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 |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #sed | sed | #!/usr/bin/sed -f
G
:loop
s/^[[:space:]]*\([^[:space:]][^[:space:]]*\)\(.*\n\)/\2 \1/
t loop
s/^[[:space:]]*// |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #VBScript | VBScript |
option explicit
function rot13(a)
dim b,n1,n,i
b=""
for i=1 to len(a)
n=asc(mid(a,i,1))
if n>=65 and n<= 91 then
n1=(((n-65)+13)mod 26)+65
elseif n>=97 and n<= 123 then
n1=(((n-97)+13)mod 26)+97
else
n1=n
end if
b=b & chr(n1)
next
rot13=b
end function
con... |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Ursala | Ursala | #import nat
roman =
-+
'IIII'%='IV'+ 'VIIII'%='IX'+ 'XXXX'%='XL'+ 'LXXXX'%='XC'+ 'CCCC'%='CD'+ 'DCCCC'%='CM',
~&plrDlSPSL/'MDCLXVI'+ iota*+ +^|(^|C/~&,\/division)@rlX=>~&iNC <1000,500,100,50,10,5>+- |
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... | #LFE | LFE |
(string:copies '"ha" 5)
|
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... | #Liberty_BASIC | Liberty BASIC | a$ ="ha "
print StringRepeat$( a$, 5)
end
function StringRepeat$( in$, n)
o$ =""
for i =1 to n
o$ =o$ +in$
next i
StringRepeat$ =o$
end function |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Ursa | Ursa | def getstrs (int n)
decl string<> input
while (> n 0)
out ": " console
append (in string console) input
dec n
end while
return input
end getstrs
decl int amount
out "how many strings do you want to enter? " console
set amount (in int ... |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #VBA | VBA |
Type Contact
Name As String
firstname As String
Age As Byte
End Type
Function SetContact(N As String, Fn As String, A As Byte) As Contact
SetContact.Name = N
SetContact.firstname = Fn
SetContact.Age = A
End Function
'For use :
Sub Test_SetContact()
Dim Cont As Contact
Cont = SetConta... |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #Inform_7 | Inform 7 | To decide which list of Ks is (L - list of values of kind K) without duplicates:
let result be a list of Ks;
repeat with X running through L:
add X to result, if absent;
decide on result. |
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... | #Perl | Perl | sub rref
{our @m; local *m = shift;
@m or return;
my ($lead, $rows, $cols) = (0, scalar(@m), scalar(@{$m[0]}));
foreach my $r (0 .. $rows - 1)
{$lead < $cols or return;
my $i = $r;
until ($m[$i][$lead])
{++$i == $rows or next;
$i = $r;
++$lead == $cols and return... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Logo | Logo | make "e exp 1
make "pi 2*(RADARCTAN 0 1)
sqrt :x
ln :x
exp :x
; there is no standard abs, floor, or ceiling; only INT and ROUND.
power :x :y |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Logtalk | Logtalk |
:- object(constants_and_functions).
:- public(show/0).
show :-
write('e = '), E is e, write(E), nl,
write('pi = '), PI is pi, write(PI), nl,
write('sqrt(2) = '), SQRT is sqrt(2), write(SQRT), nl,
% only base e logorithm is avaialable as a standard built-in function
wr... |
http://rosettacode.org/wiki/Remove_lines_from_a_file | Remove lines from a file | Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from th... | #Tcl | Tcl | proc removeLines {fileName startLine count} {
# Work out range to remove
set from [expr {$startLine - 1}]
set to [expr {$startLine + $count - 2}]
# Read the lines
set f [open $fileName]
set lines [split [read $f] "\n"]
close $f
# Write the lines back out, without removed range
set f ... |
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... | #Neko | Neko | /**
Read entire file
Tectonics:
nekoc read-entire-file.neko
neko read-entire-file
*/
var file_contents = $loader.loadprim("std@file_contents", 1);
try {
var entire_file = file_contents("read-entire-file.neko");
$print("Read: ", $ssize(entire_file), " bytes\n");
} catch e {
$print("Exception: ", e, "\n... |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
parse arg inFileName .
if inFileName = '' | inFileName = '.' then inFileName = './data/dwarfs.json'
fileContents = slurp(inFileName)
say fileContents
return
-- Slurp a file and return contents as a Rexx string
method slurp(inFileName) ... |
http://rosettacode.org/wiki/Rep-string | Rep-string | Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For e... | #Yabasic | Yabasic | data "1001110011", "1110111011", "0010010010", "1010101010", "1111111111", "0100101101", "0100100", "101", "11", "00", "1", ""
sub rep$(c$, n)
local r$, i
for i = 1 to n
r$ = r$ + c$
next
return r$
end sub
do
read p$ : if p$ = "" break
b$ = "" : l = len(p$) : m = int(l / 2)
... |
http://rosettacode.org/wiki/Rep-string | Rep-string | Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For e... | #zkl | zkl | fcn repString(s){
foreach n in ([s.len()/2+1..1,-1]){
Walker.cycle(s[0,n]).pump(s.len(),String) :
if(_==s and n*2<=s.len()) return(n);
}
return(False)
} |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Sidef | Sidef | var str = "I am a string";
if (str =~ /string$/) {
print "Ends with 'string'\n";
} |
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
| #Slate | Slate |
'http://slatelanguage.org/test/page?query' =~ '^(([^:/?#]+)\\:)?(//([^/?#]*))?([^?#]*)(\\?([^#]*))?(#(.*))?'.
" ==> {'http:'. 'http'. '//slatelanguage.org'. 'slatelanguage.org'. '/test/page'. '?query'. 'query'. Nil} "
|
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
... | #EGL | EGL | function reverse( str string ) returns( string )
result string;
for ( i int from StrLib.characterLen( str ) to 1 decrement by 1 )
result ::= str[i:i];
end
return( result );
end |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #Yorick | Yorick | rename, "input.txt", "output.txt";
rename, "/input.txt", "/output.txt";
rename, "docs", "mydocs";
rename, "/docs", "/mydocs"; |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #zkl | zkl | ls -ld input.txt docs output.txt mydocs
ls: cannot access 'output.txt': No such file or directory
ls: cannot access 'mydocs': No such file or directory
drwxr-xr-x 2 craigd craigd 4096 Aug 10 16:24 docs
-rw-r--r-- 1 craigd craigd 0 Aug 10 16:24 input.txt
$ zkl
zkl: File.rename("input.txt","output.txt")
True
zkl: File... |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const array string: lines is [] (
"---------- Ice and Fire ------------",
"",
"fire, in end will world the say Some",
"ice. in say Some",
"desire of tasted I've what From",
"fire. favor who those with hold I",
"",
"... elided paragraph last ...",
"",
"... |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #SenseTalk | SenseTalk | set poem to {{
---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------
}}
repeat with each line in poem
put (each word of it) reversed joined b... |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #Wart | Wart | def (rot13 s)
(as string
(map rot13
(as list s)))
Alphabet <- "abcdefghijklmnopqrstuvwxyz"
def (rot13 c) :case (and string?.c len.c=1)
if ("a" <= c <= "z")
let idx (pos c Alphabet)
Alphabet (idx+13 % 26)
("A" <= c <= "Z")
(downcase.c -> rot13 -> upcase)
:else
... |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Vala | Vala | string to_roman(int n)
requires (n > 0 && n < 5000)
{
const int[] weights = {1000, 900, 500, 400, 100, 90,
50, 40, 10, 9, 5, 4, 1};
const string[] symbols = {"M","CM","D","CD","C","XC","L",
"XL","X","IX","V","IV","I"};
var roman = "", count = 0;
foreach ... |
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... | #Lingo | Lingo | on rep (str, n)
res = ""
repeat with i = 1 to n
put str after res
end repeat
return res
end |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Visual_FoxPro | Visual FoxPro |
*!* Return multiple values from a function
*!* The simplest way is to pass the parameters by reference
*!* either by SET UDFPARMS TO REFERENCE, or prefix the variables with @.
LOCAL a, b
a = 5
b = 6
? "Sum =", AddUp(@a, @b) && Displays 11
? "a =", a, "b =", b && Displays 4, 5
? "Sum =", AddUp(@a, @b) && ... |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Wren | Wren | var splitName = Fn.new { |fullName| fullName.split(" ") }
var names = splitName.call("George Bernard Shaw")
System.print("First name: %(names[0]), middle name: %(names[1]) and surname: %(names[2]).") |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #IS-BASIC | IS-BASIC | 100 PROGRAM "RemoveDu.bas"
110 RANDOMIZE
120 NUMERIC ARR(1 TO 20),TOP
130 LET TOP=FILL(ARR)
140 CALL WRITE(ARR,TOP)
150 LET TOP=REMOVE(ARR)
160 CALL WRITE(ARR,TOP)
170 DEF WRITE(REF A,N)
180 FOR I=1 TO N
190 PRINT A(I);
200 NEXT
210 PRINT
220 END DEF
230 DEF FILL(REF A)
240 LET FILL=UBOUND(A):LET A(LBOUND(A... |
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... | #Phix | Phix | with javascript_semantics
function ToReducedRowEchelonForm(sequence M)
integer lead = 1,
rowCount = length(M),
columnCount = length(M[1]),
i
for r=1 to rowCount do
if lead>=columnCount then exit end if
i = r
while M[i][lead]=0 do
i += 1
if i=ro... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Lua | Lua | math.exp(1)
math.pi
math.sqrt(x)
math.log(x)
math.log10(x)
math.exp(x)
math.abs(x)
math.floor(x)
math.ceil(x)
x^y |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #M2000_Interpreter | M2000 Interpreter |
Module Checkit {
Def exp(x)= 2.71828182845905^x
Print Ln(exp(1))==1
Print Log(10^5)==5
Print Sgn(-5)=-1
Print Abs(-2.10#)=2.1#
Def exptype$(x)=type$(x)
Print exptype$(Abs(-2.1#))="Currency"
Print exptype$(Abs(-2.1~))="Single"
Print exptype$(Abs(-2.1@))="Decimal"
... |
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... | #TUSCRIPT | TUSCRIPT |
$$! input=testfile,begnr=3,endnr=4
$$ MODE TUSCRIPT
- CREATE inputfile
ERROR/STOP CREATE (input,FDF-o,-std-)
FILE/ERASE $input
LOOP n=1,9
content=CONCAT ("line",n)
DATA {content}
ENDLOOP
ENDFILE
- CREATE outputfile
output="outputfile"
ERROR/STOP CREATE (output,fdf-o,-std-)
ACCESS q: READ/RECORDS/utf8 $input ... |
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... | #NewLISP | NewLISP | (read-file "filename") |
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
| #Smalltalk | Smalltalk | |re s s1|
re := Regex fromString: '[a-z]+ing'.
s := 'this is a matching string'.
s1 := 'this does not match'.
(s =~ re)
ifMatched: [ :b |
b match displayNl
].
(s1 =~ re)
ifMatched: [ :b |
'Strangely matched!' displayNl
]
ifNotMatched: [
'no match!' displayNl
].
(s replacingRegex: re with: 'modified') displ... |
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
| #SNOBOL4 | SNOBOL4 | label subject pattern = object :(goto) |
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
... | #Eiffel | Eiffel | class
APPLICATION
create
make
feature
make
-- Demonstrate string reversal.
do
my_string := "Hello World!"
my_string.mirror
print (my_string)
end
my_string: STRING
-- Used for reversal
end |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Sidef | Sidef | DATA.each{|line| line.words.reverse.join(" ").say};
__DATA__
---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert ----------------------- |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #Whenever | Whenever |
1 2#read()-N(2);
2 2;
3 defer(1 || N(2) > 90 || N(2) < 65) 5#65-N(5);
4 defer(1 || N(2) > 122 || N(2) < 97) 5#97-N(5);
5 5;
6 defer(3 && 4) put(U(((N(2) - N(5) + 13) % 26) + N(5)));
7 defer(1 || N(2) > 64 || N(2) == 0) put(U(N(2)));
8 again(8) defer(6 && 7) 1,-6#N(6)-1,-7#N(7)-1,-3#N(3)-1,-4#N(4)-1;
9 defer(1 || N(2)... |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #VBA | VBA | Private Function roman(n As Integer) As String
roman = WorksheetFunction.roman(n)
End Function
Public Sub main()
s = [{10, 2016, 800, 2769, 1666, 476, 1453}]
For Each x In s
Debug.Print roman(CInt(x)); " ";
Next x
End Sub |
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... | #LiveCode | LiveCode | on mouseUp
put repeatString("ha", 5)
end mouseUp
function repeatString str n
repeat n times
put str after t
end repeat
return t
end repeatString |
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... | #Logo | Logo | to copies :n :thing [:acc "||]
if :n = 0 [output :acc]
output (copies :n-1 :thing combine :acc :thing)
end |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
proc Rect2Polar(X,Y,A,D); \Return two polar coordinate values
real X,Y,A,D;
[A(0):= ATan2(Y,X);
D(0):= Sqrt(X*X+Y*Y);
]; \Rect2Polar
real Ang, Dist;
[Rect2Polar(4.0, 3.0, @Ang, @Dist); \("@" is a new feature similar to 'addr')
RlOut(0, Ang);
Rl... |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Z80_Assembly | Z80 Assembly | foo:
ld hl,&ABCD
ld bc,&FFFF
ret |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #J | J | ~. 4 3 2 8 0 1 9 5 1 7 6 3 9 9 4 2 1 5 3 2
4 3 2 8 0 1 9 5 7 6
~. 'chthonic eleemosynary paronomasiac'
chtoni elmsyarp |
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... | #PHP | PHP | <?php
function rref($matrix)
{
$lead = 0;
$rowCount = count($matrix);
if ($rowCount == 0)
return $matrix;
$columnCount = 0;
if (isset($matrix[0])) {
$columnCount = count($matrix[0]);
}
for ($r = 0; $r < $rowCount; $r++) {
if ($lead >= $columnCount)
break... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Maple | Maple | > abs(ceil(floor(ln(exp(1)^sqrt(exp(Pi*I)+1)))));
0 |
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... | #UNIX_Shell | UNIX Shell | #!/bin/sh
error() {
echo >&2 "$0: $*"
exit 1
}
[ $# -ne 3 ] && error "Incorrect number of parameters"
file=$1
start=$2
count=$3
end=`expr $start + $count - 1`
[ -f "$file" ] || error "$file does not exist"
sed "$start,${end}d" "$file" >/tmp/$$ && mv /tmp/$$ "$file"
|
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #Nim | Nim | readFile(filename) |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #Objeck | Objeck |
string := FileReader->ReadFile("in.txt");
|
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Standard_ML | Standard ML | CM.make "$/regexp-lib.cm";
structure RE = RegExpFn (
structure P = AwkSyntax
structure E = BackTrackEngine);
val re = RE.compileString "string$";
val string = "I am a string";
case StringCvt.scanString (RE.find re) string
of NONE => print "match failed\n"
| SOME match =>
let
val {pos, len} ... |
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
| #Stata | Stata | scalar s="ars longa vita brevis"
* is there a vowel?
di regexm(s,"[aeiou]")
* replace the first vowel with "?"
di regexr(s,"[aeiou]","?") |
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
... | #Ela | Ela | reverse_string str = rev len str
where len = length str
rev 0 str = ""
rev n str = toString (str : nn) +> rev nn str
where nn = n - 1
reverse_string "Hello" |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Smalltalk | Smalltalk |
poem := '---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I''ve what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------'.
(poem lines collect: [ :line | ((line splitOn: ' ') reverse) joinUsing: ' ... |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Sparkling | Sparkling | let lines = split("---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------", "\n");
foreach(lines, function(idx, line) {
let words = split(line... |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #Whitespace | Whitespace |
... |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Vedit_macro_language | Vedit macro language | // Main program for testing the function
//
do {
#1 = Get_Num("Number to convert: ", STATLINE)
Call("NUM_TO_ROMAN")
Num_Type(#1, NOCR) Message(" = ") Reg_Type(1) Type_Newline
} while (Reg_Size(1))
Return
// Convert numeric value into Roman number
// #1 = number to convert; on return: T-reg(1) = Roman num... |
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... | #Lua | Lua | function repeats(s, n) return n > 0 and s .. repeats(s, n-1) or "" end |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #zkl | zkl | fcn f{return(1,2,"three")}
a,b,c:=f() // a==1, b==2, c=="three" |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #Java | Java | import java.util.*;
class Test {
public static void main(String[] args) {
Object[] data = {1, 1, 2, 2, 3, 3, 3, "a", "a", "b", "b", "c", "d"};
Set<Object> uniqueSet = new HashSet<Object>(Arrays.asList(data));
for (Object o : uniqueSet)
System.out.printf("%s ", o);
}
} |
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... | #PicoLisp | PicoLisp | (de reducedRowEchelonForm (Mat)
(let (Lead 1 Cols (length (car Mat)))
(for (X Mat X (cdr X))
(NIL
(loop
(T (seek '((R) (n0 (get R 1 Lead))) X)
@ )
(T (> (inc 'Lead) Cols)) ) )
(xchg @ X)
(let D (get X 1 Lead)
(m... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | E
Pi
Sqrt[x]
Log[x]
Log[b,x]
Exp[x]
Abs[x]
Floor[x]
Ceiling[x]
Power[x, y] |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #MATLAB_.2F_Octave | MATLAB / Octave | exp(1) % e
pi % pi
sqrt(x) % square root
log(x) % natural logarithm
log2(x) % logarithm base 2
log10(x) % logarithm base 10
exp(x) % exponential
abs(-x) % absolute value
floor(x) % floor
ceil(x) % ceiling
x^y % power |
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... | #VBA | VBA | Option Explicit
Sub Main()
'See Output #1
RemoveLines "C:\Users\" & Environ("username") & "\Desktop\foobar.txt", 11, 5
'See Output #2
RemoveLines "C:\Users\" & Environ("username") & "\Desktop\foobar.txt", 8, 5
'See Output #3
RemoveLines "C:\Users\" & Environ("username") & "\Desktop\foobar.txt", 3, 5... |
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... | #Objective-C | Objective-C |
/*** 0. PREPARATION */
// We need a text file to read; let's redirect a C string to a new file
// using the shell by way of the stdlib system() function.
system ("echo \"Hello, World!\" > ~/HelloRosetta");
/*** 1. THE TASK */
// Instantiate an NSString which describes the filesys... |
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... | #OCaml | OCaml | let load_file f =
let ic = open_in f in
let n = in_channel_length ic in
let s = Bytes.create n in
really_input ic s 0 n;
close_in ic;
(s) |
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
| #Swift | Swift | import Foundation
let str = "I am a string"
if let range = str.rangeOfString("string$", options: .RegularExpressionSearch) {
println("Ends with 'string'")
} |
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
| #Tcl | Tcl | set theString "I am a string"
if {[regexp -- {string$} $theString]} {
puts "Ends with 'string'"
}
if {![regexp -- {^You} $theString]} {
puts "Does not start with 'You'"
} |
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
... | #Elena | Elena | import system'routines;
import extensions;
import extensions'text;
extension extension
{
reversedLiteral()
= self.toArray().sequenceReverse().summarize(new StringWriter());
}
public program()
{
console.printLine("Hello World".reversedLiteral())
} |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Standard_ML | Standard ML | val lines = [
" ---------- Ice and Fire ------------ ",
" ",
" fire, in end will world the say Some ",
" ice. in say Some ",
" desire of tasted I've what From ",
" fire. favor who those with hold I ",
" "... |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Swift | Swift | import Foundation
// convenience extension for better clarity
extension String {
var lines: [String] {
get {
return self.componentsSeparatedByCharactersInSet(NSCharacterSet.newlineCharacterSet())
}
}
var words: [String] {
get {
return self.componentsSeparate... |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #Wren | Wren | var rot13 = Fn.new { |s|
var bytes = s.bytes.toList
for (i in 0...bytes.count) {
var c = bytes[i]
if ((c >= 65 && c <= 77) || (c >= 97 && c <= 109)) {
bytes[i] = c + 13
} else if ((c >= 78 && c <= 90) || (c >= 110 && c <= 122)) {
bytes[i] = c - 13
}
}
... |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Visual_Basic | Visual Basic | Function toRoman(value) As String
Dim arabic As Variant
Dim roman As Variant
arabic = Array(1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1)
roman = Array("M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I")
Dim i As Integer, result As String
For i = 0 To 12
... |
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... | #Maple | Maple |
> use StringTools in
> Repeat( "abc", 10 ); # repeat an arbitrary string
> Fill( "x", 20 ) # repeat a character
> end use;
"abcabcabcabcabcabcabcabcabcabc"
"xxxxxxxxxxxxxxxxxxxx"
|
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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | (* solution 1 *)
rep[n_Integer,s_String]:=Apply[StringJoin,ConstantArray[s,{n}]]
(* solution 2 -- @@ is the infix form of Apply[] *)
rep[n_Integer,s_String]:=StringJoin@@Table[s,{n}]
(* solution 3 -- demonstrating another of the large number of looping constructs available *)
rep[n_Integer,s_String]:=Nest[StringJoin[s,... |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #JavaScript | JavaScript | function unique(ary) {
// concat() with no args is a way to clone an array
var u = ary.concat().sort();
for (var i = 1; i < u.length; ) {
if (u[i-1] === u[i])
u.splice(i,1);
else
i++;
}
return u;
}
var ary = [1, 2, 3, "a", "b", "c", 2, 3, 4, "b", "c", "d", "... |
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... | #Python | Python | def ToReducedRowEchelonForm( M):
if not M: return
lead = 0
rowCount = len(M)
columnCount = len(M[0])
for r in range(rowCount):
if lead >= columnCount:
return
i = r
while M[i][lead] == 0:
i += 1
if i == rowCount:
i = r
... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #MAXScript | MAXScript | e -- Euler's number
pi -- pi
log x -- natural logarithm
log10 x -- log base 10
exp x -- exponantial
abs x -- absolute value
floor x -- floor
ceil x -- ceiling
pow x y -- power |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Mercury | Mercury |
math.pi % Pi.
math.e % Euler's number.
math.sqrt(X) % Square root of X.
math.ln(X) % Natural logarithm of X.
math.log10(X) % Logarithm to the base 10 of X.
math.log2(X) % Logarithm to the base 2 of X.
math.log(B, X) % Logarithm to the base B of X.
math.exp(X) % e raised to the power... |
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... | #VBScript | VBScript |
Sub remove_lines(filepath,start,number)
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set InFile = objFSO.OpenTextFile(filepath,1,False)
line_count = 1
discard_count = 1
out_txt = ""
Do Until InFile.AtEndOfStream
line = InFile.ReadLine
If line_count <> start Then
If InFile.AtEndOfStream = False... |
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... | #Wren | Wren | import "os" for Platform
import "io" for File
var removeLines = Fn.new { |fileName, startLine, numLines|
if (fileName == "" || startLine < 1 || numLines < 1) Fiber.abort("Invalid argument(s).")
if (!File.exists(fileName)) Fiber.abort("Can't find %(fileName).")
var text = File.read(fileName)
System.pri... |
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... | #Ol | Ol |
(define content (bytes->string
(vec-iter
(file->vector "file.txt"))))
(print content)
|
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... | #ooRexx | ooRexx | file = 'c:\test.txt'
myStream = .stream~new(file)
myString = myStream~charIn(,myStream~chars) |
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
| #Toka | Toka | #! Include the regex library
needs regex
#! The two test strings
" This is a string" is-data test.1
" Another string" is-data test.2
#! Create a new regex named 'expression' which tries
#! to match strings beginning with 'This'.
" ^This" regex: expression
#! An array to store the results of the match
#! (Element... |
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
| #TXR | TXR | @(collect)
@(coll :gap 0)@mismatch@{match /dog/}@(end)@suffix
@(output)
@(rep)@{mismatch}cat@(end)@suffix
@(end)
@(end) |
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
... | #Elixir | Elixir |
IO.puts (String.reverse "asdf")
IO.puts (String.reverse "as⃝df̅")
|
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Tailspin | Tailspin |
def input: ['---------- Ice and Fire ------------',
'',
'fire, in end will world the say Some',
'ice. in say Some',
'desire of tasted I''ve what From',
'fire. favor who those with hold I',
'',
... |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Tcl | Tcl | set lines {
"---------- Ice and Fire ------------"
""
"fire, in end will world the say Some"
"ice. in say Some"
"desire of tasted I've what From"
"fire. favor who those with hold I"
""
"... elided paragraph last ..."
""
"Frost Robert -----------------------"
}
foreach line $lines... |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #X86_Assembly | X86 Assembly | format ELF executable 3
entry start
segment readable writeable
buf rb 1
segment readable executable
start: mov eax, 3 ; syscall "read"
mov ebx, 0 ; stdin
mov ecx, buf ; buffer for read byte
mov edx, 1 ; len (read one byte)
int 80h
cmp eax, 0 ; EOF?
jz exit
xor eax, eax ; load read char to eax
mo... |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #Wren | Wren | var romans = [
[1000, "M"],
[900, "CM"],
[500, "D"],
[400, "CD"],
[100, "C"],
[90, "XC"],
[50, "L"],
[40, "XL"],
[10, "X"],
[9, "IX"],
[5, "V"],
[4, "IV"],
[1, "I"]
]
var encode = Fn.new { |n|
if (n > 5000 || n < 1) return null
var res = ""... |
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... | #MATLAB_.2F_Octave | MATLAB / Octave | function S = repeat(s , n)
S = repmat(s , [1,n]) ;
return |
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... | #Maxima | Maxima | "$*"(s, n) := apply(sconcat, makelist(s, n))$
infix("$*")$
"abc" $* 5;
/* "abcabcabcabcabc" */ |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #jq | jq | [4,3,2,1,1,2,3,4] | unique |
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... | #R | R | rref <- function(m) {
pivot <- 1
norow <- nrow(m)
nocolumn <- ncol(m)
for(r in 1:norow) {
if ( nocolumn <= pivot ) break;
i <- r
while( m[i,pivot] == 0 ) {
i <- i + 1
if ( norow == i ) {
i <- r
pivot <- pivot + 1
if ( nocolumn == pivot ) return(m)
}
}
... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Metafont | Metafont | show mexp(256); % outputs e; since MF uses mexp(x) = exp(x/256)
show 3.14159; % no pi constant built in; of course we can define it
% in several ways... even computing
% C/2r (which would be funny since MF handles paths,
% and a circle is a path...)
show sqrt2... |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #min | min | e ; e
pi ; π
sqrt ; square root
log10 ; common logarithm
log2 ; binary logarithm
; no exponential
; no absolute value
floor ; greatest whole number smaller than or equal
ceil ; smallest whole number greater than or equal
trunc ; remove the fractional part (i.e. round towards 0)... |
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... | #zkl | zkl | fcn deleteLinesM(fname, start,num){
blob:=File(fname).read(); // file to memory
n:=blob.seek(Void,start-1); // seek to line and remember it
blob.del(n,blob.seek(Void,num)-n);
File.stdout.write(blob);
}
deleteLinesM("nn.zkl", 2,5); |
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... | #Oz | Oz | declare
FileHandle = {New Open.file init(name:"test.txt")}
FileContents = {FileHandle read(size:all list:$)}
in
{FileHandle close}
{System.printInfo FileContents} |
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... | #Panda | Panda | file:readme.txt .text |
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
| #UNIX_Shell | UNIX Shell | s="I am a string"
if [[ $s =~ str..g$ ]]; then
echo "the string ends with 'str..g'"
fi |
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