a, "c is an element in set A";
nok 'd' ∈ $a, "d is not an element in set A";
is-deeply $a ∪ $b, set(<a b c d>), "union; a set of all elements either in set A or in set B";
is-deeply $a ∩ $b, set(<b c>), "intersection; a set of ... | Give a code snippet in #Raku
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 cr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catmull%E2%80%93Clark_subdivision_surface | Catmull–Clark subdivision surface | Implement the Catmull-Clark surface subdivision (description on Wikipedia), which is an algorithm that maps from a surface (described as a set of points and a set of polygons with vertices at those points) to another more refined surface. The resulting surface will always consist of a mesh of quadrilaterals.
The proce... | #J | J | avg=: +/ % #
havePoints=: e."1/~ i.@#
catmullclark=:3 :0
'mesh points'=. y
face_point=. avg"2 mesh{points
point_face=. |: mesh havePoints points
avg_face_points=. point_face avg@#"1 2 face_point
edges=. ~.,/ meshEdges=. mesh /:~@,"+1|."1 mesh
edge_face=. *./"2 edges e."0 1/ mesh
edge_center=. avg"2 ed... | Give a code snippet in #J
Implement the Catmull-Clark surface subdivision (description on Wikipedia), which is an algorithm that maps from a surface (described as a set of points and a set of polygons with vertices at those points) to another more refined surface. The resulting surface will always consist of a mesh of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evolutionary_algorithm | Evolutionary algorithm | Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its argument to the target string.... | #ALGOL_68 | ALGOL 68 | STRING target := "METHINKS IT IS LIKE A WEASEL";
PROC fitness = (STRING tstrg)REAL:
(
INT sum := 0;
FOR i FROM LWB tstrg TO UPB tstrg DO
sum +:= ABS(ABS target[i] - ABS tstrg[i])
OD;
# fitness := # 100.0*exp(-sum/10.0)
);
PROC rand char = CHAR:
(
#STATIC# []CHAR ucchars = "ABCDEFGHIJKLMNOPQRSTU... | Give a code snippet in #ALGOL_68
Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nested_function | Nested function | In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two nested functions that prints t... | #Pascal | Pascal | sub makeList {
my $separator = shift;
my $counter = 1;
sub makeItem { $counter++ . $separator . shift . "\n" }
makeItem("first") . makeItem("second") . makeItem("third")
}
print makeList(". "); | Give a code snippet in #Pascal
In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of tw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extensible_prime_generator | Extensible prime generator | Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi... | #Zig | Zig |
const std = @import("std");
const builtin = std.builtin;
const heap = std.heap;
const mem = std.mem;
const meta = std.meta;
fn assertInt(comptime T: type) builtin.TypeInfo.Int {
if (@typeInfo(T) != .Int)
@compileError("data type must be an integer.");
const int = @typeInfo(T).Int;
if (int.is_sig... | Give a code snippet in #Zig
Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or progra... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Problem_of_Apollonius | Problem of Apollonius |
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty straightforward.
The solutions to the ... | #AutoHotkey | AutoHotkey | #NoEnv
#SingleInstance, Force
SetBatchLines, -1
; Uncomment if Gdip.ahk is not in your standard library
;#Include, Gdip.ahk
; Start gdi+
If !pToken := Gdip_Startup()
{
MsgBox, 48, gdiplus error!, Gdiplus failed to start. Please ensure you have gdiplus on your system
ExitApp
}
OnExit, Exit
; I've added a simple ne... | Give a code snippet in #AutoHotkey
Task
Implement a solution to the Problem of Apollonius (description on Wikipedia) which is the problem of finding the circle that is tangent to three specified circles (colored black in the diagram below to the right).
There is an algebraic solution which is pretty strai... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Shoelace_formula_for_polygonal_area | Shoelace formula for polygonal area | Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns the absolute value)
Task
Write ... | #Lambdatalk | Lambdatalk |
{def shoelace
{lambda {:pol}
{abs
{/
{-
{+ {S.map {{lambda {:pol :i} {* {car {A.get :i :pol}}
{cdr {A.get {+ :i 1} :pol}}}} :pol}
{S.serie 0 {- {A.length :pol} 2}}}
{* {car {A.get {- {A.length :pol} 1} :pol}}
... | Give a code snippet in #Lambdatalk
Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs retur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Neko | Neko | /**
Detect division by zero
*/
var ans = 1.0 / 0.0
if $isinfinite(ans) $print("division by zero: ", ans, "\n")
ans = 1 / 0
if $isinfinite(ans) $print("division by zero: ", ans, "\n")
try $print($idiv(1, 0)) catch problem $print("idiv by zero: ", problem, "\n") | Give a code snippet in #Neko
Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Racket | Racket | #lang racket/base
;;;; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
;;;; Derived from 'D' Implementation
;;;; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
(require racket/date racket/match)
(define seasons '(Chao... | Give a code snippet in #Racket
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newline_omission | Hello world/Newline omission | Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standard error
Hello world/Text
| #Processing | Processing |
print("Goodbye, World!"); /* No automatic newline */
| Give a code snippet in #Processing
Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Benford%27s_law | Benford's law |
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-digit law, refers to the freque... | #Run_BASIC | Run BASIC |
N = 1000
for i = 0 to N - 1
n$ = str$(fibonacci(i))
j = val(left$(n$,1))
actual(j) = actual(j) +1
next
print
html "<table border=1><TR bgcolor=wheat><TD>Digit<td>Actual<td>Expected</td><tr>"
for i = 1 to 9
html "<tr align=right><td>";i;"</td><td>";using("##.###",actual(i)/10);"</td><td>";using("##.###"... | Give a code snippet in #Run_BASIC
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the fi... | 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
| #Raku | Raku | use Prime::Factor:ver<0.3.0+>;
use Lingua::EN::Numbers;
say "\nTau function - first 100:\n", # ID
(1..*).map({ +.&divisors })[^100]\ # the task
.batch(20)».fmt("%3d").join("\n"); # display formatting
say "\nTau numbers - first 100:\n", # ID
(1..*).grep({ $_ %% +.&divisors })[^100]\ ... | Give a code snippet in #Raku
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/Anti-primes | Anti-primes | The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| #Racket | Racket | #lang racket
(require racket/generator
math/number-theory)
(define (get-divisors n)
(apply * (map (λ (factor) (add1 (second factor))) (factorize n))))
(define antiprimes
(in-generator
(for/fold ([prev 0]) ([i (in-naturals 1)])
(define divisors (get-divisors i))
(when (> divisors prev) (y... | Give a code snippet in #Racket
The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| 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... | #PHP | PHP | <?php
function symbolTable() {
$symbol = array();
for ($c = ord('a') ; $c <= ord('z') ; $c++) {
$symbol[$c - ord('a')] = chr($c);
}
return $symbol;
}
function mtfEncode($original, $symbol) {
$encoded = array();
for ($i = 0 ; $i < strlen($original) ; $i++) {
$char = $original[... | Give a code snippet in #PHP
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 i... | 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.
| #8th | 8th |
7.125 "%09.3f" s:strfmt
. cr
| Give a code snippet in #8th
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/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 ... | #Python | Python | import sys
print >> sys.stderr, "Goodbye, World!" | Give a code snippet in #Python
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/Kaprekar_numbers | Kaprekar numbers | A positive integer is a Kaprekar number if:
It is 1 (unity)
The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number.
Note that a split resulting in a part consisting purely of 0s is not valid,
as 0 is not considered positive.
... | #CLU | CLU | % This program assumes a 64-bit system.
% On a 32-bit system, the main task (show Kaprekar numbers < 10,000)
% will run correctly, but the extra credit part will crash with
% an overflow exception.
% Yield all positive splits of a number
splits = iter (n, base: int) yields (int,int)
step: int := base
while n ... | Give a code snippet in #CLU
A positive integer is a Kaprekar number if:
It is 1 (unity)
The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number.
Note that a split resulting in a part consisting purely of 0s is not valid,
as 0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zig-zag_matrix | Zig-zag matrix | Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to encode images).
For example, gi... | #Lasso | Lasso |
var(
'square' = array
,'size' = integer( 5 )// for a 5 X 5 square
,'row' = array
,'x' = integer( 1 )
,'y' = integer( 1 )
,'counter' = integer( 1 )
);
// create place-holder matrix
loop( $size );
$row = array;
loop( $size );
$row->insert( 0 );
/loop;
... | Give a code snippet in #Lasso
Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to enc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Best_shuffle | Best shuffle | Task
Shuffle the characters of a string in such a way that as many of the character values are in a different position as possible.
A shuffle that produces a randomized result among the best choices is to be preferred. A deterministic approach that produces the same sequence every time is acceptable as an alternative... | #D | D | import std.stdio, std.random, std.algorithm, std.conv, std.range,
std.traits, std.typecons;
auto bestShuffle(S)(in S orig) @safe if (isSomeString!S) {
static if (isNarrowString!S)
immutable o = orig.dtext;
else
alias o = orig;
auto s = o.dup;
s.randomShuffle;
foreach (im... | Give a code snippet in #D
Task
Shuffle the characters of a string in such a way that as many of the character values are in a different position as possible.
A shuffle that produces a randomized result among the best choices is to be preferred. A deterministic approach that produces the same sequence every time is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Heronian_triangles | Heronian triangles | Hero's formula for the area of a triangle given the length of its three sides a, b, and c is given by:
A
=
s
(
s
−
a
)
(
s
−
b
)
(
s
−
c
)
,
{\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},}
where s is half the perimeter of the triangle; that is,
s
=
a
+
b
+
c
2
.
{\displaystyle s... | #Rust | Rust |
use num_integer::Integer;
use std::{f64, usize};
const MAXSIZE: usize = 200;
#[derive(Debug)]
struct HerionanTriangle {
a: usize,
b: usize,
c: usize,
area: usize,
perimeter: usize,
}
fn get_area(a: &usize, b: &usize, c: &usize) -> f64 {
let s = (a + b + c) as f64 / 2.;
(s * (s - *a a... | Give a code snippet in #Rust
Hero's formula for the area of a triangle given the length of its three sides a, b, and c is given by:
A
=
s
(
s
−
a
)
(
s
−
b
)
(
s
−
c
)
,
{\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},}
where s is half the perimeter of the triangle; that is,
s
=
a
+
b... | 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... | #OCaml | OCaml | #load "str.cma"
open Str
let input = "\
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$to$... | Give a code snippet in #OCaml
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 lef... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Smallest_number_k_such_that_k%2B2%5Em_is_composite_for_all_m_less_than_k | Smallest number k such that k+2^m is composite for all m less than k | Generate the sequence of numbers a(k), where each k is the smallest positive integer such that k + 2m is composite for every positive integer m less than k.
For example
Suppose k == 7; test m == 1 through m == 6. If any are prime, the test fails.
Is 7 + 21 (9) prime? False
Is 7 + 22 (11) prime? True
So 7 is not a... | #Perl | Perl | use strict;
use warnings;
use bigint;
use ntheory 'is_prime';
my $cnt;
LOOP: for my $k (2..1e10) {
next unless 1 == $k % 2;
for my $m (1..$k-1) {
next LOOP if is_prime $k + (1<<$m)
}
print "$k ";
last if ++$cnt == 5;
} | Give a code snippet in #Perl
Generate the sequence of numbers a(k), where each k is the smallest positive integer such that k + 2m is composite for every positive integer m less than k.
For example
Suppose k == 7; test m == 1 through m == 6. If any are prime, the test fails.
Is 7 + 21 (9) prime? False
Is 7 + 22 (... | 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.)
| #Ruby | Ruby | x = "code" # I am a comment
=begin hello
I a POD documentation comment like Perl
=end puts "code" | Give a code snippet in #Ruby
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/Chat_server | Chat server | Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
| #Groovy | Groovy | class ChatServer implements Runnable {
private int port = 0
private List<Client> clientList = new ArrayList<>()
ChatServer(int port) {
this.port = port
}
@SuppressWarnings("GroovyInfiniteLoopStatement")
@Override
void run() {
try {
ServerSocket serverSocket = ... | Give a code snippet in #Groovy
Task
Write a server for a minimal text based chat.
People should be able to connect via ‘telnet’, sign on with a nickname, and type messages which will then be seen by all other connected users. Arrivals and departures of chat members should generate appropriate notification messages.
... | 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
| #Amazing_Hopper | Amazing Hopper |
#!/usr/bin/hopper
#include <hopper.h>
main:
/* execute "ls -lstar" with no result return (only displayed) */
{"ls -lstar"},execv
/* this form does not allow composition of the line with variables.
Save result in the variable "s", and then display it */
s=`ls -l | awk '{if($2=="2")print $0;}'`
{... | Give a code snippet in #Amazing_Hopper
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/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.
| #Arturo | Arturo | nthRoot: function [a,n][
N: to :floating n
result: a
x: a / N
while [0.000000000000001 < abs result-x][
x: result
result: (1//n) * add (n-1)*x a/pow x n-1
]
return result
]
print nthRoot 34.0 5
print nthRoot 42.0 10
print nthRoot 5.0 2 | Give a code snippet in #Arturo
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/Strip_comments_from_a_string | Strip comments from a string | Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whitespace debacle: There is s... | #Sidef | Sidef | func strip_comment(s) {
(s - %r'[#;].*').strip;
}
[" apples, pears # and bananas",
" apples, pears ; and bananas",
" apples, pears "].each { |s|
say strip_comment(s).dump;
}; | Give a code snippet in #Sidef
Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
W... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_frequency | Function frequency | Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred).
This is a static analysis: The question is not how often each function is
actually executed at runtime, but how often it is used by... | #Tcl | Tcl | package require Tcl 8.6
proc examine {filename} {
global cmds
set RE "(?:^|\[\[\{\])\[\\w:.\]+"
set f [open $filename]
while {[gets $f line] >= 0} {
set line [string trim $line]
if {$line eq "" || [string match "#*" $line]} {
continue
}
foreach cmd [regexp -all -inline $RE $line] {
incr ... | Give a code snippet in #Tcl
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred).
This is a static analysis: The question is not how often each function is
actually executed at runtime... | 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 ...... | #Nanoquery | Nanoquery | q = 1; r = 0; t = 1
k = 1; n = 3; l = 3
nn = null; nr = null
first = true
while true
if (((4 * q) + r) - t) < (n * t)
print n
if first
print "."
first = false
end
nr = int(10 * (r - (n * t)))
n = int((10 * ((3 * q) + r)) / t) - (10 * n)
q *= 10
r = nr
else
nr = int(((2 * q) + r) * l)
nn = ... | Give a code snippet in #Nanoquery
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Numerical_integration/Gauss-Legendre_Quadrature | Numerical integration/Gauss-Legendre Quadrature |
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function
W
(
x
)
{\displaystyle ... | #MATLAB | MATLAB |
%Print the result.
disp(GLGD_int(@(x) exp(x), -3, 3, 5));
%Integration using Gauss-Legendre quad
%Does almost the same as 'integral' in MATLAB
function y=GLGD_int(fun,xmin,xmax,n)
%fun: the intergrand as a function handle
%xmin: lower boundary of integration
%xmax: upper boundary of integration
%n: order of polynom... | Give a code snippet in #MATLAB
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting functi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/15_puzzle_game | 15 puzzle game |
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| #Perl | Perl |
use strict;
use warnings;
use Getopt::Long;
use List::Util 1.29 qw(shuffle pairmap first all);
use Tk;
# 5 options 1 label text
my ($verbose,@fixed,$nocolor,$charsize,$extreme,$solvability);
unless (GetOptions (
'verbose!' => \$verbose,
... | Give a code snippet in #Perl
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_octal | Count in octal | Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
Related task
Integer sequ... | #Ada | Ada | with Ada.Text_IO;
procedure Octal is
package IIO is new Ada.Text_IO.Integer_IO(Integer);
begin
for I in 0 .. Integer'Last loop
IIO.Put(I, Base => 8);
Ada.Text_IO.New_Line;
end loop;
end Octal; | Give a code snippet in #Ada
Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #JavaScript | JavaScript | document.write("Hello world!"); | Give a code snippet in #JavaScript
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard er... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Append_a_record_to_the_end_of_a_text_file | Append a record to the end of a text file | Many systems offer the ability to open a file for writing, such that any data written will be appended to the end of the file. Further, the file operations will always adjust the position pointer to guarantee the end of the file, even in a multitasking environment.
This feature is most useful in the case of log files,... | #Nim | Nim | import posix
import strutils
type
# GECOS representation.
Gecos = tuple[fullname, office, extension, homephone, email: string]
# Record representation.
Record = object
account: string
password: string
uid: int
gid: int
gecos: Gecos
directory: string
shell: string
#-----------... | Give a code snippet in #Nim
Many systems offer the ability to open a file for writing, such that any data written will be appended to the end of the file. Further, the file operations will always adjust the position pointer to guarantee the end of the file, even in a multitasking environment.
This feature is most use... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #SSEM | SSEM |
// variable declaration
var table, chair;
// assignment
var table = 10, chair = -10;
// multiple assignment to the same value
table = chair = 0;
// multiple assignment to an array
(
var table, chair;
#table, chair = [10, -10];
#table ... chair = [10, -10, 2, 3]; // with ellipsis: now chair is [-10, 2, 3]
)
//... | Give a code snippet in #SSEM
Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_increasing_subsequence | Longest increasing subsequence | Calculate and show here a longest increasing subsequence of the list:
{
3
,
2
,
6
,
4
,
5
,
1
}
{\displaystyle \{3,2,6,4,5,1\}}
And of the list:
{
0
,
8
,
4
,
12
,
2
,
10
,
6
,
14
,
1
,
9
,
5
,
13
,
3
,
11
,
7
,
15
}
{\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}}
Note that a list may have m... | #Sidef | Sidef | func lis(a) {
var l = a.len.of { [] }
l[0] << a[0]
for i in (1..a.end) {
for j in ^i {
if ((a[j] < a[i]) && (l[i].len < l[j].len+1)) {
l[i] = [l[j]...]
}
}
l[i] << a[i]
}
l.max_by { .len }
}
say lis(%i<3 2 6 4 5 1>)
say lis(%i<0 8 4 1... | Give a code snippet in #Sidef
Calculate and show here a longest increasing subsequence of the list:
{
3
,
2
,
6
,
4
,
5
,
1
}
{\displaystyle \{3,2,6,4,5,1\}}
And of the list:
{
0
,
8
,
4
,
12
,
2
,
10
,
6
,
14
,
1
,
9
,
5
,
13
,
3
,
11
,
7
,
15
}
{\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Man_or_boy_test | Man or boy test | Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of the test was to distinguis... | #C.23 | C# | using System;
delegate T Func<T>();
class ManOrBoy
{
static void Main()
{
Console.WriteLine(A(10, C(1), C(-1), C(-1), C(1), C(0)));
}
static Func<int> C(int i)
{
return delegate { return i; };
}
static int A(int k, Func<int> x1, Func<int> x2, Func<int> x3, Func<int> x... | Give a code snippet in #C.23
Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback | Guess the number/With feedback | Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
higher than the target,
equal to... | #Brat | Brat | number = random 10
p "Guess a number between 1 and 10."
until {
guess = ask("Guess: ").to_i
true? (guess.null? || { guess > 10 || guess < 1 })
{ p "Please guess a number between 1 and 10."}
{ true? guess == number
{ p "Correct!"; true }
{ true? guess < number
{ p "Too low!" }
... | Give a code snippet in #Brat
Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
hig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tic-tac-toe | Tic-tac-toe |
Task
Play a game of tic-tac-toe.
Ensure that legal moves are played and that a winning position is notified.
Tic-tac-toe is also known as:
naughts and crosses
tic tac toe
tick tack toe
three in a row
tres en rayo and
Xs and Os
See also
MathWorld™, Tic-Tac-Toe game.
Wikipedi... | #ALGOL_W | ALGOL W | begin
string(10) board;
% initialise the board %
procedure initBoard ; board := " 123456789";
% display the board %
procedure showBoard ;
begin
s_w := 0;
write... | Give a code snippet in #ALGOL_W
Task
Play a game of tic-tac-toe.
Ensure that legal moves are played and that a winning position is notified.
Tic-tac-toe is also known as:
naughts and crosses
tic tac toe
tick tack toe
three in a row
tres en rayo and
Xs and Os
See also
MathWorl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Clear_the_screen | Terminal control/Clear the screen | Task
Clear the terminal window.
| #Wren | Wren | System.print("\e[2J") | Give a code snippet in #Wren
Task
Clear the terminal window.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to rais... | #Kotlin | Kotlin | // version 1.0.6
class U0 : Throwable("U0 occurred")
class U1 : Throwable("U1 occurred")
fun foo() {
for (i in 1..2) {
try {
bar(i)
} catch(e: U0) {
println(e.message)
}
}
}
fun bar(i: Int) {
baz(i)
}
fun baz(i: Int) {
when (i) {
1 -> throw... | Give a code snippet in #Kotlin
Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arra... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
... | #Lhogho | Lhogho | make "Void "V0
make "Long "U4
make "kernel32_handle libload "kernel32.dll
to Sleep :dwMilliseconds
end
external "Sleep [ Void Sleep Long] :kernel32_handle
to millisleep :n
print [Sleeping...]
Sleep :n ; units: 1/1000th of a second
print [Awake.]
end | Give a code snippet in #Lhogho
Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main threa... | 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... | #BaCon | BaCon | ' Variadic functions
OPTION BASE 1
SUB demo (VAR arg$ SIZE argc)
LOCAL x
PRINT "Amount of incoming arguments: ", argc
FOR x = 1 TO argc
PRINT arg$[x]
NEXT
END SUB
' No argument
demo(0)
' One argument
demo("abc")
' Three arguments
demo("123", "456", "789") | Give a code snippet in #BaCon
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.
R... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this wil... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | RowReduce[{{1, 2, -1, -4}, {2, 3, -1, -11}, {-2, 0, -3, 22}}] | Give a code snippet in #Mathematica.2FWolfram_Language
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Playing_cards | Playing cards | Task
Create a data structure and the associated methods to define and manipulate a deck of playing cards.
The deck should contain 52 unique cards.
The methods must include the ability to:
make a new deck
shuffle (randomize) the deck
deal from the deck
print the current contents of a deck
Each card mu... | #ALGOL_68 | ALGOL 68 | MODE CARD = STRUCT(STRING pip, suit); # instance attributes #
# class members & attributes #
STRUCT(
PROC(REF CARD, STRING, STRING)VOID init,
FORMAT format,
PROC(REF CARD)STRING repr,
[]STRING suits, pips
) class card = (
# PROC init = # (REF CARD self, STRING pip, suit)VOID:(
pip OF self:=pip;
suit ... | Give a code snippet in #ALGOL_68
Task
Create a data structure and the associated methods to define and manipulate a deck of playing cards.
The deck should contain 52 unique cards.
The methods must include the ability to:
make a new deck
shuffle (randomize) the deck
deal from the deck
print the curren... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pentagram | Pentagram |
A pentagram is a star polygon, consisting of a central pentagon of which each side forms the base of an isosceles triangle. The vertex of each triangle, a point of the star, is 36 degrees.
Task
Draw (or print) a regular pentagram, in any orientation. Use a different color (or token) for stroke and fill, and backg... | #IS-BASIC | IS-BASIC | 100 PROGRAM "Pentagra.bas"
110 OPTION ANGLE DEGREES
120 GRAPHICS HIRES 4
130 SET PALETTE BLUE,CYAN,YELLOW,BLACK
140 PLOT 640,700,ANGLE 288;
150 FOR I=1 TO 5
160 PLOT FORWARD 700,RIGHT 144;
170 NEXT
180 SET INK 3
190 SET BEAM OFF:PLOT 0,0,PAINT | Give a code snippet in #IS-BASIC
A pentagram is a star polygon, consisting of a central pentagon of which each side forms the base of an isosceles triangle. The vertex of each triangle, a point of the star, is 36 degrees.
Task
Draw (or print) a regular pentagram, in any orientation. Use a different color (or tok... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Respond_to_an_unknown_method_call | Respond to an unknown method call | Task
Demonstrate how to make the object respond (sensibly/usefully) to an invocation of a method on it that it does not support through its class definitions.
Note that this is not the same as just invoking a defined method whose name is given dynamically; the method named at the point of invocation must not be defin... | #JavaScript | JavaScript |
obj = new Proxy({},
{ get : function(target, prop)
{
if(target[prop] === undefined)
return function() {
console.log('an otherwise undefined function!!');
};
else
return target... | Give a code snippet in #JavaScript
Task
Demonstrate how to make the object respond (sensibly/usefully) to an invocation of a method on it that it does not support through its class definitions.
Note that this is not the same as just invoking a defined method whose name is given dynamically; the method named at the p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #Objeck | Objeck |
use Structure;
bundle Default {
class HashOfTwo {
function : Main(args : System.String[]) ~ Nil {
keys := ["1", "2", "3"];
vals := ["a", "b", "c"];
hash := StringHash->New();
each(i : vals) {
hash->Insert(keys[i], vals[i]->As(Base));
};
}
}
}
| Give a code snippet in #Objeck
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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 ... | #MUMPS | MUMPS |
DOWHOLIDAY
;In what years between 2008 and 2121 will December 25 be a Sunday?
;Uses the VA's public domain routine %DTC (Part of the Kernel) named here DIDTC
NEW BDT,EDT,CHECK,CHKFOR,LIST,I,X,Y
;BDT - the beginning year to check
;EDT - the end year to check
;BDT and EDT are year offsets from the epoch date 1/1/... | Give a code snippet in #MUMPS
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 ... | 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... | #Prolog | Prolog | :- dynamic fusc_cache/2.
fusc(0, 0):-!.
fusc(1, 1):-!.
fusc(N, F):-
fusc_cache(N, F),
!.
fusc(N, F):-
0 is N mod 2,
!,
M is N//2,
fusc(M, F),
assertz(fusc_cache(N, F)).
fusc(N, F):-
N1 is (N - 1)//2,
N2 is (N + 1)//2,
fusc(N1, F1),
fusc(N2, F2),
F is F1 + F2,
assert... | Give a code snippet in #Prolog
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 s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bin_given_limits | Bin given limits | You are given a list of n ascending, unique numbers which are to form limits
for n+1 bins which count how many of a large set of input numbers fall in the
range of each bin.
(Assuming zero-based indexing)
bin[0] counts how many inputs are < limit[0]
bin[1] counts how many inputs are >= limit[0] and < limit[1]
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | limits = {23, 37, 43, 53, 67, 83};
data = {95, 21, 94, 12, 99, 4, 70, 75, 83, 93, 52, 80, 57, 5, 53, 86,
65, 17, 92, 83, 71, 61, 54, 58, 47, 16, 8, 9, 32, 84, 7, 87, 46,
19, 30, 37, 96, 6, 98, 40, 79, 97, 45, 64, 60, 29, 49, 36, 43,
55};
limits = {{-\[Infinity]}~Join~limits~Join~{\[Infinity]}};
BinCounts[da... | Give a code snippet in #Mathematica.2FWolfram_Language
You are given a list of n ascending, unique numbers which are to form limits
for n+1 bins which count how many of a large set of input numbers fall in the
range of each bin.
(Assuming zero-based indexing)
bin[0] counts how many inputs are < limit[0]
bin[1]... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Penney%27s_game | Penney's game | Penney's game is a game where two players bet on being the first to see a particular sequence of heads or tails in consecutive tosses of a fair coin.
It is common to agree on a sequence length of three then one player will openly choose a sequence, for example:
Heads, Tails, Heads, or HTH for short.
The other pla... | #Elixir | Elixir | defmodule Penney do
@toss [:Heads, :Tails]
def game(score \\ {0,0})
def game({iwin, ywin}=score) do
IO.puts "Penney game score I : #{iwin}, You : #{ywin}"
[i, you] = @toss
coin = Enum.random(@toss)
IO.puts "#{i} I start, #{you} you start ..... #{coin}"
{myC, yC} = setup(coin)
seq = for ... | Give a code snippet in #Elixir
Penney's game is a game where two players bet on being the first to see a particular sequence of heads or tails in consecutive tosses of a fair coin.
It is common to agree on a sequence length of three then one player will openly choose a sequence, for example:
Heads, Tails, Heads, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Visual_Basic | Visual Basic | Option Explicit
Private Declare Function AllocConsole Lib "kernel32.dll" () As Long
Private Declare Function FreeConsole Lib "kernel32.dll" () As Long
'needs a reference set to "Microsoft Scripting Runtime" (scrrun.dll)
Sub Main()
Call AllocConsole
Dim mFSO As Scripting.FileSystemObject
Dim mStdIn As Scripting... | Give a code snippet in #Visual_Basic
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Infinity | Infinity | Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, return the largest possible po... | #TorqueScript | TorqueScript | function infinity()
{
return 1/0;
} | Give a code snippet in #TorqueScript
Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Oth... | christopher/rosetta-code |
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