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/Permutation_test | Permutation test | Permutation test
You are encouraged to solve this task according to the task description, using any language you may know.
A new medical treatment was tested on a population of
n
+
m
{\displaystyle n+m}
volunteers, with each volunteer randomly assigned either to a group of
n
{\displaystyle n}
treatment... | #11l | 11l | V data = [85, 88, 75, 66, 25, 29, 83, 39, 97,
68, 41, 10, 49, 16, 65, 32, 92, 28, 98]
F pick(at, remain, accu, treat)
I remain == 0
R I accu > treat {1} E 0
R pick(at - 1, remain - 1, accu + :data[at - 1], treat) +
(I at > remain {pick(at - 1, remain, accu, treat)} E 0)
V treat = 0
V total =... | Give a code snippet in #11l
Permutation test
You are encouraged to solve this task according to the task description, using any language you may know.
A new medical treatment was tested on a population of
n
+
m
{\displaystyle n+m}
volunteers, with each volunteer randomly assigned either to a group of
n
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Special_characters | Special characters | Special characters are symbols (single characters or sequences of characters) that have a "special" built-in meaning in the language and typically cannot be used in identifiers.
Escape sequences are methods that the language uses to remove the special meaning from the symbol, enabling it to be used as a normal charact... | #ALGOL_68 | ALGOL 68 | printf(($"flip:"g"!"l$,flip));
printf(($"flop:"g"!"l$,flop));
printf(($"blank:"g"!"l$,blank));
printf(($"error char:"g"!"l$,error char));
printf(($"null character:"g"!"l$,null character)) | Give a code snippet in #ALGOL_68
Special characters are symbols (single characters or sequences of characters) that have a "special" built-in meaning in the language and typically cannot be used in identifiers.
Escape sequences are methods that the language uses to remove the special meaning from the symbol, enabling... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_concatenation | String concatenation | String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string literal.
To illustrate the operat... | #SAS | SAS | data _null_;
a="Hello,";
b="World!";
c=a !! " " !! b;
put c;
*Alternative using the catx function;
c=catx (" ", a, b);
put c;
run; | Give a code snippet in #SAS
String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string liter... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arena_storage_pool | Arena storage pool | Dynamically allocated objects take their memory from a heap.
The memory for an object is provided by an allocator which maintains the storage pool used for the heap.
Often a call to allocator is denoted as
P := new T
where T is the type of an allocated object, and P is a reference to the object.
The stora... | #Delphi | Delphi |
program Arena_storage_pool;
{$APPTYPE CONSOLE}
uses
Winapi.Windows,
System.SysUtils,
system.generics.collections;
type
TPool = class
private
FStorage: TList<Pointer>;
public
constructor Create;
destructor Destroy; override;
function Allocate(aSize: Integer): Pointer;
function Rel... | Give a code snippet in #Delphi
Dynamically allocated objects take their memory from a heap.
The memory for an object is provided by an allocator which maintains the storage pool used for the heap.
Often a call to allocator is denoted as
P := new T
where T is the type of an allocated object, and P is a ref... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #HicEst | HicEst | DLG(Edit=A, DNum, MIn=-1000, MAx=1000, E=B, DN, MI=-1000, MA=1000)
WRITE(Messagebox, Name) A, B, "Sum = ", A+B | Give a code snippet in #HicEst
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multifactorial | Multifactorial | The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(... | #F.23 | F# | let rec mfact d = function
| n when n <= d -> n
| n -> n * mfact d (n-d)
[<EntryPoint>]
let main argv =
let (|UInt|_|) = System.UInt32.TryParse >> function | true, v -> Some v | false, _ -> None
let (maxDegree, maxN) =
match argv with
| [| UInt d; UInt n |] -> (int d, int n)
... | Give a code snippet in #F.23
The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\disp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Host_introspection | Host introspection | Print the word size and endianness of the host machine.
See also: Variable size/Get
| #Slate | Slate | inform: 'Endianness: ' ; Platform current endianness.
inform: 'Word Size: ' ; (Platform current bytesPerWord * 8) printString. | Give a code snippet in #Slate
Print the word size and endianness of the host machine.
See also: Variable size/Get
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #ALGOL_W | ALGOL W | begin
% returns a string representing the number in s incremented %
% As strings are fixed length, the significant length of s must %
% be specified in length %
% s must contain an unsigned integer %
% If the string is invalid or ... | Give a code snippet in #ALGOL_W
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Subtractive_generator | Subtractive generator | A subtractive generator calculates a sequence of random numbers, where each number is congruent to the subtraction of two previous numbers from the sequence.
The formula is
r
n
=
r
(
n
−
i
)
−
r
(
n
−
j
)
(
mod
m
)
{\displaystyle r_{n}=r_{(n-i)}-r_{(n-j)}{\pmod {m}}}
for some fixed values of... | #Bracmat | Bracmat | 1000000000:?MOD;
tbl$(state,55);
0:?si:?sj;
(subrand-seed=
i,j,p2
. 1:?p2
& mod$(!arg,!MOD):?(0$?state)
& 1:?i
& 21:?j
& whl
' ( !i:<55
& (!j:~<55&!j+-55:?j|)
& !p2:?(!j$?state)
& ( !arg+-1*!p2:?p2:<0
& !p2+!MOD:?p2
|
)
& !(!j$state):?arg
& !... | Give a code snippet in #Bracmat
A subtractive generator calculates a sequence of random numbers, where each number is congruent to the subtraction of two previous numbers from the sequence.
The formula is
r
n
=
r
(
n
−
i
)
−
r
(
n
−
j
)
(
mod
m
)
{\displaystyle r_{n}=r_{(n-i)}-r_{(n-j)}{\pmod... | 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... | #Vala | Vala |
double arithmetic(double[] list){
double mean;
double sum = 0;
if (list.length == 0)
return 0.0;
foreach(double number in list){
sum += number;
} // foreach
mean = sum / list.length;
return mean;
} // end arithmetic mean
public static void main(){
double[] test = {1.0, 2.0, 5.0, -5.0, 9.5, 3.14159... | Give a code snippet in #Vala
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 estab... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jewels_and_stones | Jewels and stones | Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case letters. However, in the case ... | #VBA | VBA | Function count_jewels(stones As String, jewels As String) As Integer
Dim res As Integer: res = 0
For i = 1 To Len(stones)
res = res - (InStr(1, jewels, Mid(stones, i, 1), vbBinaryCompare) <> 0)
Next i
count_jewels = res
End Function
Public Sub main()
Debug.Print count_jewels("aAAbbbb", "aA")... | Give a code snippet in #VBA
Jewels and stones
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a function which takes two string parameters: 'stones' and 'jewels' and returns an integer.
Both strings can contain any number of upper or lower case l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Plasma_effect | Plasma effect | The plasma effect is a visual effect created by applying various functions, notably sine and cosine, to the color values of screen pixels. When animated (not a task requirement) the effect may give the impression of a colorful flowing liquid.
Task
Create a plasma effect.
See also
Computer Graphics Tutorial (lod... | #Gosu | Gosu |
uses javax.swing.*
uses java.awt.*
uses java.awt.image.*
uses java.awt.event.ActionEvent
uses java.awt.image.BufferedImage#*
uses java.lang.Math#*
var size = 400
EventQueue.invokeLater(\ -> showPlasma())
function showPlasma() {
var frame = new JFrame("Plasma") {:Resizable = false, :DefaultCloseOperation = JFram... | Give a code snippet in #Gosu
The plasma effect is a visual effect created by applying various functions, notably sine and cosine, to the color values of screen pixels. When animated (not a task requirement) the effect may give the impression of a colorful flowing liquid.
Task
Create a plasma effect.
See also
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Eiffel | Eiffel | class
APPLICATION
create
make
feature {NONE} -- Initialization
make
do
move (4, "A", "B", "C")
end
feature -- Towers of Hanoi
move (n: INTEGER; frm, to, via: STRING)
require
n > 0
do
if n = 1 then
print ("Move disk from pole " + frm + " to pole " + to + "%N")
else
m... | Give a code snippet in #Eiffel
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_squares_of_doubly_even_order | Magic squares of doubly even order | A magic square is an N×N square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant).
A magic square of doubly even order has a size that is a multiple of four (e... | #Visual_Basic_.NET | Visual Basic .NET | Module MagicSquares
Function MagicSquareDoublyEven(n As Integer) As Integer(,)
If n < 4 OrElse n Mod 4 <> 0 Then
Throw New ArgumentException("base must be a positive multiple of 4")
End If
'pattern of count-up vs count-down zones
Dim bits = Convert.ToInt32("1001011001... | Give a code snippet in #Visual_Basic_.NET
A magic square is an N×N square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant).
A magic square of doubly even order... | 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... | #FUZE_BASIC | FUZE BASIC | READ x,y,z
PRINT "Open doors: ";x;" ";
CYCLE
z=x+y
PRINT z;" ";
x=z
y=y+2
REPEAT UNTIL z>=100
DATA 1,3,0
END | Give a code snippet in #FUZE_BASIC
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/CSV_to_HTML_translation | CSV to HTML translation | Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task
Create a function that takes a st... | #Wren | Wren | var csv =
"Character,Speech\n" +
"The multitude,The messiah! Show us the messiah!\n" +
"Brians mother,<angry>Now you listen here! He's not the messiah; " +
"he's a very naughty boy! Now go away!</angry>\n" +
"The multitude,Who are you?\n" +
"Brians mother,I'm his mother; that's who!\n" +
"Th... | Give a code snippet in #Wren
Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task
Cre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Largest_proper_divisor_of_n | Largest proper divisor of n | Task
a(1) = 1; for n > 1, a(n) = largest proper divisor of n, where n < 101 .
| #Draco | Draco | proc nonrec lpd(word n) word:
word d;
if n=1 then
1
else
d := n-1;
while n % d /= 0 do d := d-1 od;
d
fi
corp
proc nonrec main() void:
word n;
for n from 1 upto 100 do
write(lpd(n):3);
if n%10 = 0 then writeln() fi
od
corp | Give a code snippet in #Draco
Task
a(1) = 1; for n > 1, a(n) = largest proper divisor of n, where n < 101 .
| christopher/rosetta-code | |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #PicoLisp | PicoLisp | (let File "test.file"
(and
(info File)
(prinl (stamp (cadr @) (cddr @))) ) # Print date and time in UTC
(call 'touch File) ) # Set modification time to "now" | Give a code snippet in #PicoLisp
Task
Get and set the modification time of a file.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Crystal | Crystal | a = gets.not_nil!.to_i64
b = gets.not_nil!.to_i64
puts "Sum: #{a + b}"
puts "Difference: #{a - b}"
puts "Product: #{a * b}"
puts "Quotient (float division): #{a / b}" # / always returns a float.
puts "Quotient (floor division): #{a // b}"
puts "Remainder: #{a % b}" # Sign of remainder matches that of the second oper... | Give a code snippet in #Crystal
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 Operation... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_subsequential_sum | Greatest subsequential sum | Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are negative, the result must be th... | #Bracmat | Bracmat |
( 0:?max
& :?seq
& -1 -2 3 5 6 -2 -1 4 -4 2 -1
: ?
[%( (
= s sum
. ( sum
= A
. !arg:%?A ?arg&!A+sum$!arg
| 0
)
& ( sum$!sjt:>!max:?max
... | Give a code snippet in #Bracmat
Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #PL.2FM | PL/M | 100H:
/* DECLARE OUTPUT IN TERMS OF CP/M -
PL/M DOES NOT COME WITH ANY STANDARD LIBRARY */
BDOS: PROCEDURE(FUNC, ARG);
DECLARE FUNC BYTE, ARG ADDRESS;
GO TO 5;
END BDOS;
PUT$STRING: PROCEDURE(STR);
DECLARE STR ADDRESS;
CALL BDOS(9, STR);
CALL BDOS(9, .(13,10,'$'));
END PUT$STRING;
/* PRINT... | Give a code snippet in #PL.2FM
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/9_billion_names_of_God_the_integer | 9 billion names of God the integer | This task is a variation of the short story by Arthur C. Clarke.
(Solvers should be aware of the consequences of completing this task.)
In detail, to specify what is meant by a “name”:
The integer 1 has 1 name “1”.
The integer 2 has 2 names “1+1”, and “2”.
The integer 3 has 3 names “1+1+1”, “2+1”, ... | #Elixir | Elixir | defmodule God do
def g(n,g) when g == 1 or n < g, do: 1
def g(n,g) do
Enum.reduce(2..g, 1, fn q,res ->
res + (if q > n-g, do: 0, else: g(n-g,q))
end)
end
end
Enum.each(1..25, fn n ->
IO.puts Enum.map(1..n, fn g -> "#{God.g(n,g)} " end)
end) | Give a code snippet in #Elixir
This task is a variation of the short story by Arthur C. Clarke.
(Solvers should be aware of the consequences of completing this task.)
In detail, to specify what is meant by a “name”:
The integer 1 has 1 name “1”.
The integer 2 has 2 names “1+1”, and “2”.
The integer 3 ha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_calculator_algorithm | Parsing/RPN calculator algorithm | Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the RPN expression generated from the... | #PARI.2FGP | PARI/GP | estack = [];
epush(x) = {
estack = vector(#estack + 1, i, if(i <= #estack, estack[i], x));
return(#estack);
};
epop() = {
local(val = estack[#estack]);
estack = vector(#estack - 1, i, estack[i]);
return(val);
};
registerRPNToken(t) = {
local(o1, o2);
if(type(t) == "t_STR",
if... | Give a code snippet in #PARI.2FGP
Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_easy | Abbreviations, easy | This task is an easier (to code) variant of the Rosetta Code task: Abbreviations, simple.
For this task, the following command table will be used:
Add ALTer BAckup Bottom CAppend Change SCHANGE CInsert CLAst COMPress COpy
COUnt COVerlay CURsor DELete CDelete Down DUPlicate Xedit EXPand EXTract Find
... | #REXX | REXX | /*REXX program validates a user "word" against a "command table" with abbreviations.*/
parse arg uw /*obtain optional arguments from the CL*/
if uw='' then uw= 'riG rePEAT copies put mo rest types fup. 6 poweRin'
say 'user words: ' uw
@= 'Add ALTer BAckup... | Give a code snippet in #REXX
This task is an easier (to code) variant of the Rosetta Code task: Abbreviations, simple.
For this task, the following command table will be used:
Add ALTer BAckup Bottom CAppend Change SCHANGE CInsert CLAst COMPress COpy
COUnt COVerlay CURsor DELete CDelete Down DUPlic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Complex | Arithmetic/Complex | A complex number is a number which can be written as:
a
+
b
×
i
{\displaystyle a+b\times i}
(sometimes shown as:
b
+
a
×
i
{\displaystyle b+a\times i}
where
a
{\displaystyle a}
and
b
{\displaystyle b}
are real numbers, and
i
{\displaystyle i}
is √ -1
Typica... | #Fortran | Fortran | program cdemo
complex :: a = (5,3), b = (0.5, 6.0) ! complex initializer
complex :: absum, abprod, aneg, ainv
absum = a + b
abprod = a * b
aneg = -a
ainv = 1.0 / a
end program cdemo | Give a code snippet in #Fortran
A complex number is a number which can be written as:
a
+
b
×
i
{\displaystyle a+b\times i}
(sometimes shown as:
b
+
a
×
i
{\displaystyle b+a\times i}
where
a
{\displaystyle a}
and
b
{\displaystyle b}
are real numbers, and
i
{\display... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Joy | Joy | DEFINE fib == [small] [] [pred dup pred] [+] binrec. | Give a code snippet in #Joy
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are g... | 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
⋮
⋮
⋮
⋱
... | #Burlesque | Burlesque |
blsq ) 6 -.^^0\/r@\/'0\/.*'1+]\/{\/{rt}\/E!XX}x/+]m[sp
1 0 0 0 0 0
0 1 0 0 0 0
0 0 1 0 0 0
0 0 0 1 0 0
0 0 0 0 1 0
0 0 0 0 0 1
| Give a code snippet in #Burlesque
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/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... | #UNIX_Shell | UNIX Shell | echo alphaBETA | tr '[a-z]' '[A-Z]' # => ALPHABETA
echo alphaBETA | tr '[A-Z]' '[a-z]' # => alphabeta | Give a code snippet in #UNIX_Shell
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
... | #J | J | sleep =: 6!:3
sleeping=: monad define
smoutput 'Sleeping...'
sleep y
smoutput 'Awake!'
) | Give a code snippet in #J
Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Monte | Monte | def fizzBuzz(top):
var t := 1
while (t < top):
if ((t % 3 == 0) || (t % 5 == 0)):
if (t % 15 == 0):
traceln(`$t FizzBuzz`)
else if (t % 3 == 0):
traceln(`$t Fizz`)
else:
traceln(`$t Buzz`)
t += 1
fizzBuzz(10... | Give a code snippet in #Monte
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Machine_code | Machine code | The task requires poking machine code directly into memory and executing it. The machine code is the architecture-specific opcodes which have the simple task of adding two unsigned bytes together and making the result available to the high-level language.
For example, the following assembly language program is given f... | #Draco | Draco | /* 8080 machine code in an array */
[6] byte add_mc = (
0xC1, /* POP B - get return address */
0xD1, /* POP D - get second argument */
0xE1, /* POP H - get first argument */
0x19, /* DAD D - add arguments */
0xC5, /* PUSH B - push return address back... | Give a code snippet in #Draco
The task requires poking machine code directly into memory and executing it. The machine code is the architecture-specific opcodes which have the simple task of adding two unsigned bytes together and making the result available to the high-level language.
For example, the following assem... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #zig | zig | const std = @import("std");
const fs = std.fs;
pub fn main() !void {
const here = fs.cwd();
try here.deleteFile("input.txt");
try here.deleteDir("docs");
const root = try fs.openDirAbsolute("/", .{});
try root.deleteFile("input.txt");
try root.deleteDir("docs");
} | Give a code snippet in #zig
Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Subleq | Subleq | Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of signed integers. These integers... | #PicoLisp | PicoLisp | (de mem (N)
(nth
(quote
15 17 -1 17 -1 -1 16 1 -1 16 3 -1 15 15 0 0 -1
72 101 108 108 111 44 32 119 111 114 108 100 33 10 0 )
(inc N) ) )
(for (IP (mem 0) IP)
(let (A (pop 'IP) B (pop 'IP) C (pop 'IP))
(cond
((lt0 A) (set (mem B) (char)))
((lt0 B) (prin (... | Give a code snippet in #PicoLisp
Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation | Horner's rule for polynomial evaluation | A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\displaystyle ((((0)x+6)x+(-4))x... | #Euler_Math_Toolbox | Euler Math Toolbox |
>function horner (x,v) ...
$ n=cols(v); res=v{n};
$ loop 1 to n-1; res=res*x+v{n-#}; end;
$ return res
$endfunction
>v=[-19,7,-4,6]
[ -19 7 -4 6 ]
>horner(2,v) // test Horner
27
>evalpoly(2,v) // built-in Horner
27
>horner(I,v) // complex values
-15+1i
>horner(1±0.05,v) // interval values
~-10.9,-9.11~
>fu... | Give a code snippet in #Euler_Math_Toolbox
A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Haversine_formula | Haversine formula |
This page uses content from Wikipedia. The original article was at Haversine formula. 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 haversine formula is an equation important in navigation, g... | #Visual_Basic_.NET | Visual Basic .NET | Imports System.Math
Module Module1
Const deg2rad As Double = PI / 180
Structure AP_Loc
Public IATA_Code As String, Lat As Double, Lon As Double
Public Sub New(ByVal iata_code As String, ByVal lat As Double, ByVal lon As Double)
Me.IATA_Code = iata_code : Me.Lat = lat * deg2rad : Me.Lon = lon *... | Give a code snippet in #Visual_Basic_.NET
This page uses content from Wikipedia. The original article was at Haversine formula. 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 haversine formul... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Enforced_immutability | Enforced immutability | Task
Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
| #PHP | PHP | define("PI", 3.14159265358);
define("MSG", "Hello World"); | Give a code snippet in #PHP
Task
Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stream_merge | Stream merge | 2-stream merge
Read two sorted streams of items from external source (e.g. disk, or network), and write one stream of sorted items to external sink.
Common algorithm: keep 1 buffered item from each source, select minimal of them, write it, fetch another item from that stream from which the written item was.
N-strea... | #D | D | import std.range.primitives;
import std.stdio;
// An output range for writing the elements of the example ranges
struct OutputWriter {
void put(E)(E e) if (!isInputRange!E) {
stdout.write(e);
}
}
void main() {
import std.range : only;
merge2(OutputWriter(), only(1,3,5,7), only(2,4,6,8));
... | Give a code snippet in #D
2-stream merge
Read two sorted streams of items from external source (e.g. disk, or network), and write one stream of sorted items to external sink.
Common algorithm: keep 1 buffered item from each source, select minimal of them, write it, fetch another item from that stream from which the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #MATLAB_.2F_Octave | MATLAB / Octave | % Demonstrate how to assign an empty string to a variable.
str = '';
% Demonstrate how to check that a string is empty.
isempty(str)
(length(str)==0)
% Demonstrate how to check that a string is not empty.
~isempty(str)
(length(str)>0) | Give a code snippet in #MATLAB_.2F_Octave
Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not e... | 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... | #BQN | BQN | Join ← {a 𝕊 b‿c: b∾a∾a∾c}
(function block)
":" Join "Rosetta"‿"Code"
"Rosetta::Code" | Give a code snippet in #BQN
Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Topic_variable | Topic variable | Several programming languages offer syntax shortcuts to deal with the notion of "current" or "topic" variable.
A topic variable is a special variable with a very short name which can also often be omitted.
Demonstrate the utilization and behaviour of the topic variable within the language and explain or demonstrate h... | #J | J | example=: *:, %: NB. *: is square, %: is square root
example 3
9 1.73205 | Give a code snippet in #J
Several programming languages offer syntax shortcuts to deal with the notion of "current" or "topic" variable.
A topic variable is a special variable with a very short name which can also often be omitted.
Demonstrate the utilization and behaviour of the topic variable within the language a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ISBN13_check_digit | ISBN13 check digit | Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
978-1734314502 (good)
... | #Kotlin | Kotlin |
fun isValidISBN13(text: String): Boolean {
val isbn = text.replace(Regex("[- ]"), "")
return isbn.length == 13 && isbn.map { it - '0' }
.mapIndexed { index, value -> when (index % 2) { 0 -> value else -> 3 * value } }
.sum() % 10 == 0
}
| Give a code snippet in #Kotlin
Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_literals,_with_continuations | Long literals, with continuations | This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The literal is to be in the form ... | #Phix | Phix | constant last_updated = "March 24th, 2020",
elements_text = `
hydrogen helium lithium beryllium
boron carbon nitrogen oxygen
fluorine neon sodium magnesium
aluminum silicon phosphorous sulfur
chlorine argon potassium calc... | Give a code snippet in #Phix
This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
... | #EchoLisp | EchoLisp |
(lib 'list)
(lib 'matrix)
;; adapted from Racket
(define (permanent M)
(let (( n (matrix-row-num M)))
(for/sum ([σ (in-permutations n)])
(for/product ([i n] [σi σ])
(array-ref M i σi)))))
;; output
(define A (list->array '(1 2 3 4) 2 2))
(array-print A)
1 2
3 4
(determinant A) → ... | Give a code snippet in #EchoLisp
For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
whil... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sudoku | Sudoku | Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| #Swift | Swift | import Foundation
typealias SodukuPuzzle = [[Int]]
class Soduku {
let mBoardSize:Int!
let mBoxSize:Int!
var mBoard:SodukuPuzzle!
var mRowSubset:[[Bool]]!
var mColSubset:[[Bool]]!
var mBoxSubset:[[Bool]]!
init(board:SodukuPuzzle) {
mBoard = board
mBoardSize = board.count... | Give a code snippet in #Swift
Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| 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... | #Wren | Wren | import "io" for Stdout
import "timer" for Timer
var ESC = "\u001b"
var a = "|/-\\"
System.write("%(ESC)[?25l") // hide the cursor
var start = System.clock
var asleep = 0
while (true) {
for (i in 0..3) {
System.write("%(ESC)[2J") // clear terminal
System.write("%(ESC)[0;0H") // place... | Give a code snippet in #Wren
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 p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #Rust | Rust | pub struct CumulativeStandardDeviation {
n: f64,
sum: f64,
sum_sq: f64
}
impl CumulativeStandardDeviation {
pub fn new() -> Self {
CumulativeStandardDeviation {
n: 0.,
sum: 0.,
sum_sq: 0.
}
}
fn push(&mut self, x: f64) -> f64 {
self... | Give a code snippet in #Rust
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the functi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #Euphoria | Euphoria |
function s( atom x )
return 1 / power( x, 2 )
end function
function sum( atom low, atom high )
atom ret = 0.0
for i = low to high do
ret = ret + s( i )
end for
return ret
end function
printf( 1, "%.15f\n", sum( 1, 1000 ) ) | Give a code snippet in #Euphoria
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiple_regression | Multiple regression | Task
Given a set of data vectors in the following format:
y
=
{
y
1
,
y
2
,
.
.
.
,
... | #Python | Python | import numpy as np
height = [1.47, 1.50, 1.52, 1.55, 1.57, 1.60, 1.63,
1.65, 1.68, 1.70, 1.73, 1.75, 1.78, 1.80, 1.83]
weight = [52.21, 53.12, 54.48, 55.84, 57.20, 58.57, 59.93,
61.29, 63.11, 64.47, 66.28, 68.10, 69.92, 72.19, 74.46]
X = np.mat(height**np.arange(3)[:, None])
y = np.mat(weight)
print(y * X... | Give a code snippet in #Python
Task
Given a set of data vectors in the following format:
y
=
{
y
1
,
y
2
,
.
.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Babel | Babel | strrev: { str2ar ar2ls reverse ls2lf ar2str } | Give a code snippet in #Babel
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
... | #Lasso | Lasso | stdoutnl('Sleeping...')
sleep(5000) // Sleep 5 seconds
stdoutnl('Awake!') | Give a code snippet in #Lasso
Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Almost_prime | Almost prime | A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, where
k
=
2
{\displaystyl... | #Fortran | Fortran |
program almost_prime
use iso_fortran_env, only: output_unit
implicit none
integer :: i, c, k
do k = 1, 5
write(output_unit,'(A3,x,I0,x,A1,x)', advance="no") "k =", k, ":"
i = 2
c = 0
do
if (c >= 10) exit
if (kprime(i, k)) then
... | Give a code snippet in #Fortran
A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Van_Eck_sequence | Van Eck sequence | The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured previously.
Example
Using ... | #Ada | Ada | with Ada.Text_IO;
procedure Van_Eck_Sequence is
Sequence : array (Natural range 1 .. 1_000) of Natural;
procedure Calculate_Sequence is
begin
Sequence (Sequence'First) := 0;
for Index in Sequence'First .. Sequence'Last - 1 loop
Sequence (Index + 1) := 0;
for I in reverse Seq... | Give a code snippet in #Ada
The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Runtime_evaluation | Runtime evaluation | Task
Demonstrate a language's ability for programs to execute code written in the language provided at runtime.
Show what kind of program fragments are permitted (e.g. expressions vs. statements), and how to get values in and out (e.g. environments, arguments, return values), if applicable what lexical/static environ... | #HicEst | HicEst | value = XEQ( " temp = 1 + 2 + 3 ") ! value is assigned 6
! temp is undefined outside XEQ, if it was not defined before.
XEQ(" WRITE(Messagebox) 'Hello World !' ")
OPEN(FIle="my_file.txt")
READ(FIle="my_file.txt", Row=6) string
XEQ( string ) ! executes row 6 of my_file.txt | Give a code snippet in #HicEst
Task
Demonstrate a language's ability for programs to execute code written in the language provided at runtime.
Show what kind of program fragments are permitted (e.g. expressions vs. statements), and how to get values in and out (e.g. environments, arguments, return values), if applic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
... | #Haskell | Haskell | import Control.Concurrent
main = do seconds <- readLn
putStrLn "Sleeping..."
threadDelay $ round $ seconds * 1000000
putStrLn "Awake!" | Give a code snippet in #Haskell
Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Barnsley_fern | Barnsley fern |
A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS).
Task
Create this fractal fern, using the following transformations:
ƒ1 (chosen 1% of the time)
xn + 1 = 0
yn + 1 = 0.16 yn
ƒ2 (chosen 85% of the time)
... | #Applesoft_BASIC | Applesoft BASIC | 100 LET YY(1) = .16
110 XX(2) = .85:XY(2) = .04
120 YX(2) = - .04:YY(2) = .85
130 LET Y(2) = 1.6
140 XX(3) = .20:XY(3) = - .26
150 YX(3) = .23:YY(3) = .22
160 LET Y(3) = 1.6
170 XX(4) = - .15:XY(4) = .28
180 YX(4) = .26:YY(4) = .24
190 LET Y(4) = .44
200 HGR :I = PEEK (49234)
210 HC... | Give a code snippet in #Applesoft_BASIC
A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS).
Task
Create this fractal fern, using the following transformations:
ƒ1 (chosen 1% of the time)
xn + 1 = 0
yn + 1 =... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an ov... | #Ruby | Ruby | class Numeric
def pow(m)
raise TypeError, "exponent must be an integer: #{m}" unless m.is_a? Integer
puts "pow!!"
Array.new(m, self).reduce(1, :*)
end
end
p 5.pow(3)
p 5.5.pow(3)
p 5.pow(3.1) | Give a code snippet in #Ruby
Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or proc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primorial_numbers | Primorial numbers | Primorial numbers are those formed by multiplying successive prime numbers.
The primorial number series is:
primorial(0) = 1 (by definition)
primorial(1) = 2 (2)
primorial(2) = 6 (2×3)
primorial(3) = 30 (2×3×5)
primorial(4) = 210 (2×3×5×... | #Sidef | Sidef | say (
'First ten primorials: ',
{|i| pn_primorial(i) }.map(^10).join(', ')
)
{ |i|
say ("primorial(10^#{i}) has " + pn_primorial(10**i).len + ' digits')
} << 1..6 | Give a code snippet in #Sidef
Primorial numbers are those formed by multiplying successive prime numbers.
The primorial number series is:
primorial(0) = 1 (by definition)
primorial(1) = 2 (2)
primorial(2) = 6 (2×3)
primorial(3) = 30 (2×3×5)
primo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sailors,_coconuts_and_a_monkey_problem | Sailors, coconuts and a monkey problem | Five sailors are shipwrecked on an island and collect a large pile of coconuts during the day.
That night the first sailor wakes up and decides to take his first share early so tries to divide the pile of coconuts equally into five piles but finds that there is one coconut left over, so he tosses it to a monkey and th... | #Bc | Bc | define coconuts(sailors, monkeys) {
print "coconuts(", sailors, ", ", monkeys, ") = "
if (sailors < 2 || monkeys < 1 || sailors <= monkeys) {
return 0
}
blue_cocos = sailors-1
pow_bc = blue_cocos^sailors
x_cocos = pow_bc
while ((x_cocos-blue_cocos)%sailors || (x_cocos-blue_cocos)/sailors < 1) {
x_cocos += po... | Give a code snippet in #Bc
Five sailors are shipwrecked on an island and collect a large pile of coconuts during the day.
That night the first sailor wakes up and decides to take his first share early so tries to divide the pile of coconuts equally into five piles but finds that there is one coconut left over, so he ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/The_Twelve_Days_of_Christmas | The Twelve Days of Christmas | Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:
Metrics
Array length
Stri... | #Snobol | Snobol | DAYS = ARRAY('12')
DAYS<1> = 'first'
DAYS<2> = 'second'
DAYS<3> = 'third'
DAYS<4> = 'fourth'
DAYS<5> = 'fifth'
DAYS<6> = 'sixth'
DAYS<7> = 'seventh'
DAYS<8> = 'eighth'
DAYS<9> = 'ninth'
DAYS<10> = 'tenth'
DAYS<11> = 'eleventh'
DAYS<12> = 'twelfth'
GIFTS = ARRAY('12')
GIFTS<1> = 'A partridge in a pear t... | Give a code snippet in #Snobol
Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operatio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Y_combinator | Y combinator | In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions.
This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat... | #Kitten | Kitten | define y<S..., T...> (S..., (S..., (S... -> T...) -> T...) -> T...):
-> f; { f y } f call
define fac (Int32, (Int32 -> Int32) -> Int32):
-> x, rec;
if (x <= 1) { 1 } else { (x - 1) rec call * x }
define fib (Int32, (Int32 -> Int32) -> Int32):
-> x, rec;
if (x <= 2):
1
else:
(x - 1) rec call -> a... | Give a code snippet in #Kitten
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions.
This rules out the usual definition of a recursive function wherein a function is associated with the state of a v... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #REBOL | REBOL | rebol [
Title: "Regular Expression Matching"
URL: http://rosettacode.org/wiki/Regular_expression_matching
]
string: "This is a string."
; REBOL doesn't use a conventional Perl-compatible regular expression
; syntax. Instead, it uses a variant Parsing Expression Grammar with
; the 'parse' function. It's also not l... | Give a code snippet in #REBOL
Task
match a string against a regular expression
substitute part of a string using a regular expression
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_smallest_number_greater_than_previous_term_with_exactly_n_divisors | Sequence: smallest number greater than previous term with exactly n divisors | Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A069654
Related tasks
Sequence: smallest number with exactly n divisors
Sequence: nth ... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | res = {#, DivisorSigma[0, #]} & /@ Range[100000];
highest = 0;
filter = {};
Do[
If[r[[2]] == highest + 1,
AppendTo[filter, r[[1]]];
highest = r[[2]]
]
,
{r, res}
]
Take[filter, 15] | Give a code snippet in #Mathematica_.2F_Wolfram_Language
Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A069654
Related tasks
Sequenc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Carmichael_3_strong_pseudoprimes | Carmichael 3 strong pseudoprimes | A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it.
The Miller Rabin Test uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this.
The purpose of this task is to investigate such numbers using a met... | #ALGOL_68 | ALGOL 68 | # sieve of Eratosthene: sets s[i] to TRUE if i is prime, FALSE otherwise #
PROC sieve = ( REF[]BOOL s )VOID:
BEGIN
# start with everything flagged as prime #
FOR i TO UPB s DO s[ i ] := TRUE OD;
# sieve out the non-primes ... | Give a code snippet in #ALGOL_68
A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it.
The Miller Rabin Test uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this.
The purpose of this task is to in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_elements_below_main_diagonal_of_matrix | Sum of elements below main diagonal of matrix | Task
Find and display the sum of elements that are below the main diagonal of a matrix.
The matrix should be a square matrix.
─── Matrix to be used: ───
[[1,3,7,8,10],
[2,4,16,14,4],
[3,1,9,18,11],
[12,14,17,18,20],
[7,1,3,9,5]]
| #AWK | AWK |
# syntax: GAWK -f SUM_OF_ELEMENTS_BELOW_MAIN_DIAGONAL_OF_MATRIX.AWK
BEGIN {
arr1[++n] = "1,3,7,8,10"
arr1[++n] = "2,4,16,14,4"
arr1[++n] = "3,1,9,18,11"
arr1[++n] = "12,14,17,18,20"
arr1[++n] = "7,1,3,9,5"
for (i=1; i<=n; i++) {
x = split(arr1[i],arr2,",")
if (x != n) {
pri... | Give a code snippet in #AWK
Task
Find and display the sum of elements that are below the main diagonal of a matrix.
The matrix should be a square matrix.
─── Matrix to be used: ───
[[1,3,7,8,10],
[2,4,16,14,4],
[3,1,9,18,11],
[12,14,17,18,20],
[7,1,3,9,5]]
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Counting_sort | Sorting algorithms/Counting sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | countingSort[list_] := Module[{minElem, maxElem, count, z, number},
minElem = Min[list]; maxElem = Max[list];
count = ConstantArray[0, (maxElem - minElem + 1)];
For[number = 1, number < Length[list], number++,
count[[number - minElem + 1]] = count[[number - minElem + 1]] + 1;] ;
z = 1;
For[i = minElem, i ... | Give a code snippet in #Mathematica.2FWolfram_Language
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #PicoLisp | PicoLisp | (let V (in "input.txt" (till))
(out "output.txt" (prin V)) ) | Give a code snippet in #PicoLisp
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a fil... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Output | XML/Output | Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element.
As an example, calling ... | #Ruby | Ruby | require 'rexml/document'
include REXML
remarks = {
%q(April) => %q(Bubbly: I'm > Tam and <= Emily),
%q(Tam O'Shanter) => %q(Burns: "When chapman billies leave the street ..."),
%q(Emily) => %q(Short & shrift),
}
doc = Document.new
root = doc.add_element("CharacterRemarks")
remarks.each do |n... | Give a code snippet in #Ruby
Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> ele... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #Action.21 | Action! | DEFINE LINES_COUNT="10"
DEFINE COLUMNS_COUNT="20"
DEFINE WORDS_COUNT="100"
DEFINE BUFFER_SIZE="2000"
DEFINE LINE_WIDTH="40"
DEFINE PTR="CARD"
PTR ARRAY lines(LINES_COUNT)
BYTE ARRAY wordStart(WORDS_COUNT)
BYTE ARRAY wordLen(WORDS_COUNT)
BYTE ARRAY firstWordInLine(LINES_COUNT)
BYTE ARRAY wordsInLine(LINES_COUNT)
BYTE ... | Give a code snippet in #Action.21
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Named_parameters | Named parameters | Create a function which takes in a number of arguments which are specified by name rather than (necessarily) position, and show how to call the function. If the language supports reordering the arguments or optionally omitting some of them, note this.
Note:
Named parameters relies on being able to use the names give... | #Factor | Factor |
:: my-named-params ( a b -- c ) a b * ;
| Give a code snippet in #Factor
Create a function which takes in a number of arguments which are specified by name rather than (necessarily) position, and show how to call the function. If the language supports reordering the arguments or optionally omitting some of them, note this.
Note:
Named parameters relies on ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #Excel | Excel | =NOW() | Give a code snippet in #Excel
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_comparison | String 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 |... | #Perl | Perl | use v5.16; # ...for fc(), which does proper Unicode casefolding.
# With older Perl versions you can use lc() as a poor-man's substitute.
sub compare {
my ($a, $b) = @_;
my $A = "'$a'";
my $B = "'$b'";
print "$A and $B are lexically equal.\n" if $a eq $b;
print "$A and $B are not... | Give a code snippet in #Perl
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
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Prime_triangle | Prime triangle | You will require a function f which when given an integer S will return a list of the arrangements of the integers 1 to S such that g1=1 gS=S and generally for n=1 to n=S-1 gn+gn+1 is prime. S=1 is undefined. For S=2 to S=20 print f(S) to form a triangle. Then again for S=2 to S=20 print the number of possible arrangem... | #ALGOL_68 | ALGOL 68 | BEGIN # find solutions to the "Prime Triangle" - a triangle of numbers that sum to primes #
INT max number = 18; # largest number we will consider #
# construct a primesieve and from that a table of pairs of numbers whose sum is prime #
[ 0 : 2 * max number ]BOOL prime;
prime[ 0 ] := prime[ 1 ] := FALSE... | Give a code snippet in #ALGOL_68
You will require a function f which when given an integer S will return a list of the arrangements of the integers 1 to S such that g1=1 gS=S and generally for n=1 to n=S-1 gn+gn+1 is prime. S=1 is undefined. For S=2 to S=20 print f(S) to form a triangle. Then again for S=2 to S=20 pri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat | Repeat | Task
Write a procedure which accepts as arguments another procedure and a positive integer.
The latter procedure is executed a number of times equal to the accepted integer.
| #Gambas | Gambas |
Public Sub Main()
RepeatIt("RepeatableOne", 2)
RepeatIt("RepeatableTwo", 3)
End
'Cannot pass procedure pointer in Gambas; must pass procedure name and use Object.Call()
Public Sub RepeatIt(sDelegateName As String, iCount As Integer)
For iCounter As Integer = 1 To iCount
Object.Call(Me, s... | Give a code snippet in #Gambas
Task
Write a procedure which accepts as arguments another procedure and a positive integer.
The latter procedure is executed a number of times equal to the accepted integer.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_the_coins | Count the coins | There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels and 5 pennies
A nickel and 10 pen... | #Mercury | Mercury | :- module coins.
:- interface.
:- import_module int, io.
:- type coin ---> quarter; dime; nickel; penny.
:- type purse ---> purse(int, int, int, int).
:- pred sum_to(int::in, purse::out) is nondet.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module solutions, list, string.
:- func value(coin... | Give a code snippet in #Mercury
There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels and... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Heapsort | Sorting algorithms/Heapsort |
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
... | #Groovy | Groovy | def makeSwap = { a, i, j = i+1 -> print "."; a[[j,i]] = a[[i,j]] }
def checkSwap = { list, i, j = i+1 -> [(list[i] > list[j])].find{ it }.each { makeSwap(list, i, j) } }
def siftDown = { a, start, end ->
def p = start
while (p*2 < end) {
def c = p*2 + ((p*2 + 1 < end && a[p*2 + 2] > a[p*2 + 1]) ? ... | Give a code snippet in #Groovy
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 s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_year | Long year | Most years have 52 weeks, some have 53, according to ISO8601.
Task
Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
| #Scheme | Scheme | (define (dec31wd year)
(remainder (apply + (map (lambda (d) (quotient year d)) '(1 4 -100 400))) 7))
(define (long? year) (or (= 4 (dec31wd year)) (= 3 (dec31wd (- year 1)))))
(display "Long years between 1800 and 2100:") (newline)
(display (filter long? (iota 300 1800))) | Give a code snippet in #Scheme
Most years have 52 weeks, some have 53, according to ISO8601.
Task
Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Partial_function_application | Partial function application | Partial function application is the ability to take a function of many
parameters and apply arguments to some of the parameters to create a new
function that needs only the application of the remaining arguments to
produce the equivalent of applying all arguments to the original function.
E.g:
Given values v1, v2
... | #Lambdatalk | Lambdatalk |
1) just define function as usual:
{def add {lambda {:a :b :c} {+ :a :b :c}}} -> add
2) and use it:
{add 1 2 3} -> 6
{{add 1} 2 3} -> 6
{{add 1 2} 3} -> 6
{{{add 1} 2} 3} -> 6
3) application:
{def fs {lambda {:f} map :f}}
{def f1 {lambda {:x} {* :x 2}}}
{def f2 {lambda {:x} {pow :x 2}}}
{def fs... | Give a code snippet in #Lambdatalk
Partial function application is the ability to take a function of many
parameters and apply arguments to some of the parameters to create a new
function that needs only the application of the remaining arguments to
produce the equivalent of applying all arguments to the original fu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #Objective-C | Objective-C | NSLog(@"%@", [NSDate date]); | Give a code snippet in #Objective-C
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Elementary_cellular_automaton/Random_Number_Generator | Elementary cellular automaton/Random Number Generator | Rule 30 is considered to be chaotic enough to generate good pseudo-random numbers. As a matter of fact, rule 30 is used by the Mathematica software for its default random number generator.
Steven Wolfram's recommendation for random number generation from rule 30 consists in extracting successive bits in a fixed positi... | #Nim | Nim | const N = 64
template pow2(x: uint): uint = 1u shl x
proc evolve(state: uint; rule: Positive) =
var state = state
for _ in 1..10:
var b = 0u
for q in countdown(7, 0):
let st = state
b = b or (st and 1) shl q
state = 0
for i in 0u..<N:
let t = (st shr (i - 1) or st shl (N ... | Give a code snippet in #Nim
Rule 30 is considered to be chaotic enough to generate good pseudo-random numbers. As a matter of fact, rule 30 is used by the Mathematica software for its default random number generator.
Steven Wolfram's recommendation for random number generation from rule 30 consists in extracting succ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_lines_from_a_file | Remove lines from a file | Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from th... | #AWK | AWK |
# syntax: GAWK -f REMOVE_LINES_FROM_A_FILE.AWK
# show files after lines are removed:
# GAWK "FNR==1{print(FILENAME)};{print(FNR,$0)}" TEST1 TEST2 TEST3
BEGIN {
build_test_data()
remove_lines("TEST0",1,1)
remove_lines("TEST1",3,4)
remove_lines("TEST2",9,3)
remove_lines("TEST3",11,1)
exit(erro... | Give a code snippet in #AWK
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remov... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Smalltalk | Smalltalk | 'asdf' reverse | Give a code snippet in #Smalltalk
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
E... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #zkl | zkl | fcn{self.fcn()}() | Give a code snippet in #zkl
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/ABC_problem | ABC problem | ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet is guaranteed amongst all sid... | #AutoHotkey | AutoHotkey | isWordPossible(blocks, word){
o := {}
loop, parse, blocks, `n, `r
o.Insert(A_LoopField)
loop, parse, word
if !(r := isWordPossible_contains(o, A_LoopField, word))
return 0
return 1
}
isWordPossible_contains(byref o, letter, word){
loop 2 {
for k,v in o
if Instr(v,letter)
{
StringReplace, op, v,%... | Give a code snippet in #AutoHotkey
ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N-queens_problem | N-queens problem |
Solve the eight queens puzzle.
You can extend the problem to solve the puzzle with a board of size NxN.
For the number of solutions for small values of N, see OEIS: A000170.
Related tasks
A* search algorithm
Solve a Hidato puzzle
Solve a Holy Knight's tour
Knight's tour
Peaceful chess queen armie... | #CoffeeScript | CoffeeScript |
# Unlike traditional N-Queens solutions that use recursion, this
# program attempts to more closely model the "human" algorithm.
#
# In this algorithm, the function keeps placing queens on the board
# until there is no longer a safe square. If the 8th queen has been
# placed, the solution is noted. If fewer than 8... | Give a code snippet in #CoffeeScript
Solve the eight queens puzzle.
You can extend the problem to solve the puzzle with a board of size NxN.
For the number of solutions for small values of N, see OEIS: A000170.
Related tasks
A* search algorithm
Solve a Hidato puzzle
Solve a Holy Knight's tour
Kni... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_the_coins | Count the coins | There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels and 5 pennies
A nickel and 10 pen... | #Go | Go | package main
import "fmt"
func main() {
amount := 100
fmt.Println("amount, ways to make change:", amount, countChange(amount))
}
func countChange(amount int) int64 {
return cc(amount, 4)
}
func cc(amount, kindsOfCoins int) int64 {
switch {
case amount == 0:
return 1
case amount <... | Give a code snippet in #Go
There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels and 5 pe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compare_a_list_of_strings | Compare a list of strings | Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false value, which could be used as t... | #C.23 | C# | public static (bool lexicallyEqual, bool strictlyAscending) CompareAListOfStrings(List<string> strings) =>
strings.Count < 2 ? (true, true) :
(
strings.Distinct().Count() < 2,
Enumerable.Range(1, strings.Count - 1).All(i => string.Compare(strings[i-1], strings[i]) < 0)
); | Give a code snippet in #C.23
Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false v... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #PureBasic | PureBasic | ;use last bit method
isOdd = i & 1 ;isOdd is non-zero if i is odd
isEven = i & 1 ! 1 ;isEven is non-zero if i is even
;use modular method
isOdd = i % 2 ;isOdd is non-zero if i is odd
isEven = i % 2 ! 1 ;isEven is non-zero if i is even | Give a code snippet in #PureBasic
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Recaman%27s_sequence | Recaman's sequence | The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the... | #Julia | Julia | function recaman()
a = Vector{Int}([0])
used = Dict{Int, Bool}(0 => true)
used1000 = Set(0)
founddup = false
termcount = 1
while length(used1000) <= 1000
nextterm = a[termcount] - termcount
if nextterm < 1 || haskey(used, nextterm)
nextterm += termcount + termcount
... | Give a code snippet in #Julia
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Ta... | 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.
... | #XLISP | XLISP | (DO ((I 1 (+ I 1))) ((> I 5))
(DO ((J 0 (+ J 1))) ((= J I))
(DISPLAY "*"))
(NEWLINE)) | Give a code snippet in #XLISP
“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 structu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test | Verify distribution uniformity/Chi-squared test | Task
Write a function to verify that a given distribution of values is uniform by using the
χ
2
{\displaystyle \chi ^{2}}
test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%).
The function should return a boolean that is true if the distribut... | #Go | Go | package main
import (
"fmt"
"math"
)
type ifctn func(float64) float64
func simpson38(f ifctn, a, b float64, n int) float64 {
h := (b - a) / float64(n)
h1 := h / 3
sum := f(a) + f(b)
for j := 3*n - 1; j > 0; j-- {
if j%3 == 0 {
sum += 2 * f(a+h1*float64(j))
} els... | Give a code snippet in #Go
Task
Write a function to verify that a given distribution of values is uniform by using the
χ
2
{\displaystyle \chi ^{2}}
test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%).
The function should return a boolean t... | 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 ... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const proc: main is func
begin
writeln(STD_ERR, "Goodbye, World!");
end func; | Give a code snippet in #Seed7
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/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #Modula-3 | Modula-3 | MODULE StringInt EXPORTS Main;
IMPORT IO, Fmt, Scan;
VAR string: TEXT := "1234";
num: INTEGER := 0;
BEGIN
num := Scan.Int(string);
IO.Put(string & " + 1 = " & Fmt.Int(num + 1) & "\n");
END StringInt. | Give a code snippet in #Modula-3
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newline_omission | Hello world/Newline omission | Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standard error
Hello world/Text
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Print "Goodbye, World!"; '' the trailing semi-colon suppresses the new line
Sleep | Give a code snippet in #FreeBASIC
Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/S... | 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 |... | #C | C | #include <stdio.h>
int main()
{
int a, b;
scanf("%d %d", &a, &b);
if (a < b)
printf("%d is less than %d\n", a, b);
if (a == b)
printf("%d is equal to %d\n", a, b);
if (a > b)
printf("%d is greater than %d\n", a, b);
return 0;
} | Give a code snippet in #C
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
Conc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #CLU | CLU | factorial = proc (n: int) returns (int) signals (negative)
if n<0 then signal negative
elseif n=0 then return(1)
else return(n * factorial(n-1))
end
end factorial
start_up = proc ()
po: stream := stream$primary_output()
for i: int in int$from_to(0, 10) do
fac: int := factorial(i)
... | Give a code snippet in #CLU
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #Prolog | Prolog | mortal(X) :- man(X).
man(socrates). | Give a code snippet in #Prolog
Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #ACL2 | ACL2 | (defun recursion-limit (x)
(if (zp x)
0
(prog2$ (cw "~x0~%" x)
(1+ (recursion-limit (1+ x)))))) | Give a code snippet in #ACL2
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fusc_sequence | Fusc sequence |
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition starts with unity, not zero. Th... | #Swift | Swift | struct FuscSeq: Sequence, IteratorProtocol {
private var arr = [0, 1]
private var i = 0
mutating func next() -> Int? {
defer {
i += 1
}
guard i > 1 else {
return arr[i]
}
switch i & 1 {
case 0:
arr.append(arr[i / 2])
case 1:
arr.append(arr[(i - 1) / 2] + a... | Give a code snippet in #Swift
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition st... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #MIPS_Assembly | MIPS Assembly |
# First, it gets the length of the original string
# Then, it allocates memory from the copy
# Then it copies the pointer to the original string, and adds the strlen
# subtract 1, then that new pointer is at the last char.
# while(strlen)
# copy char
# decrement strlen
# decrement source pointer
# ... | Give a code snippet in #MIPS_Assembly
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a strin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Output | Non-decimal radices/Output | Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routines of your programming langu... | #XPL0 | XPL0 | include c:\cxpl\codes;
int N;
[N:= 2;
repeat HexOut(0, N); Text(0, " ");
IntOut(0, N); CrLf(0);
N:= N*N;
until N=0;
] | Give a code snippet in #XPL0
Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard rout... | christopher/rosetta-code |
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