task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort | Sorting algorithms/Gnome sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #XPL0 | XPL0 | code ChOut=8, IntOut=11;
proc GnomeSort(A(0..Size-1)); \Sort array A
int A, Size;
int I, J, T;
[I:= 1;
J:= 2;
while I < Size do
if A(I-1) <= A(I) then
[\ for descending sort, use >= for comparison
I:= J;
J:= J+1;
]
else
[T:= A(I-1); A(I-1):= A(I); A(I):= T; \swap... | Give a code snippet in #XPL0
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/Execute_Brain**** | Execute Brain**** | Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly implement the following instructions:... | #PL.2FM | PL/M | 100H:
/* CP/M BDOS CALLS */
BDOS: PROCEDURE (FN, ARG) BYTE;
DECLARE FN BYTE, ARG ADDRESS;
GO TO 5;
END BDOS;
READ$CHAR: PROCEDURE BYTE; RETURN BDOS(1, 0); END READ$CHAR;
WRITE$CHAR: PROCEDURE (CHAR); DECLARE CHAR BYTE;
CHAR = BDOS(2, CHAR); END WRITE$CHAR;
PRINT: PROCEDURE (STRING); DECLARE STRING ADDRE... | Give a code snippet in #PL.2FM
Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly imple... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #SmileBASIC | SmileBASIC | PRINT CHR$(97) 'a
PRINT ASC("a") '97 | Give a code snippet in #SmileBASIC
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Apply_a_callback_to_an_array | Apply a callback to an array | Task
Take a combined set of elements and apply a function to each element.
| #C.23 | C# | int[] intArray = { 1, 2, 3, 4, 5 };
// Simplest method: LINQ, functional
int[] squares1 = intArray.Select(x => x * x).ToArray();
// Slightly fancier: LINQ, query expression
int[] squares2 = (from x in intArray
select x * x).ToArray();
// Or, if you only want to call a function on each element, ju... | Give a code snippet in #C.23
Task
Take a combined set of elements and apply a function to each element.
| 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
| #Futhark | Futhark | Public Sub Main()
Dim bX As Boolean
Print bX
bX = True
Print bX
End | Give a code snippet in #Futhark
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/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Visual_Basic | Visual Basic |
Option Explicit
Dim calls As Long
Sub main()
Const maxi = 4
Const maxj = 9
Dim i As Long, j As Long
For i = 0 To maxi
For j = 0 To maxj
Call print_acker(i, j)
Next j
Next i
End Sub 'main
Sub print_acker(m As Long, n As Long)
calls = 0
Debug.Print "ackermann("; m... | Give a code snippet in #Visual_Basic
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Iterated_digits_squaring | Iterated digits squaring | If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89:
15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89
7 -> 49 -> 97 -> 130 -> 10 -> 1
An example in Python:
>>> step = lambda x: sum(int(d) ** 2 for d in str(x))
>>> iterate = lambda x: x if x in [1, 89] else i... | #AWK | AWK | # Usage: GAWK -f ITERATED_DIGITS_SQUARING.AWK
BEGIN {
# Setup buffer for results up to 9*9*8
for (i = 1; i <= 648; i++) {
k = i
do {
k = squaredigitsum(k)
} while ((k != 1) && (k != 89))
if (k == 1) # This will give us 90 entries
buffer[i] = ""
}
#... | Give a code snippet in #AWK
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89:
15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89
7 -> 49 -> 97 -> 130 -> 10 -> 1
An example in Python:
>>> step = lambda x: sum(int(d) ** 2 for d in str(x))
>>> iterate = lambd... | 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... | #Erlang | Erlang |
-module( read_a_specific_line ).
-export( [from_file/2, task/0] ).
from_file( File, N ) -> line_nr( N, read_a_file_line_by_line:into_list(File) ).
task() ->
Lines = read_a_file_line_by_line:into_list( "read_a_specific_line.erl" ),
Line_7 = line_nr( 7, Lines ),
Line_7.
line_nr( N, Line... | Give a code snippet in #Erlang
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/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, t... | #Python | Python | import urllib.parse as up # urlparse for Python v2
url = up.urlparse('http://user:pass@example.com:8081/path/file.html;params?query1=1#fragment')
print('url.scheme = ', url.scheme)
print('url.netloc = ', url.netloc)
print('url.hostname = ', url.hostname)
print('url.port = ', url.port)
print('url.path = ', url.path)... | Give a code snippet in #Python
URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Naming_conventions | Naming conventions | Many languages have naming conventions regarding the identifiers used in the language, its libraries, and programs written in the language. Such conventions, which may be classified as de facto or de jure depending on how they are enforced,
often take the form of rules regarding prefixes, suffixes, and the use of upper... | #6502_Assembly | 6502 Assembly | MODE ℵ SIMPLEOUT = UNION (≮ℒ INT≯, ≮ℒ REAL≯, ≮ℒ COMPL≯, BOOL, ≮ℒ BITS≯, CHAR, [ ] CHAR);
PROC ℓ cos = (ℒ REAL x) ℒ REAL: ¢ a ℒ real value close to the cosine of 'x' ¢;
PROC ℓ complex cos = (ℒ COMPL z) ℒ COMPL: ¢ a ℒ complex value close to the cosine of 'z' ¢;
PROC ℓ arccos = (ℒ REAL x) ℒ REAL: ¢ if ABS x ≤ ℒ 1... | Give a code snippet in #6502_Assembly
Many languages have naming conventions regarding the identifiers used in the language, its libraries, and programs written in the language. Such conventions, which may be classified as de facto or de jure depending on how they are enforced,
often take the form of rules regarding p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_matching | String matching |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Lingo | Lingo | a = "Hello world!"
b = "Hello"
-- Determining if the first string starts with second string
put a starts b
-- 1
-- Determining if the first string contains the second string at any location
put a contains b
-- 1
-- Determining if the first string ends with the second string
put a.char[a.length-b.length+1..a.lengt... | Give a code snippet in #Lingo
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_intersection_of_two_lines | Find the intersection of two lines | [1]
Task
Find the point of intersection of two lines in 2D.
The 1st line passes though (4,0) and (6,10) .
The 2nd line passes though (0,3) and (10,7) .
| #Phix | Phix | with javascript_semantics
enum X, Y
function abc(sequence s,e)
-- yeilds {a,b,c}, corresponding to ax+by=c
atom a = e[Y]-s[Y], b = s[X]-e[X], c = a*s[X]+b*s[Y]
return {a,b,c}
end function
procedure intersect(sequence s1, e1, s2, e2)
atom {a1,b1,c1} = abc(s1,e1),
{a2,b2,c2} = abc(s2,e2),
... | Give a code snippet in #Phix
[1]
Task
Find the point of intersection of two lines in 2D.
The 1st line passes though (4,0) and (6,10) .
The 2nd line passes though (0,3) and (10,7) .
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Jaro_similarity | Jaro similarity | The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that 0 equates to no similarities and 1 is an exact match.
Definition
The... | #Factor | Factor | USING: formatting fry generalizations kernel locals make math
math.order sequences sequences.extras ;
IN: rosetta-code.jaro-distance
: match? ( s1 s2 n -- ? )
[ pick nth swap indices nip ] [ 2nip ]
[ drop [ length ] bi@ max 2/ 1 - ] 3tri
'[ _ - abs _ <= ] any? ;
: matches ( s1 s2 -- seq )
over lengt... | Give a code snippet in #Factor
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that 0 equates to no similarities and 1 is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers/Pascal%27s_triangle | Catalan numbers/Pascal's triangle | Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that generates Catalan Numbers using onl... | #Rust | Rust |
fn main()
{let n=15usize;
let mut t= [0; 17];
t[1]=1;
let mut j:usize;
for i in 1..n+1
{
j=i;
loop{
if j==1{
break;
}
t[j]=t[j] + t[j-1];
j=j-1;
}
t[i+1]= t[i];
j=i+1;
loop{
if j==1{
break;
}
t[j]=t[j] + t[j-1];
j=j-1;
}
print!("{} ", t[i+1]-t[i]);
}
}
| Give a code snippet in #Rust
Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that gener... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap | Bitmap | Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB color,
one to set a given pixe... | #Scheme | Scheme | (define (make-list length object)
(if (= length 0)
(list)
(cons object (make-list (- length 1) object))))
(define (list-fill! list object)
(if (not (null? list))
(begin (set-car! list object) (list-fill! (cdr list) object))))
(define (list-set! list element object)
(if (= element 1)
(s... | Give a code snippet in #Scheme
Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gaussian_elimination | Gaussian elimination | Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| #Wren | Wren | import "/trait" for Stepped
var ta = [
[1.00, 0.00, 0.00, 0.00, 0.00, 0.00],
[1.00, 0.63, 0.39, 0.25, 0.16, 0.10],
[1.00, 1.26, 1.58, 1.98, 2.49, 3.13],
[1.00, 1.88, 3.55, 6.70, 12.62, 23.80],
[1.00, 2.51, 6.32, 15.88, 39.90, 100.28],
[1.00, 3.14, 9.87, 31.01, 97.41, 306.02]
]
... | Give a code snippet in #Wren
Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Ursala | Ursala | #import nat
#import flo
mean = ~&?\0.! div^/plus:-0. float+ length
#cast %e
example = mean <5.,3.,-2.,6.,-4.> | Give a code snippet in #Ursala
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 est... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RIPEMD-160 | RIPEMD-160 | RIPEMD-160 is another hash function; it computes a 160-bit message digest.
There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160.
For padding the message, RIPEMD-160 acts like MD4 (RFC 1320).
Find the RIPEMD-160 message digest of a string of octets.
Use the ASCII encoded string “Rosetta Cod... | #Swift | Swift | // Circular left shift: http://en.wikipedia.org/wiki/Circular_shift
// Precendence should be the same as <<
infix operator ~<< { precedence 160 associativity none }
public func ~<< (lhs: UInt32, rhs: Int) -> UInt32 {
return (lhs << UInt32(rhs)) | (lhs >> UInt32(32 - rhs));
}
public struct Block {
p... | Give a code snippet in #Swift
RIPEMD-160 is another hash function; it computes a 160-bit message digest.
There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160.
For padding the message, RIPEMD-160 acts like MD4 (RFC 1320).
Find the RIPEMD-160 message digest of a string of octets.
Use the AS... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #jq | jq | def s: "一二三四五六七八九十"; | Give a code snippet in #jq
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generic_swap | Generic swap | Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides genericity.
If variables are typed in t... | #Gambas | Gambas | Public Sub Main()
Dim vA As Variant = " World"
Dim vB As Variant = 1
Swap vA, vB
Print vA; vB
End | Give a code snippet in #Gambas
Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides generici... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #Julia | Julia | using Statistics | Give a code snippet in #Julia
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_reversal_game | Number reversal game | Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score is the count of the reversa... | #SenseTalk | SenseTalk |
// set the initial list of digits
set currentList to 1..9 sorted by random of a million
// make sure we don't start off already sorted
repeat while currentList equals 1..9
sort currentList by random of a million
end repeat
// ask until it is solved
repeat while currentList isn't equal to 1..9
add 1 to numberOfT... | Give a code snippet in #SenseTalk
Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
Th... | 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
| #PureBasic | PureBasic | Dim keys.s(3)
Dim vals.s(3)
NewMap Hash.s()
keys(0)="a" : keys(1)="b" : keys(2)="c" : keys(3)="d"
vals(0)="1" : vals(1)="2" : vals(2)="3" : vals(3)="4"
For n = 0 To 3
Hash(keys(n))= vals(n)
Next
ForEach Hash()
Debug Hash()
Next | Give a code snippet in #PureBasic
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/Morse_code | Morse code | Morse code
It has been in use for more than 175 years — longer than any other electronic encoding system.
Task
Send a string as audible Morse code to an audio device (e.g., the PC speaker).
As the standard Morse code does not contain all possible characters,
you may either ignore unknown characters in the file... | #OCaml | OCaml | let codes = [
'a', ".-"; 'b', "-..."; 'c', "-.-.";
'd', "-.."; 'e', "."; 'f', "..-.";
'g', "--."; 'h', "...."; 'i', "..";
'j', ".---"; 'k', "-.-"; 'l', ".-..";
'm', "--"; 'n', "-."; 'o', "---";
'p', ".--."; 'q', "--.-"; 'r', ".-.";
's', "..."; 't', "-"; 'u', "..... | Give a code snippet in #OCaml
Morse code
It has been in use for more than 175 years — longer than any other electronic encoding system.
Task
Send a string as audible Morse code to an audio device (e.g., the PC speaker).
As the standard Morse code does not contain all possible characters,
you may either ignore... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #FBSL | FBSL |
Func Identity(n)=Array id[n,n];[id]:=[1].
Identity(7)
[id]
| Give a code snippet in #FBSL
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ... | #VBA | VBA | Const Order = 4
Function InCarpet(ByVal x As Integer, ByVal y As Integer)
Do While x <> 0 And y <> 0
If x Mod 3 = 1 And y Mod 3 = 1 Then
InCarpet = " "
Exit Function
End If
x = x \ 3
y = y \ 3
Loop
InCarpet = "#"
End Function
Public Sub sierpinski_... | Give a code snippet in #VBA
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## #... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Efene | Efene | compare = fn (A, B) {
if A == B {
io.format("~p equals ~p~n", [A, B])
}
else {
ok
}
if A < B {
io.format("~p is less than ~p~n", [A, B])
}
else {
ok
}
if A > B {
io.format("~p is greater than ~p~n", [A, B])
}
else {
ok... | Give a code snippet in #Efene
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Single | Inheritance/Single | This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.
Usually inherited properties... | #Perl | Perl | package Animal;
#functions go here...
1; | Give a code snippet in #Perl
This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/First_class_environments | First class environments | According to Wikipedia, "In computing, a first-class object ... is an entity that can be constructed at run-time, passed as a parameter, returned from a subroutine, or assigned into a variable".
Often this term is used in the context of "first class functions". In an analogous way, a programming language may support "... | #Haskell | Haskell | hailstone n
| n == 1 = 1
| even n = n `div` 2
| odd n = 3*n + 1 | Give a code snippet in #Haskell
According to Wikipedia, "In computing, a first-class object ... is an entity that can be constructed at run-time, passed as a parameter, returned from a subroutine, or assigned into a variable".
Often this term is used in the context of "first class functions". In an analogous way, a p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #BBC_BASIC | BBC BASIC | MAXPERIOD = 10
FOR n = 1 TO 5
PRINT "Number = ";n TAB(12) " SMA3 = ";FNsma(n,3) TAB(30) " SMA5 = ";FNsma(n,5)
NEXT
FOR n = 5 TO 1 STEP -1
PRINT "Number = ";n TAB(12) " SMA3 = ";FNsma(n,3) TAB(30) " SMA5 = ";FNsma(n,5)
NEXT
END
DEF FNsma(number, period%)
... | Give a code snippet in #BBC_BASIC
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_manipulation | Date manipulation | Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| #Icon_and_Unicon | Icon and Unicon | link datetime
procedure main()
write("input = ",s := "March 7 2009 7:30pm EST" )
write("+12 hours = ",SecToTZDateLine(s := TZDateLineToSec(s) + 12*3600,"EST"))
write(" = ",SecToTZDateLine(s,"UTC"))
write(" = ",SecToTZDateLine(s,"NST"))
end
procedure SecToTZDateLine(s,tz) #: returns ... | Give a code snippet in #Icon_and_Unicon
Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/First_class_environments | First class environments | According to Wikipedia, "In computing, a first-class object ... is an entity that can be constructed at run-time, passed as a parameter, returned from a subroutine, or assigned into a variable".
Often this term is used in the context of "first class functions". In an analogous way, a programming language may support "... | #BBC_BASIC | BBC BASIC | DIM @environ$(12)
@% = 4 : REM Column width
REM Initialise:
FOR E% = 1 TO 12
PROCsetenvironment(@environ$(E%))
seq% = E%
cnt% = 0
@environ$(E%) = FNgetenvironment
NEXT
REM Run hailstone sequences:
REPEAT
T% = 0
FOR E% = 1 TO 1... | Give a code snippet in #BBC_BASIC
According to Wikipedia, "In computing, a first-class object ... is an entity that can be constructed at run-time, passed as a parameter, returned from a subroutine, or assigned into a variable".
Often this term is used in the context of "first class functions". In an analogous way, a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available,... | #Dao | Dao | # use [] to create numeric arrays of int, float, double or complex types:
a = [ 1, 2, 3 ] # a vector
b = [ 1, 2; 3, 4 ] # a 2X2 matrix
# use {} to create normal arrays of any types:
c = { 1, 2, 'abc' }
d = a[1]
e = b[0,1] # first row, second column
f = c[1] | Give a code snippet in #Dao
This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retriev... | 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 ... | #ABAP | ABAP | report zday_of_week
data: lv_start type i value 2007,
lv_n type i value 114,
lv_date type sy-datum,
lv_weekday type string,
lv_day type c,
lv_year type n length 4.
write 'December 25 is a Sunday in: '.
do lv_n times.
lv_year = lv_start + sy-index.
concatenate lv_year '12' '25' into... | Give a code snippet in #ABAP
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years between 2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_three_variables | Sort three variables |
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
... | #Fortran | Fortran | TYPE(MONGREL)
INTEGER TYPEIS
INTEGER VI
REAL VF
CHARACTER*(enuff) VC
...etc...
END TYPE MONGREL
TYPE (MONGREL) DOG | Give a code snippet in #Fortran
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #REALbasic | REALbasic |
Declare Function CreateFileW Lib "Kernel32" (FileName As WString, DesiredAccess As Integer, ShareMode As Integer, SecurityAttributes As Integer, _
CreateDisposition As Integer, Flags As Integer, Template As Integer) As Integer
Declare Function WriteFile Lib "Kernel32" (fHandle As Integer, writeData As Ptr... | Give a code snippet in #REALbasic
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Flush_the_keyboard_buffer | Keyboard input/Flush the keyboard buffer | Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| #ARM_Assembly | ARM Assembly |
/* Programme assembleur ARM Raspberry */
/* modèle B 512MO */
/* REMARK 1 : this program use routines in a include file
see task Include a file language arm assembly
for the routine affichageMess conversion10
see at end of this program the instruction include */
/************************************... | Give a code snippet in #ARM_Assembly
Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_management | Window management | Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of interest may or may not have b... | #Julia | Julia | using Gtk
function controlwindow(win, lab)
sleep(4)
set_gtk_property!(lab, :label, "Hiding...")
sleep(1)
println("Hiding widow")
set_gtk_property!(win, :visible, false)
sleep(5)
set_gtk_property!(lab, :label, "Showing...")
println("Showing window")
set_gtk_property!(win, :visible, ... | Give a code snippet in #Julia
Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #JavaScript | JavaScript | var fso = new ActiveXObject("Scripting.FileSystemObject");
fso.FileExists('input.txt');
fso.FileExists('c:/input.txt');
fso.FolderExists('docs');
fso.FolderExists('c:/docs'); | Give a code snippet in #JavaScript
Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it work... | 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... | #bootBASIC | bootBASIC | 10 print 1/0 | Give a code snippet in #bootBASIC
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. Otherw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hostname | Hostname | Task
Find the name of the host on which the routine is running.
| #Toka | Toka | 2 import gethostname
1024 chars is-array foo
foo 1024 gethostname
foo type | Give a code snippet in #Toka
Task
Find the name of the host on which the routine is running.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/4-rings_or_4-squares_puzzle | 4-rings or 4-squares puzzle | 4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of the four large squares add up to
t... | #JavaScript | JavaScript | (() => {
// 4-rings or 4-squares puzzle ------------------------
// rings :: noRepeatedDigits -> DigitList -> solutions
// rings :: Bool -> [Int] -> [[Int]]
const rings = (uniq, digits) => {
return 0 < digits.length ? (() => {
const
ns = sortBy(flip(compare), digi... | Give a code snippet in #JavaScript
4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Introspection | Introspection | Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop).
Extra credit
Repor... | #REXX | REXX | /*output from parse version (almost all REXX versions) */
/* theREXXinterpreterName level mm Mon yyyy */
parse version . level .
if level<4 then exit | Give a code snippet in #REXX
Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Display_an_outline_as_a_nested_table | Display an outline as a nested table |
Display an outline as a nested table.
Parse the outline to a tree,
count the leaves descending from each node,
and write out a table with 'colspan' values
measuring the indent of each line,
translating the indentation to a nested structure,
and padding the tree to even depth.
defining the width of a ... | #Wren | Wren | import "/dynamic" for Struct
import "/fmt" for Fmt
var NNode = Struct.create("NNode", ["name", "children"])
var INode = Struct.create("INode", ["level", "name"])
var toNest // recursive function
toNest = Fn.new { |iNodes, start, level, n|
if (level == 0) n.name = iNodes[0].name
var i = start + 1
while (... | Give a code snippet in #Wren
Display an outline as a nested table.
Parse the outline to a tree,
count the leaves descending from each node,
and write out a table with 'colspan' values
measuring the indent of each line,
translating the indentation to a nested structure,
and padding the tree to even dep... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/DOM_serialization | XML/DOM serialization | Create a simple DOM and having it serialize to:
<?xml version="1.0" ?>
<root>
<element>
Some text here
</element>
</root>
| #Ada | Ada | with Ada.Text_IO.Text_Streams;
with DOM.Core.Documents;
with DOM.Core.Nodes;
procedure Serialization is
My_Implementation : DOM.Core.DOM_Implementation;
My_Document : DOM.Core.Document;
My_Root_Node : DOM.Core.Element;
My_Element_Node : DOM.Core.Element;
My_Text_Node : DOM.Core.Text;
... | Give a code snippet in #Ada
Create a simple DOM and having it serialize to:
<?xml version="1.0" ?>
<root>
<element>
Some text here
</element>
</root>
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #C.2B.2B | C++ | #include <iomanip>
#include <iostream>
#include <sstream>
#include <vector>
template<typename T>
std::ostream& operator<<(std::ostream& os, const std::vector<T>& v) {
auto it = v.cbegin();
auto end = v.cend();
os << '[';
if (it != end) {
os << *it;
it = std::next(it);
}
while... | Give a code snippet in #C.2B.2B
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/String_case | String case | Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not reversable.
Show any additional... | #Kotlin | Kotlin | // version 1.0.6
fun main(args: Array<String>) {
val s = "alphaBETA"
println(s.toUpperCase())
println(s.toLowerCase())
println(s.capitalize())
println(s.decapitalize())
} | Give a code snippet in #Kotlin
Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #R | R | statmode <- function(v) {
a <- sort(table(v), decreasing=TRUE)
r <- c()
for(i in 1:length(a)) {
if ( a[[1]] == a[[i]] ) {
r <- c(r, as.integer(names(a)[i]))
} else break; # since it's sorted, once we find
# a different value, we can stop
}
r
}
print(statmode(c(1, 3, 6, 6, 6, ... | Give a code snippet in #R
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/Hostname | Hostname | Task
Find the name of the host on which the routine is running.
| #BaCon | BaCon | PRINT "Hostname: ", HOSTNAME$ | Give a code snippet in #BaCon
Task
Find the name of the host on which the routine is running.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Colour_bars/Display | Colour bars/Display | Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| #Wren | Wren | import "graphics" for Canvas, Color
import "dome" for Window
class Game {
static init() {
Window.title = "Color bars"
__width = 400
__height = 400
Canvas.resize(__width, __height)
Window.resize(__width, __height)
var colors = [
Color.hex("000000"), // bl... | Give a code snippet in #Wren
Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Sub Encrypt(s As String, key As Integer)
Dim c As Integer
For i As Integer = 0 To Len(s)
Select Case As Const s[i]
Case 65 To 90
c = s[i] + key
If c > 90 Then c -= 26
s[i] = c
Case 97 To 122
c = s[i] + key
If c > 122 Then c -= 26
... | Give a code snippet in #FreeBASIC
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CSV_data_manipulation | CSV data manipulation | CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, change some values and save the cha... | #Wren | Wren | import "io" for File
var lines = File.read("rc.csv").split("\n").map { |w| w.trim() }.toList
var file = File.create("rc.csv") // overwrite existing file
file.writeBytes(lines[0] + ",SUM\n")
for (line in lines.skip(1)) {
if (line != "") {
var nums = line.split(",").map { |s| Num.fromString(s) }
... | Give a code snippet in #Wren
CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, chang... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Temperature_conversion | Temperature conversion | There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 kelvin.
0 kelvin is absolute z... | #Scala | Scala | object TemperatureConversion extends App {
def kelvinToCelsius(k: Double) = k + 273.15
def kelvinToFahrenheit(k: Double) = k * 1.8 - 459.67
def kelvinToRankine(k: Double) = k * 1.8
if (args.length == 1) {
try {
val kelvin = args(0).toDouble
if (kelvin >= 0) {
println(f"K $kelvin... | Give a code snippet in #Scala
There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generator/Exponential | Generator/Exponential | A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that the internal state of the objec... | #VBA | VBA | Public lastsquare As Long
Public nextsquare As Long
Public lastcube As Long
Public midcube As Long
Public nextcube As Long
Private Sub init()
lastsquare = 1
nextsquare = -1
lastcube = -1
midcube = 0
nextcube = 1
End Sub
Private Function squares() As Long
lastsquare = lastsquare + nextsquare
... | Give a code snippet in #VBA
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #VBA | VBA | Public queue As New Collection
Private Sub push(what As Variant)
queue.Add what
End Sub
Private Function pop() As Variant
If queue.Count > 0 Then
what = queue(1)
queue.Remove 1
Else
what = CVErr(461)
End If
pop = what
End Function
Private Function empty_()
empty_ = ... | Give a code snippet in #VBA
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the ord... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #MiniScript | MiniScript | d = {}
for p in range(1, 100)
for t in range(p, 100, p)
if d.hasIndex(t) then d.remove t else d.push t
end for
end for
print d.indexes.sort | Give a code snippet in #MiniScript
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #XPL0 | XPL0 | include c:\cxpl\codes;
int I;
[for I:= 2 to 8 do
[IntOut(0, I); Text(0, ", ");
I:= I+1;
];
Text(0, "who do we appreciate?");
] | Give a code snippet in #XPL0
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Incr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractran | Fractran | FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway.
A FRACTRAN program is an ordered list of positive fractions
P
=
(
f
1
,
f
2
,
…
,
f
m
)
{\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})}
, together with an initial positive integer input
n
... | #Wren | Wren | import "/big" for BigInt, BigRat
var isPowerOfTwo = Fn.new { |bi| bi & (bi - BigInt.one) == BigInt.zero }
var fractran = Fn.new { |program, n, limit, primesOnly|
var fractions = program.split(" ").where { |s| s != "" }
.map { |s| BigRat.fromRationalString(s) }
... | Give a code snippet in #Wren
FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway.
A FRACTRAN program is an ordered list of positive fractions
P
=
(
f
1
,
f
2
,
…
,
f
m
)
{\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})}
, together with an initial... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parameterized_SQL_statement | Parameterized SQL statement | SQL injection
Using a SQL update statement like this one (spacing is optional):
UPDATE players
SET name = 'Smith, Steve', score = 42, active = TRUE
WHERE jerseyNum = 99
Non-parameterized SQL is the GoTo statement of database programming. Don't do it, and make sure your coworkers don't either. | #Huginn | Huginn | import Database as db;
import Algorithms as algo;
import FileSystem as fs;
main() {
dbPath = "/tmp/parametrized-sql.sqlite";
fs.remove( dbPath );
fs.open( dbPath, fs.OPEN_MODE.WRITE );
conn = db.connect( "sqlite3:///" + dbPath );
// Setup...
conn.query(
"CREATE TABLE Players (\n"
"\tname VARCHAR... | Give a code snippet in #Huginn
SQL injection
Using a SQL update statement like this one (spacing is optional):
UPDATE players
SET name = 'Smith, Steve', score = 42, active = TRUE
WHERE jerseyNum = 99
Non-parameterized SQL is the GoTo statement of database programming. Don't do it, and make sure your coworkers d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #PL.2FI | PL/I |
is_numeric: procedure (text) returns (bit (1));
declare text character (*);
declare x float;
on conversion go to done;
get string(text) edit (x) (E(length(text),0));
return ('1'b);
done:
return ('0'b);
end is_numeric; | Give a code snippet in #PL.2FI
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
... | 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 ... | #Scheme | Scheme | (error "Goodbye, World!") | Give a code snippet in #Scheme
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/Jump_anywhere | Jump anywhere | Imperative programs
conditional structures
loops
local jumps
This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports.
For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to use these jumps for different... | #Wren | Wren | var func = Fn.new {
for (i in 1..10) {
if (i == 1) continue // jumps to next iteration when 'i' equals 1
System.print("i = %(i)")
if (i > 4) break // exits the loop when 'i' exceeds 4
}
for (j in 1..10) {
System.print("j = %(j)")
if (j == 3) return // returns fr... | Give a code snippet in #Wren
Imperative programs
conditional structures
loops
local jumps
This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports.
For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #UNIX_Shell | UNIX Shell | #!/bin/sh
# Guess the number
# This simplified program does not check the input is valid
# Use awk(1) to get a random number. If awk(1) not found, exit now.
number=`awk 'BEGIN{print int(rand()*10+1)}'` || exit
echo 'I have thought of a number. Try to guess it!'
echo 'Enter an integer from 1 to 10.'
until read guess... | Give a code snippet in #UNIX_Shell
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams | Anagrams | When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words in them.
Related tasks
Word plays
... | #MUMPS | MUMPS | Anagrams New ii,file,longest,most,sorted,word
Set file="unixdict.txt"
Open file:"r" Use file
For Quit:$ZEOF DO
. New char,sort
. Read word Quit:word=""
. For ii=1:1:$Length(word) Do
. . Set char=$ASCII(word,ii)
. . If char>64,char<91 Set char=char+32
. . Set sort(char)=$Get(sort(char))+1
. . Quit
. Set (so... | Give a code snippet in #MUMPS
When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words in t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Apply_a_callback_to_an_array | Apply a callback to an array | Task
Take a combined set of elements and apply a function to each element.
| #VBA | VBA |
Option Explicit
Sub Main()
Dim arr, i
'init
arr = Array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
'Loop and apply a function (Fibonacci) to each element
For i = LBound(arr) To UBound(arr): arr(i) = Fibonacci(arr(i)): Next
'return
Debug.Print Join(arr, ", ")
End Sub
Private Function Fibonacci(N... | Give a code snippet in #VBA
Task
Take a combined set of elements and apply a function to each element.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For | Loops/For | “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers.
... | #Modula-2 | Modula-2 | MODULE For;
IMPORT InOut;
VAR
i, j: INTEGER;
BEGIN
FOR i := 1 TO 5 DO
FOR j := 1 TO i DO
InOut.Write('*');
END;
InOut.WriteLn
END
END For. | Give a code snippet in #Modula-2
“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract stru... | christopher/rosetta-code | |
http://rosettacode.org/wiki/History_variables | History variables | Storing the history of objects in a program is a common task.
Maintaining the history of an object in a program has traditionally required programmers either to write specific code for handling the historical data, or to use a library which supports history logging.
History variables are variables in a programming la... | #Peloton | Peloton | Turn history on <@ DEFHST>__on</@>
Notify Protium we are interested in the variable mv
<@ DEFHST>mv</@>
Assign a value: <@ LETVARLIT>mv|first value</@><@ SAYVAR>mv</@>
Reassign the value: <@ LETVARLIT>mv|second value</@><@ SAYVAR>mv</@>
Reassign the value: <@ LETVARLIT>mv|third value</@><@ SAYVAR>mv</@>
Dump hist... | Give a code snippet in #Peloton
Storing the history of objects in a program is a common task.
Maintaining the history of an object in a program has traditionally required programmers either to write specific code for handling the historical data, or to use a library which supports history logging.
History variables ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort | Sorting algorithms/Gnome sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Ruby | Ruby | class Array
def gnomesort!
i, j = 1, 2
while i < length
if self[i-1] <= self[i]
i, j = j, j+1
else
self[i-1], self[i] = self[i], self[i-1]
i -= 1
if i == 0
i, j = j, j+1
end
end
end
self
end
end
ary = [7,6,5,9,8,4,3,1,2,0]
ary.gnome... | Give a code snippet in #Ruby
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/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]
... | #Java | Java | import java.util.Arrays;
import java.util.Collections;
import java.util.List;
public class Bins {
public static <T extends Comparable<? super T>> int[] bins(
List<? extends T> limits, Iterable<? extends T> data) {
int[] result = new int[limits.size() + 1];
for (T n : data) {
... | Give a code snippet in #Java
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 ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ... | #Ring | Ring |
load "guilib.ring"
new qapp
{
win1 = new qwidget() {
etwindowtitle("drawing using qpainter")
setgeometry(100,100,500,500)
label1 = new qlabel(win1) {
setgeometry(10,10,400,400)
settext("")
... | Give a code snippet in #Ring
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #NetRexx | NetRexx | /* NetRexx ************************************************************
* show identity matrix of size n
* I consider m[i,j] to represent the matrix
* 09.07.2013 Walter Pachl (translated from REXX Version 2)
**********************************************************************/
options replace format comments java cro... | Give a code snippet in #NetRexx
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Normal_distribution | Statistics/Normal distribution | The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform random number generator and create a ... | #Haskell | Haskell | import Data.Map (Map, empty, insert, findWithDefault, toList)
import Data.Maybe (fromMaybe)
import Text.Printf (printf)
import Data.Function (on)
import Data.List (sort, maximumBy, minimumBy)
import Control.Monad.Random (RandomGen, Rand, evalRandIO, getRandomR)
import Control.Monad (replicateM)
-- Box-Muller
getNorm ... | Give a code snippet in #Haskell
The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform rand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Interactive_programming_(repl) | Interactive programming (repl) | Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
Task
Show how to start this... | #PicoLisp | PicoLisp | $ pil + | Give a code snippet in #PicoLisp
Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shel... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_name | Program name | The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A... | #Haskell | Haskell | import System (getProgName)
main :: IO ()
main = getProgName >>= putStrLn . ("Program: " ++) | Give a code snippet in #Haskell
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the scrip... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Spinning_rod_animation/Text | Spinning rod animation/Text | Task
An animation with the following frames in the following order (if certain characters aren't available or can't be used correctly in the programming language, alternate characters can replace any of these frames) must animate with a delay of 0.25 seconds between each frame, with the previous frame being cleared be... | #ScratchScript | ScratchScript | print "|"
delay 0.25
clear
print "/"
delay 0.25
clear
print "-"
delay 0.25
clear
print "\"
delay 0.25 | Give a code snippet in #ScratchScript
Task
An animation with the following frames in the following order (if certain characters aren't available or can't be used correctly in the programming language, alternate characters can replace any of these frames) must animate with a delay of 0.25 seconds between each frame, w... | 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... | #Common_Lisp | Common Lisp | (defun convert-to-row-echelon-form (matrix)
(let* ((dimensions (array-dimensions matrix))
(row-count (first dimensions))
(column-count (second dimensions))
(lead 0))
(labels ((find-pivot (start lead)
(let ((i start))
(loop
:while (zerop (aref matrix i lead))
:do (progn
(incf i)... | Give a code snippet in #Common_Lisp
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 con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_HTML_table | Create an HTML table | Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers.
The... | #COBOL | COBOL |
IDENTIFICATION DIVISION.
PROGRAM-ID. Table.
AUTHOR. Bill Gunshannon.
INSTALLATION. Home.
DATE-WRITTEN. 1 January 2022.
************************************************************
** Program Abstract:
** Data values are hardcoded in this example but they
... | Give a code snippet in #COBOL
Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled wit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hunt_the_Wumpus | Hunt the Wumpus | This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game is set in a cave that consists ... | #Swift | Swift |
import Foundation
//All rooms in cave
var cave: [Int:[Int]] = [
1: [2, 3, 4],
2: [1, 5, 6],
3: [1, 7, 8],
4: [1, 9, 10],
5: [2, 9, 11],
6: [2, 7, 12],
7: [3, 6, 13],
8: [3, 10, 14],
9: [4, 5, 15],
10: [4, 8, 16],
11: [5, 12, 17],
12: [6, 11, 18],
13: [7, 14, 18],
... | Give a code snippet in #Swift
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Odd_word_problem | Odd word problem | Task
Write a program that solves the odd word problem with the restrictions given below.
Description
You are promised an input stream consisting of English letters and punctuations.
It is guaranteed that:
the words (sequence of consecutive letters) are delimited by one and only one punctuation,
the stream will... | #Go | Go | package main
import (
"bytes"
"fmt"
"io"
"os"
"unicode"
)
func main() {
owp(os.Stdout, bytes.NewBufferString("what,is,the;meaning,of:life."))
fmt.Println()
owp(os.Stdout, bytes.NewBufferString("we,are;not,in,kansas;any,more."))
fmt.Println()
}
func owp(dst io.Writer, src io.Rea... | Give a code snippet in #Go
Task
Write a program that solves the odd word problem with the restrictions given below.
Description
You are promised an input stream consisting of English letters and punctuations.
It is guaranteed that:
the words (sequence of consecutive letters) are delimited by one and only one p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multi-dimensional_array | Multi-dimensional array | For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value to update the indexed value.
... | #jq | jq | # The input is used to initialize the elements of the
# multi-dimensional array:
def multiarray(d):
. as $in
| if (d|length) == 1 then [range(0;d[0]) | $in]
else multiarray(d[1:]) | multiarray( d[0:1] )
end; | Give a code snippet in #jq
For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Peaceful_chess_queen_armies | Peaceful chess queen armies | In chess, a queen attacks positions from where it is, in straight lines up-down and left-right as well as on both its diagonals. It attacks only pieces not of its own colour.
⇖
⇑
⇗
⇐
⇐
♛
⇒
⇒
⇙
⇓
⇘
⇙
⇓
⇘
⇓
The goal of Peaceful chess queen armies is to arrange m black queens and m white queens ... | #C.2B.2B | C++ | #include <iostream>
#include <vector>
enum class Piece {
empty,
black,
white
};
typedef std::pair<int, int> position;
bool isAttacking(const position &queen, const position &pos) {
return queen.first == pos.first
|| queen.second == pos.second
|| abs(queen.first - pos.first) == abs(... | Give a code snippet in #C.2B.2B
In chess, a queen attacks positions from where it is, in straight lines up-down and left-right as well as on both its diagonals. It attacks only pieces not of its own colour.
⇖
⇑
⇗
⇐
⇐
♛
⇒
⇒
⇙
⇓
⇘
⇙
⇓
⇘
⇓
The goal of Peaceful chess queen armies is to arrange m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Scheme | Scheme | (define (addsub x y)
(values (+ x y) (- x y))) | Give a code snippet in #Scheme
Task
Show how to return more than one value from a function.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Balanced_brackets | Balanced brackets | Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nest.
Examples
(empty) ... | #Clojure | Clojure | (defn gen-brackets [n]
(->> (concat (repeat n \[) (repeat n \]))
shuffle
(apply str ,)))
(defn balanced? [s]
(loop [[first & coll] (seq s)
stack '()]
(if first
(if (= first \[)
(recur coll (conj stack \[))
(when (= (peek stack) \[)
(recur coll (pop stack))))
(zero? (count stac... | Give a code snippet in #Clojure
Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Death_Star | Death Star |
Task
Display a region that consists of a large sphere with part of a smaller sphere removed from it as a result of geometric subtraction.
(This will basically produce a shape like a "death star".)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
| #LSL | LSL | default {
state_entry() {
llSetPrimitiveParams([PRIM_NAME, "RosettaCode DeathStar"]);
llSetPrimitiveParams([PRIM_DESC, llGetObjectName()]);
llSetPrimitiveParams([PRIM_TYPE, PRIM_TYPE_SPHERE, PRIM_HOLE_CIRCLE, <0.0, 1.0, 0.0>, 0.0, <0.0, 0.0, 0.0>, <0.12, 1.0, 0.0>]);
llSetPrimitivePa... | Give a code snippet in #LSL
Task
Display a region that consists of a large sphere with part of a smaller sphere removed from it as a result of geometric subtraction.
(This will basically produce a shape like a "death star".)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
write language name... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Modula-2 | Modula-2 | MODULE Sequence;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,ReadChar;
VAR
buf : ARRAY[0..63] OF CHAR;
i : CARDINAL;
BEGIN
i := 1;
WHILE i>0 DO
FormatString("%c ", buf, i);
WriteString(buf);
INC(i)
END;
ReadChar
END Sequence. | Give a code snippet in #Modula-2
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greyscale_bars/Display | Greyscale bars/Display | The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha... | #Kotlin | Kotlin | // version 1.1
import java.awt.Color
import java.awt.Graphics
import javax.swing.JFrame
class GreyBars : JFrame("grey bars example!") {
private val w: Int
private val h: Int
init {
w = 640
h = 320
setSize(w, h)
defaultCloseOperation = JFrame.EXIT_ON_CLOSE
isVisi... | Give a code snippet in #Kotlin
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we ... | 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 -... | #Lua | Lua | -- Global variables
http = require("socket.http")
keys = {"VOICEMAIL", "abc", "def", "ghi", "jkl", "mno", "pqrs", "tuv", "wxyz"}
dictFile = "http://www.puzzlers.org/pub/wordlists/unixdict.txt"
-- Return the sequence of keys required to type a given word
function keySequence (str)
local sequence, noMatch, letter =... | Give a code snippet in #Lua
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/Bioinformatics/base_count | Bioinformatics/base count | Given this string representing ordered DNA bases:
CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG
CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG
AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGAT
GGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTT
CGATTCTGCTTATAACACTATGTTCTTATGAAATGGATGTTCTGAGTTGG
TCAGTCCCAATGTG... | #C.2B.2B | C++ | #include <map>
#include <string>
#include <iostream>
#include <iomanip>
const std::string DEFAULT_DNA = "CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG"
"CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG"
"AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATC... | Give a code snippet in #C.2B.2B
Given this string representing ordered DNA bases:
CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG
CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG
AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGAT
GGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTT
CGATTCTGCTTATAACACTATGTTCTTATGAA... | 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 ... | #PHP | PHP | fprintf(STDERR, "Goodbye, World!\n"); | Give a code snippet in #PHP
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/Primality_by_trial_division | Primality by trial division | Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
... | #Ol | Ol |
(define (prime? number)
(define max (sqrt number))
(define (loop divisor)
(or (> divisor max)
(and (> (modulo number divisor) 0)
(loop (+ divisor 2)))))
(or (= number 1)
(= number 2)
(and
(> (modulo number 2) 0)
(loop 3))))
| Give a code snippet in #Ol
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CRC-32 | CRC-32 |
Task
Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.
The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.
Algorithms are described on Computation of CRC in Wikipedia.
This variant of CRC-32 uses LSB-first order, sets the initial CRC to FFFFFFFF16, and... | #VAX_Assembly | VAX Assembly | EDB88320 0000 1 poly: .long ^xedb88320 ;crc32
00000044 0004 2 table: .blkl 16
0044 3
4C 58 21 0000004C'010E0000' 0044 4 fmt: .ascid "!XL" ;resu... | Give a code snippet in #VAX_Assembly
Task
Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.
The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.
Algorithms are described on Computation of CRC in Wikipedia.
This variant of CRC-32 uses LSB-first order, s... | 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... | #Erlang | Erlang | repeat(X,N) ->
lists:flatten(lists:duplicate(N,X)). | Give a code snippet in #Erlang
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/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #Inform_7 | Inform 7 | R is a room. To quit: (- quit; -). When play begins: say entry 1 in Q; say Q in brace notation; quit. Q is a list of text variable. Q is {"R is a room. To quit: (- quit; -). When play begins: say entry 1 in Q; say Q in brace notation; quit. Q is a list of text variable. Q is "} | Give a code snippet in #Inform_7
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mouse_position | Mouse position | Task
Get the current location of the mouse cursor relative to the active window.
Please specify if the window may be externally created.
| #Smalltalk | Smalltalk |
World activeHand position. " (394@649.0)"
| Give a code snippet in #Smalltalk
Task
Get the current location of the mouse cursor relative to the active window.
Please specify if the window may be externally created.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Miller%E2%80%93Rabin_primality_test | Miller–Rabin primality test |
This page uses content from Wikipedia. The original article was at Miller–Rabin primality test. 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)
The Miller–Rabin primality test or Rabin–Miller prima... | #Crystal | Crystal | require "big"
module Primes
module MillerRabin
def prime?(k = 15) # increase k for more confidence
neg_one_mod = d = self - 1
s = 0
while d.even?; d >>= 1; s += 1 end # d is odd after s shifts
k.times do
b = 2 + rand(self - 4) # random witness base b
y ... | Give a code snippet in #Crystal
This page uses content from Wikipedia. The original article was at Miller–Rabin primality test. 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)
The Miller–Rabin pri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #Visual_Basic | Visual Basic | Declare Function MultiByteToWideChar Lib "kernel32.dll" ( _
ByVal CodePage As Long, _
ByVal dwFlags As Long, _
ByVal lpMultiByteStr As Long, _
ByVal cchMultiByte As Long, _
ByVal lpWideCharStr As Long, _
ByVal cchWideChar As Long) As Long
Const CP_UTF8 As Long = 65001
Sub Main()
Dim fn A... | Give a code snippet in #Visual_Basic
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplishe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Super-d_numbers | Super-d numbers | A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or super-d.
Task
Write a... | #Kotlin | Kotlin | import java.math.BigInteger
fun superD(d: Int, max: Int) {
val start = System.currentTimeMillis()
var test = ""
for (i in 0 until d) {
test += d
}
var n = 0
var i = 0
println("First $max super-$d numbers:")
while (n < max) {
i++
val value: Any = BigInteger.val... | Give a code snippet in #Kotlin
A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Forward_difference | Forward difference | Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B should have one fewer elem... | #AppleScript | AppleScript | -- forwardDifference :: Num a => [a] -> [a]
on forwardDifference(xs)
zipWith(my subtract, xs, rest of xs)
end forwardDifference
-- nthForwardDifference :: Num a => Int -> [a] -> [a]
on nthForwardDifference(xs, i)
|index|(iterate(forwardDifference, xs), 1 + i)
end nthForwardDifference
-------------------... | Give a code snippet in #AppleScript
Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_names | Number names | Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than positive integers (like zero, negat... | #SQL | SQL |
SELECT val, to_char(to_date(val,'j'),'jsp') name
FROM
(
SELECT
round( dbms_random.VALUE(1, 5373484)) val
FROM dual
CONNECT BY level <= 5
);
SELECT to_char(to_date(5373485,'j'),'jsp') FROM dual;
| Give a code snippet in #SQL
Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than positi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #Scala | Scala |
sealed trait List[+A]
case class Cons[+A](head: A, tail: List[A]) extends List[A]
case object Nil extends List[Nothing]
object List {
def apply[A](as: A*): List[A] =
if (as.isEmpty) Nil else Cons(as.head, apply(as.tail: _*))
}
| Give a code snippet in #Scala
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element def... | christopher/rosetta-code |
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