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/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #GUISS | GUISS | Start,Programs,Accessories,Notepad |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Go | Go | package main
import (
"fmt"
"strings"
)
func wrap(text string, lineWidth int) (wrapped string) {
words := strings.Fields(text)
if len(words) == 0 {
return
}
wrapped = words[0]
spaceLeft := lineWidth - len(wrapped)
for _, word := range words[1:] {
if len(word)+1 > spaceLeft {
wrapped += "\n" + word
spaceLeft = lineWidth - len(word)
} else {
wrapped += " " + word
spaceLeft -= 1 + len(word)
}
}
return
}
var frog = `
In olden times when wishing still helped one, there lived a king
whose daughters were all beautiful, but the youngest was so beautiful
that the sun itself, which has seen so much, was astonished whenever
it shone in her face. Close by the king's castle lay a great dark
forest, and under an old lime-tree in the forest was a well, and when
the day was very warm, the king's child went out into the forest and
sat down by the side of the cool fountain, and when she was bored she
took a golden ball, and threw it up on high and caught it, and this
ball was her favorite plaything.`
func main() {
fmt.Println("wrapped at 80:")
fmt.Println(wrap(frog, 80))
fmt.Println("wrapped at 72:")
fmt.Println(wrap(frog, 72))
} |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #Phix | Phix | with javascript_semantics
constant {hchars,hsubs} = columnize({{"<","<"},
{">",">"},
{"&","&"},
{"\"","""},
{"\'","'"}})
function xmlquote_all(sequence s)
for i=1 to length(s) do
s[i] = substitute_all(s[i],hchars,hsubs)
end for
return s
end function
function xml_CharacterRemarks(sequence data)
string res = "<CharacterRemarks>\n"
for i=1 to length(data) do
res &= sprintf(" <CharacterName=\"%s\">%s</Character>\n",xmlquote_all(data[i]))
end for
return res & "</CharacterRemarks>\n"
end function
constant testset = {
{"April", "Bubbly: I'm > Tam and <= Emily"},
{"Tam O'Shanter", "Burns: \"When chapman billies leave the street ...\""},
{"Emily", "Short & shrift"}
}
printf(1,xml_CharacterRemarks(testset))
-- Sample output:
-- <CharacterRemarks>
-- <CharacterName="April">Bubbly: I'm > Tam and <= Emily</Character>
-- <CharacterName="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
-- <CharacterName="Emily">Short & shrift</Character>
-- </CharacterRemarks>
|
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #newLISP | newLISP |
(set 'xml-input "<Students>
<Student Name=\"April\" Gender=\"F\" DateOfBirth=\"1989-01-02\" />
<Student Name=\"Bob\" Gender=\"M\" DateOfBirth=\"1990-03-04\" />
<Student Name=\"Chad\" Gender=\"M\" DateOfBirth=\"1991-05-06\" />
<Student Name=\"Dave\" Gender=\"M\" DateOfBirth=\"1992-07-08\">
<Pet Type=\"dog\" Name=\"Rover\" />
</Student>
<Student DateOfBirth=\"1993-09-10\" Gender=\"F\" Name=\"Émily\" />
</Students>")
(set 'sexp (xml-parse xml-input))
(dolist (x (ref-all "Name" sexp))
(if (= (length x) 6)
(println (last (sexp (chop x))))))
|
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #Vlang | Vlang | // Arrays, in V
// Tectonics: v run arrays.v
module main
// A little bit about V variables. V does not allow uninitialized data.
// If an identifier exists, there is a valid value. "Empty" arrays have
// values in all positions, and V provides defaults for base types if not
// explicitly specified. E.g. 0 for numbers, `0` for rune, "" for strings.
// V uses := for definition and initialization, and = for assignment
// starts here, V programs start by invoking the "main" function.
pub fn main() {
// Array definition in source literal form (immutable)
array := [1,2,3,4]
// print first element, 0 relative indexing
println("array: $array")
println("array[0]: ${array[0]}")
// immutable arrays cannot be modified after initialization
// array[1] = 5, would fail to compile with a message it needs mut
// Dynamic arrays have some property fields
println("array.len: $array.len")
println("array.cap: $array.cap")
// array specs are [n]type{properties}
// Dynamic array definition, initial default values, "" for string
mut array2 := []string{}
// Append an element, using lessless
array2 << "First"
println("array2[0]: ${array2[0]}")
println("array2.len: $array2.len")
println("array2.cap: $array2.cap")
// Fixed array definition, capacity is fixed (! suffix), mutable entries
mut array3 := ["First", "Second", "Third"]!
println("array3: $array3")
array3[array3.len-1] = "Last"
println("array3: $array3")
println("array3.len: $array3.len")
// Advanced, array intiailization using non default value
mut array4 := [4]int{init: 42}
array4[2] = 21
println("array4: $array4")
// Arrays can be sliced, creating a copy
mut array5 := array4[0..3]
println("array5: $array5")
array5[2] = 10
println("array4: $array4")
println("array5: $array5")
} |
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #Objeck | Objeck |
bundle Default {
class Doors {
function : Main(args : String[]) ~ Nil {
doors := Bool->New[100];
for(pass := 0; pass < 10; pass += 1;) {
doors[(pass + 1) * (pass + 1) - 1] := true;
};
for(i := 0; i < 100; i += 1;) {
IO.Console->GetInstance()->Print("Door #")->Print(i + 1)->Print(" is ");
if(doors[i]) {
"open."->PrintLine();
}
else {
"closed."->PrintLine();
};
};
}
}
}
|
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #JavaScript | JavaScript | (() => {
'use strict';
// main :: IO ()
const main = () =>
take(25, weirds());
// weirds :: Gen [Int]
function* weirds() {
let
x = 1,
i = 1;
while (true) {
x = until(isWeird, succ, x)
console.log(i.toString() + ' -> ' + x)
yield x;
x = 1 + x;
i = 1 + i;
}
}
// isWeird :: Int -> Bool
const isWeird = n => {
const
ds = descProperDivisors(n),
d = sum(ds) - n;
return 0 < d && !hasSum(d, ds)
};
// hasSum :: Int -> [Int] -> Bool
const hasSum = (n, xs) => {
const go = (n, xs) =>
0 < xs.length ? (() => {
const
h = xs[0],
t = xs.slice(1);
return n < h ? (
go(n, t)
) : (
n == h || hasSum(n - h, t) || hasSum(n, t)
);
})() : false;
return go(n, xs);
};
// descProperDivisors :: Int -> [Int]
const descProperDivisors = n => {
const
rRoot = Math.sqrt(n),
intRoot = Math.floor(rRoot),
blnPerfect = rRoot === intRoot,
lows = enumFromThenTo(intRoot, intRoot - 1, 1)
.filter(x => (n % x) === 0);
return (
reverse(lows)
.slice(1)
.map(x => n / x)
).concat((blnPerfect ? tail : id)(lows))
};
// GENERIC FUNCTIONS ----------------------------
// enumFromThenTo :: Int -> Int -> Int -> [Int]
const enumFromThenTo = (x1, x2, y) => {
const d = x2 - x1;
return Array.from({
length: Math.floor(y - x2) / d + 2
}, (_, i) => x1 + (d * i));
};
// id :: a -> a
const id = x => x;
// reverse :: [a] -> [a]
const reverse = xs =>
'string' !== typeof xs ? (
xs.slice(0).reverse()
) : xs.split('').reverse().join('');
// succ :: Enum a => a -> a
const succ = x => 1 + x;
// sum :: [Num] -> Num
const sum = xs => xs.reduce((a, x) => a + x, 0);
// tail :: [a] -> [a]
const tail = xs => 0 < xs.length ? xs.slice(1) : [];
// take :: Int -> [a] -> [a]
// take :: Int -> String -> String
const take = (n, xs) =>
'GeneratorFunction' !== xs.constructor.constructor.name ? (
xs.slice(0, n)
) : [].concat.apply([], Array.from({
length: n
}, () => {
const x = xs.next();
return x.done ? [] : [x.value];
}));
// until :: (a -> Bool) -> (a -> a) -> a -> a
const until = (p, f, x) => {
let v = x;
while (!p(v)) v = f(v);
return v;
};
// MAIN ---
return main();
})(); |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Pascal | Pascal |
program WritePascal;
const
i64: int64 = 1055120232691680095; (* This defines "Pascal" *)
cc: array[-1..15] of string = (* Here are all string-constants *)
('_______v---',
'__', '\_', '___', '\__',
' ', ' ', ' ', ' ',
'/ ', ' ', '_/ ', '\/ ',
' _', '__', ' _', ' _');
var
x, y: integer;
begin
for y := 0 to 7 do
begin
Write(StringOfChar(cc[(not y and 1) shl 2][1], 23 - y and 6));
Write(cc[((i64 shr (y div 2)) and 1) shl 3 + (not y and 1) shl 2 + 2]);
for x := 0 to 15 do
Write(cc[((i64 shr ((x and 15) * 4 + y div 2)) and 1) +
((i64 shr (((x + 1) and 15) * 4 + y div 2)) and 1) shl 3 +
(x mod 3) and 2 + (not y and 1) shl 2]);
writeln(cc[1 + (not y and 1) shl 2] + cc[(not y and 1) shl 3 - 1]);
end;
end.
|
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #Clojure | Clojure |
(second (re-find #" (\d{1,2}:\d{1,2}:\d{1,2}) UTC" (slurp "http://tycho.usno.navy.mil/cgi-bin/timer.pl")))
|
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #CoffeeScript | CoffeeScript |
http = require 'http'
CONFIG =
host: 'tycho.usno.navy.mil'
path: '/cgi-bin/timer.pl'
# Web scraping code tends to be brittle, and this is no exception.
# The tycho time page does not use highly structured markup, so
# we do a real dirty scrape.
scrape_tycho_ust_time = (text) ->
for line in text.split '\n'
matches = line.match /(.*:\d\d UTC)/
if matches
console.log matches[0].replace '<BR>', ''
return
throw Error("unscrapable page!")
# This is low-level-ish code to get data from a URL. It's
# pretty general purpose, so you'd normally tuck this away
# in a library (or use somebody else's library).
wget = (host, path, cb) ->
options =
host: host
path: path
headers:
"Cache-Control": "max-age=0"
req = http.request options, (res) ->
s = ''
res.on 'data', (chunk) ->
s += chunk
res.on 'end', ->
cb s
req.end()
# Do our web scrape
do ->
wget CONFIG.host, CONFIG.path, (data) ->
scrape_tycho_ust_time data
|
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Clojure | Clojure | (defn count-words [file n]
(->> file
slurp
clojure.string/lower-case
(re-seq #"\w+")
frequencies
(sort-by val >)
(take n))) |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #COBOL | COBOL |
IDENTIFICATION DIVISION.
PROGRAM-ID. WordFrequency.
AUTHOR. Bill Gunshannon.
DATE-WRITTEN. 30 Jan 2020.
************************************************************
** Program Abstract:
** Given a text file and an integer n, print the n most
** common words in the file (and the number of their
** occurrences) in decreasing frequency.
**
** A file named Parameter.txt provides this information.
** Format is:
** 12345678901234567890123456789012345678901234567890
** |------------------|----|
** ^^^^^^^^^^^^^^^^ ^^^^
** | |
** Source Text File Number of words with count
** 20 Characters 5 digits with leading zeroes
**
**
************************************************************
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT Parameter-File ASSIGN TO "Parameter.txt"
ORGANIZATION IS LINE SEQUENTIAL.
SELECT Input-File ASSIGN TO Source-Text
ORGANIZATION IS LINE SEQUENTIAL.
SELECT Word-File ASSIGN TO "Word.txt"
ORGANIZATION IS LINE SEQUENTIAL.
SELECT Output-File ASSIGN TO "Output.txt"
ORGANIZATION IS LINE SEQUENTIAL.
SELECT Print-File ASSIGN TO "Printer.txt"
ORGANIZATION IS LINE SEQUENTIAL.
SELECT Sort-File ASSIGN TO DISK.
DATA DIVISION.
FILE SECTION.
FD Parameter-File
DATA RECORD IS Parameter-Record.
01 Parameter-Record.
05 Source-Text PIC X(20).
05 How-Many PIC 99999.
FD Input-File
DATA RECORD IS Input-Record.
01 Input-Record.
05 Input-Line PIC X(80).
FD Word-File
DATA RECORD IS Word-Record.
01 Word-Record.
05 Input-Word PIC X(20).
FD Output-File
DATA RECORD IS Output-Rec.
01 Output-Rec.
05 Output-Rec-Word PIC X(20).
05 Output-Rec-Word-Cnt PIC 9(5).
FD Print-File
DATA RECORD IS Print-Rec.
01 Print-Rec.
05 Print-Rec-Word PIC X(20).
05 Print-Rec-Word-Cnt PIC 9(5).
SD Sort-File.
01 Sort-Rec.
05 Sort-Word PIC X(20).
05 Sort-Word-Cnt PIC 9(5).
WORKING-STORAGE SECTION.
01 Eof PIC X VALUE 'F'.
01 InLine PIC X(80).
01 Word1 PIC X(20).
01 Current-Word PIC X(20).
01 Current-Word-Cnt PIC 9(5).
01 Pos PIC 99
VALUE 1.
01 Cnt PIC 99.
01 Report-Rank.
05 IRank PIC 99999
VALUE 1.
05 Rank PIC ZZZZ9.
PROCEDURE DIVISION.
Main-Program.
**
** Read the Parameters
**
OPEN INPUT Parameter-File.
READ Parameter-File.
CLOSE Parameter-File.
**
** Open Files for first stage
**
OPEN INPUT Input-File.
OPEN OUTPUT Word-File.
**
** Pare\se the Source Text into a file of invidual words
**
PERFORM UNTIL Eof = 'T'
READ Input-File
AT END MOVE 'T' TO Eof
END-READ
PERFORM Parse-a-Words
MOVE SPACES TO Input-Record
MOVE 1 TO Pos
END-PERFORM.
**
** Cleanup from the first stage
**
CLOSE Input-File Word-File
**
** Sort the individual words in alphabetical order
**
SORT Sort-File
ON ASCENDING KEY Sort-Word
USING Word-File
GIVING Word-File.
**
** Count each time a word is used
**
PERFORM Collect-Totals.
**
** Sort data by number of usages per word
**
SORT Sort-File
ON DESCENDING KEY Sort-Word-Cnt
USING Output-File
GIVING Print-File.
**
** Show the work done
**
OPEN INPUT Print-File.
DISPLAY " Rank Word Frequency"
PERFORM How-Many TIMES
READ Print-File
MOVE IRank TO Rank
DISPLAY Rank " " Print-Rec
ADD 1 TO IRank
END-PERFORM.
**
** Cleanup
**
CLOSE Print-File.
CALL "C$DELETE" USING "Word.txt" ,0
CALL "C$DELETE" USING "Output.txt" ,0
STOP RUN.
Parse-a-Words.
INSPECT Input-Record CONVERTING '-.,"();:/[]{}!?|' TO SPACE
PERFORM UNTIL Pos > FUNCTION STORED-CHAR-LENGTH(Input-Record)
UNSTRING Input-Record DELIMITED BY SPACE INTO Word1
WITH POINTER Pos TALLYING IN Cnt
MOVE FUNCTION TRIM(FUNCTION LOWER-CASE(Word1)) TO Word-Record
IF Word-Record NOT EQUAL SPACES AND Word-Record IS ALPHABETIC
THEN WRITE Word-Record
END-IF
END-PERFORM.
Collect-Totals.
MOVE 'F' to Eof
OPEN INPUT Word-File
OPEN OUTPUT Output-File
READ Word-File
MOVE Input-Word TO Current-Word
MOVE 1 to Current-Word-Cnt
PERFORM UNTIL Eof = 'T'
READ Word-File
AT END MOVE 'T' TO Eof
END-READ
IF FUNCTION TRIM(Word-Record)
EQUAL
FUNCTION TRIM(Current-Word)
THEN
ADD 1 to Current-Word-Cnt
ELSE
MOVE Current-Word TO Output-Rec-Word
MOVE Current-Word-Cnt TO Output-Rec-Word-Cnt
WRITE Output-Rec
MOVE 1 to Current-Word-Cnt
MOVE Word-Record TO Current-Word
MOVE SPACES TO Input-Record
END-IF
END-PERFORM.
CLOSE Word-File Output-File.
END-PROGRAM.
|
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneously.
The cell transition rules are this:
Input State
Output State
Condition
empty
empty
electron head
electron tail
electron tail
conductor
conductor
electron head
if 1 or 2 cells in the neighborhood of the cell are in the state “electron head”
conductor
conductor
otherwise
Task
Create a program that reads a Wireworld program from a file and displays an animation of the processing. Here is a sample description file (using "H" for an electron head, "t" for a tail, "." for a conductor and a space for empty) you may wish to test with, which demonstrates two cycle-3 generators and an inhibit gate:
tH.........
. .
...
. .
Ht.. ......
While text-only implementations of this task are possible, mapping cells to pixels is advisable if you wish to be able to display large designs. The logic is not significantly more complex.
| #FreeBASIC | FreeBASIC | #define MAXX 319
#define MAXY 199
enum state
E=0, C=8, H=9, T=4 'doubles as colours: black, grey, bright blue, red
end enum
dim as uinteger world(0 to 1, 0 to MAXX, 0 to MAXY), active = 0, buffer = 1
dim as double rate = 1./3. 'seconds per frame
dim as double tick
dim as uinteger x, y
function turn_on( world() as unsigned integer, x as uinteger, y as uinteger, a as uinteger ) as boolean
dim as ubyte n = 0
dim as integer qx, qy
for qx = -1 to 1
for qy = -1 to 1
if qx=0 andalso qy=0 then continue for
if world(a,(x+qx+MAXX+1) mod (MAXX+1), (y+qy+MAXY+1) mod (MAXY+1))=H then n=n+1 'handles wrap-around
next qy
next qx
if n=1 then return true
if n=2 then return true
return false
end function
'generate sample map
for x=20 to 30
world(active, x, 20) = C
world(active, x, 24) = C
next x
world(active, 24, 24 ) = E
world(active, 20, 21 ) = C
world(active, 20, 23 ) = C
world(active, 24, 21 ) = C
world(active, 23, 22 ) = C
world(active, 24, 22 ) = C
world(active, 25, 22 ) = C
world(active, 24, 23 ) = C
world(active, 20, 20 ) = T
world(active, 21, 20 ) = H
world(active, 21, 24 ) = T
world(active, 20, 24 ) = H
screen 12
do
tick = timer
for x = 0 to 319
for y = 0 to 199
pset (x,y), world(active, x, y)
if world(active,x,y) = E then world(buffer,x,y) = E 'empty cells stay empty
if world(active,x,y) = H then world(buffer,x,y) = T 'electron heads turn into electron tails
if world(active,x,y) = T then world(buffer,x,y) = C 'electron tails revert to conductors
if world(active,x,y) = C then
if turn_on(world(),x,y,active) then
world(buffer,x,y) = H 'maybe electron heads spread
else
world(buffer,x,y) = C 'otherwise condutor remains conductor
end if
end if
next y
next x
while tick + rate > timer
wend
cls
buffer = 1 - buffer
active = 1 - buffer
loop |
http://rosettacode.org/wiki/Window_creation/X11 | Window creation/X11 | Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| #TXR | TXR | /* window_creation_x11.wren */
var KeyPressMask = 1 << 0
var ExposureMask = 1 << 15
var KeyPress = 2
var Expose = 12
foreign class XGC {
construct default(display, screenNumber) {}
}
foreign class XEvent {
construct new() {}
foreign eventType
}
foreign class XDisplay {
construct openDisplay(displayName) {}
foreign defaultScreen()
foreign rootWindow(screenNumber)
foreign blackPixel(screenNumber)
foreign whitePixel(screenNumber)
foreign selectInput(w, eventMask)
foreign mapWindow(w)
foreign closeDisplay()
foreign nextEvent(eventReturn)
foreign createSimpleWindow(parent, x, y, width, height, borderWidth, border, background)
foreign fillRectangle(d, gc, x, y, width, height)
foreign drawString(d, gc, x, y, string, length)
}
var xd = XDisplay.openDisplay("")
if (xd == 0) {
System.print("Cannot open display.")
return
}
var s = xd.defaultScreen()
var w = xd.createSimpleWindow(xd.rootWindow(s), 10, 10, 100, 100, 1, xd.blackPixel(s), xd.whitePixel(s))
xd.selectInput(w, ExposureMask | KeyPressMask)
xd.mapWindow(w)
var msg = "Hello, World!"
var e = XEvent.new()
while (true) {
xd.nextEvent(e)
var gc = XGC.default(xd, s)
if (e.eventType == Expose) {
xd.fillRectangle(w, gc, 20, 20, 10, 10)
xd.drawString(w, gc, 10, 50, msg, msg.count)
}
if (e.eventType == KeyPress) break
}
xd.closeDisplay() |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Haskell | Haskell | import Graphics.HGL
aWindow = runGraphics $
withWindow_ "Rosetta Code task: Creating a window" (300, 200) $ \ w -> do
drawInWindow w $ text (100, 100) "Hello World"
getKey w |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #HicEst | HicEst | WINDOW(WINdowhandle=handle, Width=80, Height=-400, X=1, Y=1/2, TItle="Rosetta Window_creation Example")
! window units: as pixels < 0, as relative window size 0...1, ascurrent character sizes > 1
WRITE(WINdowhandle=handle) '... some output ...' |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Groovy | Groovy | def wordWrap(text, length = 80) {
def sb = new StringBuilder()
def line = ''
text.split(/\s/).each { word ->
if (line.size() + word.size() > length) {
sb.append(line.trim()).append('\n')
line = ''
}
line += " $word"
}
sb.append(line.trim()).toString()
} |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #PicoLisp | PicoLisp | (load "@lib/xml.l")
(de characterRemarks (Names Remarks)
(xml
(cons
'CharacterRemarks
NIL
(mapcar
'((Name Remark)
(list 'Character (list (cons 'name Name)) Remark) )
Names
Remarks ) ) ) )
(characterRemarks
'("April" "Tam O'Shanter" "Emily")
(quote
"I'm > Tam and <= Emily"
"Burns: \"When chapman billies leave the street ..."
"Short & shrift" ) ) |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #PureBasic | PureBasic | DataSection
dataItemCount:
Data.i 3
names:
Data.s "April", "Tam O'Shanter", "Emily"
remarks:
Data.s "Bubbly: I'm > Tam and <= Emily",
~"Burns: \"When chapman billies leave the street ...\"",
"Short & shrift"
EndDataSection
Structure characteristic
name.s
remark.s
EndStructure
NewList didel.characteristic()
Define item.s, numberOfItems, i
Restore dataItemCount
Read.i numberOfItems
;add names
Restore names
For i = 1 To numberOfItems
AddElement(didel())
Read.s item
didel()\name = item
Next
;add remarks
ResetList(didel())
FirstElement(didel())
Restore remarks:
For i = 1 To numberOfItems
Read.s item
didel()\remark = item
NextElement(didel())
Next
Define xml, mainNode, itemNode
ResetList(didel())
FirstElement(didel())
xml = CreateXML(#PB_Any)
mainNode = CreateXMLNode(RootXMLNode(xml), "CharacterRemarks")
ForEach didel()
itemNode = CreateXMLNode(mainNode, "Character")
SetXMLAttribute(itemNode, "name", didel()\name)
SetXMLNodeText(itemNode, didel()\remark)
Next
FormatXML(xml, #PB_XML_ReFormat | #PB_XML_WindowsNewline | #PB_XML_ReIndent)
If OpenConsole()
PrintN(ComposeXML(xml, #PB_XML_NoDeclaration))
Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input()
CloseConsole()
EndIf |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #Nim | Nim | import xmlparser, xmltree, streams
let doc = newStringStream """<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>"""
for i in doc.parseXml.findAll "Student":
echo i.attr "Name" |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #Objeck | Objeck |
use XML;
bundle Default {
class Test {
function : Main(args : String[]) ~ Nil {
in := String->New();
in->Append("<Students>");
in->Append("<Student Name=\"April\" Gender=\"F\" DateOfBirth=\"1989-01-02\" />");
in->Append("<Student Name=\"Bob\" Gender=\"M\" DateOfBirth=\"1990-03-04\" />");
in->Append("<Student Name=\"Chad\" Gender=\"M\" DateOfBirth=\"1991-05-06\" />");
in->Append("<Student Name=\"Dave\" Gender=\"M\" DateOfBirth=\"1992-07-08\">");
in->Append("<Pet Type=\"dog\" Name=\"Rover\" />");
in->Append("</Student>");
in->Append("<Student DateOfBirth=\"1993-09-10\" Gender=\"F\" Name=\"Émily\" /></Students>");
parser := XmlParser->New(in);
if(parser->Parse()) {
root := parser->GetRoot();
children := root->GetChildren("Student");
each(i : children) {
child : XMLElement := children->Get(i)->As(XMLElement);
XMLElement->DecodeString(child->GetAttribute("Name"))->PrintLine();
};
};
}
}
}
|
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #Wee_Basic | Wee Basic | dim array$(2)
let array$(1)="Hello!"
let array$(2)="Goodbye!"
print 1 array$(1) |
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #Objective-C | Objective-C |
@import Foundation;
int main(int argc, const char * argv[]) {
@autoreleasepool {
// Create a mutable array
NSMutableArray *doorArray = [@[] mutableCopy];
// Fill the doorArray with 100 closed doors
for (NSInteger i = 0; i < 100; ++i) {
doorArray[i] = @NO;
}
// Do the 100 passes
for (NSInteger pass = 0; pass < 100; ++pass) {
for (NSInteger door = pass; door < 100; door += pass+1) {
doorArray[door] = [doorArray[door] isEqual: @YES] ? @NO : @YES;
}
}
// Print the results
[doorArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
if ([obj isEqual: @YES]) {
NSLog(@"Door number %lu is open", idx + 1);
}
}];
}
}
|
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Julia | Julia | using Primes
function nosuchsum(revsorted, num)
if sum(revsorted) < num
return true
end
for (i, n) in enumerate(revsorted)
if n > num
continue
elseif n == num
return false
elseif !nosuchsum(revsorted[i+1:end], num - n)
return false
end
end
true
end
function isweird(n)
if n < 70 || isodd(n)
return false
else
f = [one(n)]
for (p, x) in factor(n)
f = reduce(vcat, [f*p^i for i in 1:x], init=f)
end
pop!(f)
return sum(f) > n && nosuchsum(sort(f, rev=true), n)
end
end
function testweird(N)
println("The first $N weird numbers are: ")
count, n = 0, 69
while count < N
if isweird(n)
count += 1
print("$n ")
end
n += 1
end
end
testweird(25)
|
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Kotlin | Kotlin | // Version 1.3.21
fun divisors(n: Int): List<Int> {
val divs = mutableListOf(1)
val divs2 = mutableListOf<Int>()
var i = 2
while (i * i <= n) {
if (n % i == 0) {
val j = n / i
divs.add(i)
if (i != j) divs2.add(j)
}
i++
}
divs2.addAll(divs.asReversed())
return divs2
}
fun abundant(n: Int, divs: List<Int>) = divs.sum() > n
fun semiperfect(n: Int, divs: List<Int>): Boolean {
if (divs.size > 0) {
val h = divs[0]
val t = divs.subList(1, divs.size)
if (n < h) {
return semiperfect(n, t)
} else {
return n == h || semiperfect(n-h, t) || semiperfect(n, t)
}
} else {
return false
}
}
fun sieve(limit: Int): BooleanArray {
// false denotes abundant and not semi-perfect.
// Only interested in even numbers >= 2
val w = BooleanArray(limit)
for (i in 2 until limit step 2) {
if (w[i]) continue
val divs = divisors(i)
if (!abundant(i, divs)) {
w[i] = true
} else if (semiperfect(i, divs)) {
for (j in i until limit step i) w[j] = true
}
}
return w
}
fun main() {
val w = sieve(17000)
var count = 0
val max = 25
println("The first 25 weird numbers are:")
var n = 2
while (count < max) {
if (!w[n]) {
print("$n ")
count++
}
n += 2
}
println()
} |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Perl | Perl | #!/usr/bin/perl
use strict;
use warnings;
for my $tuple ([" ", 2], ["_", 1], [" ", 1], ["\\", 1], [" ", 11], ["|", 1], ["\n", 1],
[" ", 1], ["|", 1], [" ", 3], ["|", 1], [" ", 1], ["_", 1], [" ", 1], ["\\", 1], [" ", 2], ["_", 2], ["|", 1], [" ", 1], ["|", 1], ["\n", 1],
[" ", 1], ["_", 3], ["/", 1], [" ", 2], ["_", 2], ["/", 1], [" ", 1], ["|", 1], [" ", 4], ["|", 1], ["\n", 1],
["_", 1], ["|", 1], [" ", 3], ["\\", 1], ["_", 3], ["|", 1], ["_", 1], ["|", 1], [" ", 3], ["_", 1], ["|", 1], ["\n", 1]
) {
print $tuple->[0] x $tuple->[1];
} |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #Common_Lisp | Common Lisp | BOA> (let* ((url "http://tycho.usno.navy.mil/cgi-bin/timer.pl")
(regexp (load-time-value
(cl-ppcre:create-scanner "(?m)^.{4}(.+? UTC)")))
(data (drakma:http-request url)))
(multiple-value-bind (start end start-regs end-regs)
(cl-ppcre:scan regexp data)
(declare (ignore end))
(when start
(subseq data (aref start-regs 0) (aref end-regs 0)))))
"Aug. 12, 04:29:51 UTC" |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Common_Lisp | Common Lisp |
(defun count-word (n pathname)
(with-open-file (s pathname :direction :input)
(loop for line = (read-line s nil nil) while line
nconc (list-symb (drop-noise line)) into words
finally (return (subseq (sort (pair words)
#'> :key #'cdr)
0 n)))))
(defun list-symb (s)
(let ((*read-eval* nil))
(read-from-string (concatenate 'string "(" s ")"))))
(defun drop-noise (s)
(delete-if-not #'(lambda (x) (or (alpha-char-p x)
(equal x #\space)
(equal x #\-))) s))
(defun pair (words &aux (hash (make-hash-table)) ac)
(dolist (word words) (incf (gethash word hash 0)))
(maphash #'(lambda (e n) (push `(,e . ,n) ac)) hash) ac)
|
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneously.
The cell transition rules are this:
Input State
Output State
Condition
empty
empty
electron head
electron tail
electron tail
conductor
conductor
electron head
if 1 or 2 cells in the neighborhood of the cell are in the state “electron head”
conductor
conductor
otherwise
Task
Create a program that reads a Wireworld program from a file and displays an animation of the processing. Here is a sample description file (using "H" for an electron head, "t" for a tail, "." for a conductor and a space for empty) you may wish to test with, which demonstrates two cycle-3 generators and an inhibit gate:
tH.........
. .
...
. .
Ht.. ......
While text-only implementations of this task are possible, mapping cells to pixels is advisable if you wish to be able to display large designs. The logic is not significantly more complex.
| #GML | GML | //Create event
/*
Wireworld first declares constants and then reads a wireworld from a textfile.
In order to implement wireworld in GML a single array is used.
To make it behave properly, there need to be states that are 'in-between' two states:
0 = empty
1 = conductor from previous state
2 = electronhead from previous state
5 = electronhead that was a conductor in the previous state
3 = electrontail from previous state
4 = electrontail that was a head in the previous state
*/
empty = 0;
conduc = 1;
eHead = 2;
eTail = 3;
eHead_to_eTail = 4;
coduc_to_eHead = 5;
working = true;//not currently used, but setting it to false stops wireworld. (can be used to pause)
toroidalMode = false;
factor = 3;//this is used for the display. 3 means a single pixel is multiplied by three in size.
var tempx,tempy ,fileid, tempstring, gridid, listid, maxwidth, stringlength;
tempx = 0;
tempy = 0;
tempstring = "";
maxwidth = 0;
//the next piece of code loads the textfile containing a wireworld.
//the program will not work correctly if there is no textfile.
if file_exists("WW.txt")
{
fileid = file_text_open_read("WW.txt");
gridid = ds_grid_create(0,0);
listid = ds_list_create();
while !file_text_eof(fileid)
{
tempstring = file_text_read_string(fileid);
stringlength = string_length(tempstring);
ds_list_add(listid,stringlength);
if maxwidth < stringlength
{
ds_grid_resize(gridid,stringlength,ds_grid_height(gridid) + 1)
maxwidth = stringlength
}
else
{
ds_grid_resize(gridid,maxwidth,ds_grid_height(gridid) + 1)
}
for (i = 1; i <= stringlength; i +=1)
{
switch (string_char_at(tempstring,i))
{
case ' ': ds_grid_set(gridid,tempx,tempy,empty); break;
case '.': ds_grid_set(gridid,tempx,tempy,conduc); break;
case 'H': ds_grid_set(gridid,tempx,tempy,eHead); break;
case 't': ds_grid_set(gridid,tempx,tempy,eTail); break;
default: break;
}
tempx += 1;
}
file_text_readln(fileid);
tempy += 1;
tempx = 0;
}
file_text_close(fileid);
//fill the 'open' parts of the grid
tempy = 0;
repeat(ds_list_size(listid))
{
tempx = ds_list_find_value(listid,tempy);
repeat(maxwidth - tempx)
{
ds_grid_set(gridid,tempx,tempy,empty);
tempx += 1;
}
tempy += 1;
}
boardwidth = ds_grid_width(gridid);
boardheight = ds_grid_height(gridid);
//the contents of the grid are put in a array, because arrays are faster.
//the grid was needed because arrays cannot be resized properly.
tempx = 0;
tempy = 0;
repeat(boardheight)
{
repeat(boardwidth)
{
board[tempx,tempy] = ds_grid_get(gridid,tempx,tempy);
tempx += 1;
}
tempy += 1;
tempx = 0;
}
//the following code clears memory
ds_grid_destroy(gridid);
ds_list_destroy(listid);
} |
http://rosettacode.org/wiki/Window_creation/X11 | Window creation/X11 | Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| #Wren | Wren | /* window_creation_x11.wren */
var KeyPressMask = 1 << 0
var ExposureMask = 1 << 15
var KeyPress = 2
var Expose = 12
foreign class XGC {
construct default(display, screenNumber) {}
}
foreign class XEvent {
construct new() {}
foreign eventType
}
foreign class XDisplay {
construct openDisplay(displayName) {}
foreign defaultScreen()
foreign rootWindow(screenNumber)
foreign blackPixel(screenNumber)
foreign whitePixel(screenNumber)
foreign selectInput(w, eventMask)
foreign mapWindow(w)
foreign closeDisplay()
foreign nextEvent(eventReturn)
foreign createSimpleWindow(parent, x, y, width, height, borderWidth, border, background)
foreign fillRectangle(d, gc, x, y, width, height)
foreign drawString(d, gc, x, y, string, length)
}
var xd = XDisplay.openDisplay("")
if (xd == 0) {
System.print("Cannot open display.")
return
}
var s = xd.defaultScreen()
var w = xd.createSimpleWindow(xd.rootWindow(s), 10, 10, 100, 100, 1, xd.blackPixel(s), xd.whitePixel(s))
xd.selectInput(w, ExposureMask | KeyPressMask)
xd.mapWindow(w)
var msg = "Hello, World!"
var e = XEvent.new()
while (true) {
xd.nextEvent(e)
var gc = XGC.default(xd, s)
if (e.eventType == Expose) {
xd.fillRectangle(w, gc, 20, 20, 10, 10)
xd.drawString(w, gc, 10, 50, msg, msg.count)
}
if (e.eventType == KeyPress) break
}
xd.closeDisplay() |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #IDL | IDL | Id = WIDGET_BASE(TITLE='Window Title',xsize=200,ysize=100)
WIDGET_CONTROL, /REALIZE, id
|
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Icon_and_Unicon | Icon and Unicon | link graphics
procedure main(arglist)
WOpen("size=300, 300", "fg=blue", "bg=light gray")
WDone()
end |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #J | J | wdinfo 'Hamlet';'To be, or not to be: that is the question:' |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Haskell | Haskell | ss =
concat
[ "In olden times when wishing still helped one, there lived a king"
, "whose daughters were all beautiful, but the youngest was so beautiful"
, "that the sun itself, which has seen so much, was astonished whenever"
, "it shone in her face. Close by the king's castle lay a great dark"
, "forest, and under an old lime-tree in the forest was a well, and when"
, "the day was very warm, the king's child went out into the forest and"
, "sat down by the side of the cool fountain, and when she was bored she"
, "took a golden ball, and threw it up on high and caught it, and this"
, "ball was her favorite plaything."
]
wordwrap maxlen = wrap_ 0 . words
where
wrap_ _ [] = "\n"
wrap_ pos (w:ws)
-- at line start: put down the word no matter what
| pos == 0 = w ++ wrap_ (pos + lw) ws
| pos + lw + 1 > maxlen = '\n' : wrap_ 0 (w : ws)
| otherwise = ' ' : w ++ wrap_ (pos + lw + 1) ws
where
lw = length w
main = mapM_ putStr [wordwrap 72 ss, "\n", wordwrap 32 ss] |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #Python | Python | >>> from xml.etree import ElementTree as ET
>>> from itertools import izip
>>> def characterstoxml(names, remarks):
root = ET.Element("CharacterRemarks")
for name, remark in izip(names, remarks):
c = ET.SubElement(root, "Character", {'name': name})
c.text = remark
return ET.tostring(root)
>>> print characterstoxml(
names = ["April", "Tam O'Shanter", "Emily"],
remarks = [ "Bubbly: I'm > Tam and <= Emily",
'Burns: "When chapman billies leave the street ..."',
'Short & shrift' ] ).replace('><','>\n<') |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #OCaml | OCaml | # #directory "+xml-light" (* or maybe "+site-lib/xml-light" *) ;;
# #load "xml-light.cma" ;;
# let x = Xml.parse_string "
<Students>
<Student Name='April' Gender='F' DateOfBirth='1989-01-02' />
<Student Name='Bob' Gender='M' DateOfBirth='1990-03-04' />
<Student Name='Chad' Gender='M' DateOfBirth='1991-05-06' />
<Student Name='Dave' Gender='M' DateOfBirth='1992-07-08'>
<Pet Type='dog' Name='Rover' />
</Student>
<Student DateOfBirth='1993-09-10' Gender='F' Name='Émily' />
</Students>"
in
Xml.iter (function
Xml.Element ("Student", attrs, _) ->
List.iter (function ("Name", name) -> print_endline name | _ -> ()) attrs
| _ -> ()) x
;;
April
Bob
Chad
Dave
Émily
- : unit = () |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #Wren | Wren | var arr = []
arr.add(1)
arr.add(2)
arr.count // 2
arr.clear()
arr.add(0)
arr.add(arr[0])
arr.add(1)
arr.add(arr[-1]) // [0, 0, 1, 1]
arr[-1] = 0
arr.insert(-1, 0) // [0, 0, 1, 0, 0]
arr.removeAt(2) // [0, 0, 0, 0] |
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #OCaml | OCaml | let max_doors = 100
let show_doors =
Array.iteri (fun i x -> Printf.printf "Door %d is %s\n" (i+1)
(if x then "open" else "closed"))
let flip_doors doors =
for i = 1 to max_doors do
let rec flip idx =
if idx < max_doors then begin
doors.(idx) <- not doors.(idx);
flip (idx + i)
end
in flip (i - 1)
done;
doors
let () =
show_doors (flip_doors (Array.make max_doors false)) |
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Lua | Lua | function make(n, d)
local a = {}
for i=1,n do
table.insert(a, d)
end
return a
end
function reverse(t)
local n = #t
local i = 1
while i < n do
t[i],t[n] = t[n],t[i]
i = i + 1
n = n - 1
end
end
function tail(list)
return { select(2, unpack(list)) }
end
function divisors(n)
local divs = {}
table.insert(divs, 1)
local divs2 = {}
local i = 2
while i * i <= n do
if n % i == 0 then
local j = n / i
table.insert(divs, i)
if i ~= j then
table.insert(divs2, j)
end
end
i = i + 1
end
reverse(divs)
for i,v in pairs(divs) do
table.insert(divs2, v)
end
return divs2
end
function abundant(n, divs)
local sum = 0
for i,v in pairs(divs) do
sum = sum + v
end
return sum > n
end
function semiPerfect(n, divs)
if #divs > 0 then
local h = divs[1]
local t = tail(divs)
if n < h then
return semiPerfect(n, t)
else
return n == h
or semiPerfect(n - h, t)
or semiPerfect(n, t)
end
else
return false
end
end
function sieve(limit)
-- false denotes abundant and not semi-perfect.
-- Only interested in even numbers >= 2
local w = make(limit, false)
local i = 2
while i < limit do
if not w[i] then
local divs = divisors(i)
if not abundant(i, divs) then
w[i] = true
elseif semiPerfect(i, divs) then
local j = i
while j < limit do
w[j] = true
j = j + i
end
end
end
i = i + 1
end
return w
end
function main()
local w = sieve(17000)
local count = 0
local max = 25
print("The first 25 weird numbers:")
local n = 2
while count < max do
if not w[n] then
io.write(n, ' ')
count = count + 1
end
n = n + 2
end
print()
end
main() |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Phix | Phix | constant s = """
------*** *
-----* * *
----* * * *
---*** *
--* *** * * *
-* * * * *
* * * * * *
"""
puts(1,substitute_all(s,"* ",{"_/"," "}))
|
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #D | D | void main() {
import std.stdio, std.string, std.net.curl, std.algorithm;
foreach (line; "http://tycho.usno.navy.mil/cgi-bin/timer.pl".byLine)
if (line.canFind(" UTC"))
line[4 .. $].writeln;
} |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #Delphi | Delphi |
program WebScrape;
{$APPTYPE CONSOLE}
{.$DEFINE DEBUG}
uses
Classes,
Winsock;
{ Function to connect to host, send HTTP request and retrieve response }
function DoHTTPGET(const hostName: PAnsiChar; const resource: PAnsiChar; HTTPResponse: TStrings): Boolean;
const
Port: integer = 80;
CRLF = #13#10; // carriage return/line feed
var
WSAData: TWSAData;
Sock: TSocket;
SockAddrIn: TSockAddrIn;
IPAddress: PHostEnt;
bytesIn: integer;
inBuffer: array [0..1023] of char;
Req: string;
begin
Result := False;
HTTPResponse.Clear;
{ Initialise use of the Windows Sockets DLL.
Older Windows versions support Winsock 1.1 whilst newer Windows
include Winsock 2 but support 1.1. Therefore, we'll specify
version 1.1 ($101) as being the highest version of Windows Sockets
that we can use to provide greatest flexibility.
WSAData receives details of the Windows Sockets implementation }
Winsock.WSAStartUp($101, WSAData);
try
{ Create a socket for TCP/IP usage passing in
Address family spec: AF_INET (TCP, UDP, etc.)
Type specification: SOCK_STREAM
Protocol: IPPROTO_TCP (TCP) }
Sock := WinSock.Socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
try
// Check we have a valid socket
if (Sock <> INVALID_SOCKET) then
begin
// Populate socket address structure
with SockAddrIn do
begin
// Address family specification
sin_family := AF_INET;
// Port
sin_port := htons(Port);
// Address
sin_addr.s_addr := inet_addr(hostName);
end;
if (SockAddrIn.sin_addr.s_addr = INADDR_NONE) then
begin
{ As we're using a domain name instead of an
IP Address, we need to resolve the domain name }
IPAddress := Winsock.gethostbyname(hostName);
// Quit if we didn't get an IP Address
if (IPAddress = nil) then
Exit;
// Update the structure with the IP Address
SockAddrIn.sin_addr.s_addr := PLongint(IPAddress^.h_addr_list^)^;
end;
// Try to connect to host
if (Winsock.connect(Sock, SockAddrIn, SizeOf(SockAddrIn)) <> SOCKET_ERROR) then
begin
// OK - Connected
// Compose our request
// Each line of the request must be terminated with a carriage return/line feed
{ The First line specifies method (e.g. GET, POST), path to required resource,
and the HTTP version being used. These three fields are space separated. }
Req := 'GET '+resource+' HTTP/1.1' + CRLF +
// Host: is the only Required header in HTTP 1.1
'Host: '+hostName + CRLF +
{ Persistent connections are the default in HTTP 1.1 but, as we don't want
or need one for this exercise, we must include the "Connection: close"
header in our request }
'Connection: close' + CRLF +
CRLF; // Request must end with an empty line!
// Try to send the request to the host
if (Winsock.send(Sock,Req[1],Length(Req),0) <> SOCKET_ERROR) then
begin
// Initialise incoming data buffer (i.e. fill array with nulls)
FillChar(inBuffer,SizeOf(inBuffer),#0);
// Loop until nothing left to read
repeat
// Read incoming data from socket
bytesIn := Winsock.recv(Sock, inBuffer, SizeOf(inBuffer), 0);
// Assign buffer to Stringlist
HTTPResponse.Text := HTTPResponse.Text + Copy(string(inBuffer),1,bytesIn);
until
(bytesIn <= 0) or (bytesIn = SOCKET_ERROR);
{ Our list of response strings should
contain at least 1 line }
Result := HTTPResponse.Count > 0;
end;
end;
end;
finally
// Close our socket
Winsock.closesocket(Sock);
end;
finally
{ This causes our application to deregister itself from this
Windows Sockets implementation and allows the implementation
to free any resources allocated on our behalf. }
Winsock.WSACleanup;
end;
end;
{ Simple function to locate and return the UTC time from the
request sent to http://tycho.usno.navy.mil/cgi-bin/timer.pl
The HTTPResponse parameter contains both the HTTP Headers and
the HTML served up by the requested resource. }
function ParseResponse(HTTPResponse: TStrings): string;
var
i: Integer;
begin
Result := '';
{ Check first line for server response code
We want something like this: HTTP/1.1 200 OK }
if Pos('200',HTTPResponse[0]) > 0 then
begin
for i := 0 to Pred(HTTPResponse.Count) do
begin
{ The line we're looking for is something like this:
<BR>May. 04. 21:55:19 UTC Universal Time }
// Check each line
if Pos('UTC',HTTPResponse[i]) > 0 then
begin
Result := Copy(HTTPResponse[i],5,Pos('UTC',HTTPResponse[i])-1);
Break;
end;
end;
end
else
Result := 'HTTP Error: '+HTTPResponse[0];
end;
const
host: PAnsiChar = 'tycho.usno.navy.mil';
res : PAnsiChar = '/cgi-bin/timer.pl';
var
Response: TStrings;
begin
{ A TStringList is a TStrings descendant class
that is used to store and manipulate a list
of strings.
Instantiate a stringlist class to
hold the results of our HTTP GET }
Response := TStringList.Create;
try
// Try an HTTP GET request
if DoHTTPGET(host,res,Response) then
begin
{$IFDEF DEBUG}
{ Write the entire response to
the console window }
Writeln(Response.text);
{$ELSE}
{ Parse the response and write the
result to the console window }
Writeln(ParseResponse(Response));
{$ENDIF DEBUG}
end
else
Writeln('Error retrieving data');
finally
Response.Free;
end;
// Keep console window open
Readln;
end.
|
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Crystal | Crystal | require "http/client"
require "regex"
# Get the text from the internet
response = HTTP::Client.get "https://www.gutenberg.org/files/135/135-0.txt"
text = response.body
text
.downcase
.scan(/[a-zA-ZáéíóúÁÉÍÓÚâêôäüöàèìòùñ']+/)
.reduce({} of String => Int32) { |hash, match|
word = match[0]
hash[word] = hash.fetch(word, 0) + 1 # using fetch to set a default value (1) to the new found word
hash
}
.to_a # convert the returned hash to an array of tuples (String, Int32) -> {word, sum}
.sort { |a, b| b[1] <=> a[1] }[0..9] # sort and get the first 10 elements
.each_with_index(1) { |(word, n), i| puts "#{i} \t #{word} \t #{n}" } # print the result
|
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneously.
The cell transition rules are this:
Input State
Output State
Condition
empty
empty
electron head
electron tail
electron tail
conductor
conductor
electron head
if 1 or 2 cells in the neighborhood of the cell are in the state “electron head”
conductor
conductor
otherwise
Task
Create a program that reads a Wireworld program from a file and displays an animation of the processing. Here is a sample description file (using "H" for an electron head, "t" for a tail, "." for a conductor and a space for empty) you may wish to test with, which demonstrates two cycle-3 generators and an inhibit gate:
tH.........
. .
...
. .
Ht.. ......
While text-only implementations of this task are possible, mapping cells to pixels is advisable if you wish to be able to display large designs. The logic is not significantly more complex.
| #Go | Go | package main
import (
"bytes"
"fmt"
"io/ioutil"
"strings"
)
var rows, cols int // extent of input configuration
var rx, cx int // grid extent (includes border)
var mn []int // offsets of moore neighborhood
func main() {
// read input configuration from file
src, err := ioutil.ReadFile("ww.config")
if err != nil {
fmt.Println(err)
return
}
srcRows := bytes.Split(src, []byte{'\n'})
// compute package variables
rows = len(srcRows)
for _, r := range srcRows {
if len(r) > cols {
cols = len(r)
}
}
rx, cx = rows+2, cols+2
mn = []int{-cx-1, -cx, -cx+1, -1, 1, cx-1, cx, cx+1}
// allocate two grids and copy input into first grid
odd := make([]byte, rx*cx)
even := make([]byte, rx*cx)
for ri, r := range srcRows {
copy(odd[(ri+1)*cx+1:], r)
}
// run
for {
print(odd)
step(even, odd)
fmt.Scanln()
print(even)
step(odd, even)
fmt.Scanln()
}
}
func print(grid []byte) {
fmt.Println(strings.Repeat("__", cols))
fmt.Println()
for r := 1; r <= rows; r++ {
for c := 1; c <= cols; c++ {
if grid[r*cx+c] == 0 {
fmt.Print(" ")
} else {
fmt.Printf(" %c", grid[r*cx+c])
}
}
fmt.Println()
}
}
func step(dst, src []byte) {
for r := 1; r <= rows; r++ {
for c := 1; c <= cols; c++ {
x := r*cx + c
dst[x] = src[x]
switch dst[x] {
case 'H':
dst[x] = 't'
case 't':
dst[x] = '.'
case '.':
var nn int
for _, n := range mn {
if src[x+n] == 'H' {
nn++
}
}
if nn == 1 || nn == 2 {
dst[x] = 'H'
}
}
}
}
} |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Java | Java | import javax.swing.JFrame;
public class Main {
public static void main(String[] args) throws Exception {
JFrame w = new JFrame("Title");
w.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
w.setSize(800,600);
w.setVisible(true);
}
} |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #JavaScript | JavaScript | window.open("webpage.html", "windowname", "width=800,height=600");
|
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Icon_and_Unicon | Icon and Unicon |
procedure main(A)
ll := integer(A[1]) | 72
wordWrap(&input, ll)
end
procedure wordWrap(f, ll)
every (sep := "", s := "", w := words(f)) do
if w == "\n" then write(1(.s, s := sep := ""),"\n")
else if (*s + *w) >= ll then write(1(.s, s := w, sep := " "))
else (s ||:= .sep||("\n" ~== w), sep := " ")
if *s > 0 then write(s)
end
procedure words(f)
static wc
initial wc := &cset -- ' \t' # Loose definition of a 'word'...
while l := !f do {
l ? while tab(upto(wc)) do suspend tab(many(wc))\1
if *trim(l) = 0 then suspend "\n" # Paragraph boundary
}
end |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #R | R | library(XML)
char2xml <- function(names, remarks){
tt <- xmlHashTree()
head <- addNode(xmlNode("CharacterRemarks"), character(), tt)
node <- list()
for (i in 1:length(names)){
node[[i]] <- addNode(xmlNode("Character", attrs=c(name=names[i])), head, tt)
addNode(xmlTextNode(remarks[i]), node[[i]], tt)
}
return(tt)
}
output <- char2xml( names=c("April","Tam O'Shanter","Emily"),
remarks=c("Bubbly: I'm > Tam and <= Emily", 'Burns: "When chapman billies leave the street ..."', "Short & shrift") ) |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #Racket | Racket |
#lang racket
(require xml)
(define (make-character-xexpr characters remarks)
`(CharacterRemarks
,@(for/list ([character characters]
[remark remarks])
`(Character ((name ,character)) ,remark))))
(display-xml/content
(xexpr->xml
(make-character-xexpr
'("April" "Tam O'Shanter" "Emily")
'("Bubbly: I'm > Tam and <= Emily"
"Burns: \"When chapman billies leave the street ...\""
"Short & shrift"))))
|
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #OpenEdge_ABL.2FProgress_4GL | OpenEdge ABL/Progress 4GL |
/** ==== Definitions ===== **/
DEFINE VARIABLE chXMLString AS LONGCHAR NO-UNDO.
DEFINE TEMP-TABLE ttStudent NO-UNDO XML-NODE-NAME 'Student'
FIELD StudentName AS CHARACTER XML-NODE-TYPE 'attribute' XML-NODE-NAME 'Name' LABEL 'Name'
FIELD Gender AS CHARACTER XML-NODE-TYPE 'attribute' XML-NODE-NAME 'Gender' LABEL 'Gender'
FIELD DateOfBirth AS CHARACTER XML-NODE-TYPE 'attribute' XML-NODE-NAME 'DateOfBirth' LABEL 'Date Of Birth'.
DEFINE DATASET dsStudents XML-NODE-NAME 'Students' FOR ttStudent.
/** ==== Main block ====**/
/** ASSIGN the XML string with the XML data.. **/
chXMLString = '<Students>~
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />~
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />~
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />~
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">~
<Pet Type="dog" Name="Rover" />~
</Student>~
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />~
</Students>'.
/** Read the string into the dataset...**/
DATASET dsStudents:READ-XML('LONGCHAR', chXMLString, 'EMPTY',?,?).
/** Loop thought each temp-table record to produce the results...**/
FOR EACH ttStudent:
DISPLAY ttStudent.StudentName.
END.
|
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #OpenEdge.2FProgress | OpenEdge/Progress |
DEF VAR lcc AS LONGCHAR.
DEF VAR hxdoc AS HANDLE.
DEF VAR hxstudents AS HANDLE.
DEF VAR hxstudent AS HANDLE.
DEF VAR hxname AS HANDLE.
DEF VAR ii AS INTEGER EXTENT 2.
DEF VAR cstudents AS CHARACTER.
lcc = '<Students>'
+ '<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />'
+ '<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />'
+ '<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />'
+ '<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">'
+ '<Pet Type="dog" Name="Rover" />'
+ '</Student>'
+ '<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />'
+ '</Students>'.
CREATE X-DOCUMENT hxdoc.
hxdoc:LOAD( 'LONGCHAR', lcc, FALSE ).
DO ii[1] = 1 TO hxdoc:NUM-CHILDREN:
CREATE X-NODEREF hxstudents.
hxdoc:GET-CHILD( hxstudents, ii[1] ).
IF hxstudents:NAME = 'Students' THEN DO ii[2] = 1 TO hxstudents:NUM-CHILDREN:
CREATE X-NODEREF hxstudent.
hxstudents:GET-CHILD( hxstudent, ii[2] ).
IF hxstudent:NAME = 'Student' THEN
cstudents = cstudents + hxstudent:GET-ATTRIBUTE( 'Name' ) + '~n'.
DELETE OBJECT hxstudent.
END.
DELETE OBJECT hxstudents.
END.
DELETE OBJECT hxdoc.
MESSAGE cstudents VIEW-AS ALERT-BOX. |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #X86_Assembly | X86 Assembly |
section .text
global _start
_print:
mov ebx, 1
mov eax, 4
int 0x80
ret
_start:
;print out our byte array. ergo, String.
mov edx, sLen
mov ecx, sArray
call _print
mov edx, f_len
mov ecx, f_msg
call _print
mov edx, 6 ;our array members length.
xor ecx, ecx
mov ecx, 4
;turnicate through the array and print all it's members.
;At an offset of *4, each array member is referenced
;at 1,2,3 and so on.
_out_loops:
push ecx
mov ecx, [fArray+esi*4]
call _print
inc esi
pop ecx
loop _out_loops
mov edx, u_len
mov ecx, u_msg
call _print
;Let's populate 'uArray' with something from sArray.
;mov edi, uArray
mov ecx, 4
xor esi, esi
_read_loops:
push dword [fArray+esi*4]
pop dword [uArray+esi*4]
inc esi
loop _read_loops
mov ecx, 4
xor esi, esi
_out_loops2:
push ecx
mov ecx, [uArray+esi*4]
call _print
inc esi
pop ecx
loop _out_loops2
push 0x1
mov eax, 1
push eax
int 0x80
section .data
sArray db 'a','r','r','a','y','s',' ','a','r','e',' ','f','u','n',0xa
sLen equ $-sArray
crap1 db "crap1",0xa
crap2 db "crap2",0xa
crap3 db "crap3",0xa
crap4 db "crap4",0xa
fArray dd crap1,crap2
dd crap3,crap4
f_msg db "fArray contents",0xa,"----------------------",0xa
f_len equ $-f_msg
u_msg db "uArray now holds fArray contents.. dumping..",0xa,"----------------------",0xa
u_len equ $-u_msg
section .bss
uArray resd 1
resd 1
resd 1
resd 1
|
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #Octave | Octave | doors = false(100,1);
for i = 1:100
for j = i:i:100
doors(j) = !doors(j);
endfor
endfor
for i = 1:100
if ( doors(i) )
s = "open";
else
s = "closed";
endif
printf("%d %s\n", i, s);
endfor |
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[WeirdNumberQ, HasSumQ]
HasSumQ[n_Integer, xs_List] := HasSumHelperQ[n, ReverseSort[xs]]
HasSumHelperQ[n_Integer, xs_List] := Module[{h, t},
If[Length[xs] > 0,
h = First[xs];
t = Drop[xs, 1];
If[n < h,
HasSumHelperQ[n, t]
,
n == h \[Or] HasSumHelperQ[n - h, t] \[Or] HasSumHelperQ[n, t]
]
,
False
]
]
WeirdNumberQ[n_Integer] := Module[{divs},
divs = Most[Divisors[n]];
If[Total[divs] > n,
! HasSumQ[n, divs]
,
False
]
]
r = {};
n = 0;
While[
Length[r] < 25,
If[WeirdNumberQ[++n], AppendTo[r, n]]
]
Print[r] |
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Nim | Nim | import algorithm, math, strutils
func divisors(n: int): seq[int] =
var smallDivs = @[1]
for i in 2..sqrt(n.toFloat).int:
if n mod i == 0:
let j = n div i
smallDivs.add i
if i != j: result.add j
result.add reversed(smallDivs)
func abundant(n: int; divs: seq[int]): bool {.inline.}=
sum(divs) > n
func semiperfect(n: int; divs: seq[int]): bool =
if divs.len > 0:
let h = divs[0]
let t = divs[1..^1]
result = if n < h: semiperfect(n, t)
else: n == h or semiperfect(n - h, t) or semiperfect(n, t)
func sieve(limit: int): seq[bool] =
# False denotes abundant and not semi-perfect.
# Only interested in even numbers >= 2.
result.setLen(limit)
for i in countup(2, limit - 1, 2):
if result[i]: continue
let divs = divisors(i)
if not abundant(i, divs):
result[i] = true
elif semiperfect(i, divs):
for j in countup(i, limit - 1, i):
result[j] = true
const Max = 25
let w = sieve(17_000)
var list: seq[int]
echo "The first 25 weird numbers are:"
var n = 2
while list.len != Max:
if not w[n]: list.add n
inc n, 2
echo list.join(" ") |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #PicoLisp | PicoLisp | (de Lst
"***** * "
"* * * * * "
"* * **** **** * **** ****"
"***** * * * * * * * * * *"
"* * * * * * * * ****"
"* * * * * * * * * "
"* * * * * * * * * * "
"* * **** **** **** * **** * " )
(de transform (Lst A B)
(make
(chain (need (length Lst) " "))
(for (L (chop (car Lst)) L)
(ifn (= "*" (pop 'L))
(link " " " " " ")
(chain (need 3 A))
(when (sp? (car L))
(link B " " " ")
(pop 'L) ) ) ) ) )
(prinl (transform Lst "/" "\\"))
(mapc
'((X Y)
(mapc
'((A B)
(prin (if (sp? B) A B)) )
X
Y )
(prinl) )
(maplist '((X) (transform X "\\" "/")) Lst)
(maplist '((X) (transform X "/" "\\")) (cdr Lst)) )
(bye) |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #PureBasic | PureBasic | If OpenConsole()
PrintN(" ////\ ////\ ////| ")
PrintN(" //// \ __ //// \ __ |XX|_/ ")
PrintN(" //// /| | ////\ ////\//// |//// /| | //// | ////\ ////\ ")
PrintN("|XX| |X| ////\X| ////\// //// /||XX| |X| |//// /|| //// _| ////\ //// \ ")
PrintN("|XX| |X||XX| |X||XX| |/ |XX| |X||XX| |/ /|XX| |X||//// / |XX| | //// /\ |")
PrintN("|XX| |/ |XX| |X||XX| /|XX| |//|XX| \|XX|/// |XX| |/\ |XX| ||XX| |XX\|")
PrintN("|XX| /|XX| |X||XX| / |XX| //|XX| /| |//// |XX| ||XX| ||XX| | ")
PrintN("|$$| / |$$| |&||$$| | |$$| |&||$$| |&| |$$| /||\\\\/| ||$$| ||$$| |///|")
PrintN("|%%| | |%%| |i||%%| | |%%| |/ |%%| |i| |%%| |i|| |%%| ||%%| ||%%| |// |")
PrintN("|ii| | |ii| |/ |ii| | |ii| /|ii| |/ /|ii| \/|/ |ii| /|ii| ||ii| |/ / ")
PrintN("|::| | \\\\ /|::| | |::| / |::| / |::| / //// / |::| | \\\\ / ")
PrintN("|..| | \\\\/ |..|/ \\\\/ |..| / \\\\/ \\\\ / |..|/ \\\\/ ")
PrintN(" \\\\| \\\\/ ")
Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input()
CloseConsole()
EndIf |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #E | E | interp.waitAtTop(when (def html := <http://tycho.usno.navy.mil/cgi-bin/timer.pl>.getText()) -> {
def rx`(?s).*>(@time.*? UTC).*` := html
println(time)
}) |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #D | D | import std.algorithm : sort;
import std.array : appender, split;
import std.range : take;
import std.stdio : File, writefln, writeln;
import std.typecons : Tuple;
import std.uni : toLower;
//Container for a word and how many times it has been seen
alias Pair = Tuple!(string, "k", int, "v");
void main() {
int[string] wcnt;
//Read the file line by line
foreach (line; File("135-0.txt").byLine) {
//Split the words on whitespace
foreach (word; line.split) {
//Increment the times the word has been seen
wcnt[word.toLower.idup]++;
}
}
//Associative arrays cannot be sort, so put the key/value in an array
auto wb = appender!(Pair[]);
foreach(k,v; wcnt) {
wb.put(Pair(k,v));
}
Pair[] sw = wb.data.dup;
//Sort the array, and display the top ten values
writeln("Rank Word Frequency");
int rank=1;
foreach (word; sw.sort!"a.v>b.v".take(10)) {
writefln("%4s %-10s %9s", rank++, word.k, word.v);
}
} |
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneously.
The cell transition rules are this:
Input State
Output State
Condition
empty
empty
electron head
electron tail
electron tail
conductor
conductor
electron head
if 1 or 2 cells in the neighborhood of the cell are in the state “electron head”
conductor
conductor
otherwise
Task
Create a program that reads a Wireworld program from a file and displays an animation of the processing. Here is a sample description file (using "H" for an electron head, "t" for a tail, "." for a conductor and a space for empty) you may wish to test with, which demonstrates two cycle-3 generators and an inhibit gate:
tH.........
. .
...
. .
Ht.. ......
While text-only implementations of this task are possible, mapping cells to pixels is advisable if you wish to be able to display large designs. The logic is not significantly more complex.
| #Haskell | Haskell | import Data.List
import Control.Monad
import Control.Arrow
import Data.Maybe
states=" Ht."
shiftS=" t.."
borden bc xs = bs: (map (\x -> bc:(x++[bc])) xs) ++ [bs]
where r = length $ head xs
bs = replicate (r+2) bc
take3x3 = ap ((.). taken. length) (taken. length. head) `ap` borden '*'
where taken n = transpose. map (take n.map (take 3)).map tails
nwState xs | e =='.' && noH>0 && noH<3 = 'H'
| otherwise = shiftS !! (fromJust $ elemIndex e states)
where e = xs!!1!!1
noH = length $ filter (=='H') $ concat xs
runCircuit = iterate (map(map nwState).take3x3) |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Julia | Julia | # v0.6
using Tk
w = Toplevel("Example") |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Kotlin | Kotlin | import javax.swing.JFrame
fun main(args : Array<String>) {
JFrame("Title").apply {
setSize(800, 600)
defaultCloseOperation = JFrame.EXIT_ON_CLOSE
isVisible = true
}
} |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #IS-BASIC | IS-BASIC | 100 TEXT 80
110 CALL WRITE(12,68,0)
120 PRINT :CALL WRITE(10,70,1)
130 DEF WRITE(LEFTMARGIN,RIGHTMARGIN,JUSTIFIED)
140 STRING S$*254
150 RESTORE
160 PRINT TAB(LEFTMARGIN);CHR$(243);
170 PRINT TAB(RIGHTMARGIN-1);CHR$(251)
180 DO
190 READ IF MISSING EXIT DO:S$
200 PRINT S$;
210 LOOP
220 IF JUSTIFIED THEN PRINT CHR$(248) ! <- Extra credit :-)
230 PRINT
240 END DEF
250 DATA "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. "
260 DATA "Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, "
270 DATA "and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything."
|
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #J | J | ww =: 75&$: : wrap
wrap =: (] turn edges) ,&' '
turn =: LF"_`]`[}
edges =: (_1 + ] #~ 1 ,~ 2 >/\ |) [: +/\ #;.2 |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #Raku | Raku | use XML::Writer;
my @students =
[ 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] ]
;
my @lines = map { :Character[:name(.[0]), .[1]] }, @students;
say XML::Writer.serialize( CharacterRemarks => @lines ); |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #Oz | Oz | declare
[XMLParser] = {Module.link ['x-oz://system/xml/Parser.ozf']}
Parser = {New XMLParser.parser init}
Data =
"<Students>"
#" <Student Name=\"April\" Gender=\"F\" DateOfBirth=\"1989-01-02\" />"
#" <Student Name=\"Bob\" Gender=\"M\" DateOfBirth=\"1990-03-04\" />"
#" <Student Name=\"Chad\" Gender=\"M\" DateOfBirth=\"1991-05-06\" />"
#" <Student Name=\"Dave\" Gender=\"M\" DateOfBirth=\"1992-07-08\">"
#" <Pet Type=\"dog\" Name=\"Rover\" />"
#" </Student>"
#" <Student DateOfBirth=\"1993-09-10\" Gender=\"F\" Name=\"Émily\" />"
#"</Students>"
fun {IsStudentElement X}
case X of element(name:'Student' ...) then true
else false
end
end
fun {GetStudentName element(attributes:As ...)}
[NameAttr] = {Filter As fun {$ attribute(name:N ...)} N == 'Name' end}
in
NameAttr.value
end
[StudentsDoc] = {Parser parseVS(Data $)}
Students = {Filter StudentsDoc.children IsStudentElement}
StudentNames = {Map Students GetStudentName}
in
{ForAll StudentNames System.showInfo} |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #XBS | XBS | set Array = ["Hello","World"];
log(Array[0]);
Array.push("Test");
log(?Array);
log(Array[?Array-1]); |
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #Oforth | Oforth | : doors
| i j l |
100 false Array newWith dup ->l
100 loop: i [
i 100 i step: j [ l put ( j , j l at not ) ]
]
;
|
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Perl | Perl | use strict;
use feature 'say';
use List::Util 'sum';
use POSIX 'floor';
use Algorithm::Combinatorics 'subsets';
use ntheory <is_prime divisors>;
sub abundant {
my($x) = @_;
my $s = sum( my @l = is_prime($x) ? 1 : grep { $x != $_ } divisors($x) );
$s > $x ? ($s, sort { $b <=> $a } @l) : ();
}
my(@weird,$n);
while () {
$n++;
my ($sum, @div) = abundant($n);
next unless $sum; # Weird number must be abundant, skip it if it isn't.
next if $sum / $n > 1.1; # There aren't any weird numbers with a sum:number ratio greater than 1.08 or so.
if ($n >= 10430 and (! int $n%70) and is_prime(int $n/70)) {
# It's weird. All numbers of the form 70 * (a prime 149 or larger) are weird
} else {
my $next;
my $l = shift @div;
my $iter = subsets(\@div);
while (my $s = $iter->next) {
++$next and last if sum(@$s) == $n - $l;
}
next if $next;
}
push @weird, $n;
last if @weird == 25;
}
say "The first 25 weird numbers:\n" . join ' ', @weird; |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Python | Python | py = '''\
##### # # ##### # # #### # #
# # # # # # # # # ## #
# # # # ###### # # # # #
##### # # # # # # # # #
# # # # # # # # ##
# # # # # #### # #
'''
lines = py.replace('#', '<<<').replace(' ','X').replace('X', ' ').replace('\n', ' Y').replace('< ', '<>').split('Y')
for i, l in enumerate(lines):
print( ' ' * (len(lines) - i) + l) |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #Erlang | Erlang | -module(scraping).
-export([main/0]).
-define(Url, "http://tycho.usno.navy.mil/cgi-bin/timer.pl").
-define(Match, "<BR>(.+ UTC)").
main() ->
inets:start(),
{ok, {_Status, _Header, HTML}} = httpc:request(?Url),
{match, [Time]} = re:run(HTML, ?Match, [{capture, all_but_first, binary}]),
io:format("~s~n",[Time]). |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Delphi | Delphi |
program Word_frequency;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.IOUtils,
System.Generics.Collections,
System.Generics.Defaults,
System.RegularExpressions;
type
TWords = TDictionary<string, Integer>;
TFreqPair = TPair<string, Integer>;
TFreq = TArray<TFreqPair>;
function CreateValueCompare: IComparer<TFreqPair>;
begin
Result := TComparer<TFreqPair>.Construct(
function(const Left, Right: TFreqPair): Integer
begin
Result := Right.Value - Left.Value;
end);
end;
function WordFrequency(const Text: string): TFreq;
var
words: TWords;
match: TMatch;
w: string;
begin
words := TWords.Create();
match := TRegEx.Match(Text, '\w+');
while match.Success do
begin
w := match.Value;
if words.ContainsKey(w) then
words[w] := words[w] + 1
else
words.Add(w, 1);
match := match.NextMatch();
end;
Result := words.ToArray;
words.Free;
TArray.Sort<TFreqPair>(Result, CreateValueCompare);
end;
var
Text: string;
rank: integer;
Freq: TFreq;
w: TFreqPair;
begin
Text := TFile.ReadAllText('135-0.txt').ToLower();
Freq := WordFrequency(Text);
Writeln('Rank Word Frequency');
Writeln('==== ==== =========');
for rank := 1 to 10 do
begin
w := Freq[rank - 1];
Writeln(format('%2d %6s %5d', [rank, w.Key, w.Value]));
end;
readln;
end.
|
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneously.
The cell transition rules are this:
Input State
Output State
Condition
empty
empty
electron head
electron tail
electron tail
conductor
conductor
electron head
if 1 or 2 cells in the neighborhood of the cell are in the state “electron head”
conductor
conductor
otherwise
Task
Create a program that reads a Wireworld program from a file and displays an animation of the processing. Here is a sample description file (using "H" for an electron head, "t" for a tail, "." for a conductor and a space for empty) you may wish to test with, which demonstrates two cycle-3 generators and an inhibit gate:
tH.........
. .
...
. .
Ht.. ......
While text-only implementations of this task are possible, mapping cells to pixels is advisable if you wish to be able to display large designs. The logic is not significantly more complex.
| #Icon_and_Unicon | Icon and Unicon | link graphics
$define EDGE -1
$define EMPTY 0
$define HEAD 1
$define TAIL 2
$define COND 3
global Colours,Width,Height,World,oldWorld
procedure main() # wire world modified from forestfire
Height := 400 # Window height
Width := 400 # Window width
Rounds := 500 # max Rounds
Delay := 5 # Runout Delay
setup_world(read_world())
every round := 1 to Rounds do {
show_world()
if \runout then
delay(Delay)
else
case Event() of {
"q" : break # q = quit
"r" : runout := 1 # r = run w/o stepping
"s" : WriteImage("Wireworld-"||round) # save
}
evolve_world()
}
WDone()
end
procedure read_world() #: for demo in place of reading
return [ "tH.........",
". .",
" ...",
". .",
"Ht.. ......"]
end
procedure setup_world(L) #: setup the world
Colours := table() # define colours
Colours[EDGE] := "grey"
Colours[EMPTY] := "black"
Colours[HEAD] := "blue"
Colours[TAIL] := "red"
Colours[COND] := "yellow"
States := table()
States["t"] := TAIL
States["H"] := HEAD
States[" "] := EMPTY
States["."] := COND
WOpen("label=Wireworld", "bg=black",
"size=" || Width+2 || "," || Height+2) | # add for border
stop("Unable to open Window")
every !(World := list(Height)) := list(Width,EMPTY) # default
every ( World[1,1 to Width] | World[Height,1 to Width] |
World[1 to Height,1] | World[1 to Height,Width] ) := EDGE
every r := 1 to *L & c := 1 to *L[r] do { # setup read in program
World[r+1, c+1] := States[L[r,c]]
}
end
procedure show_world() #: show World - drawn changes only
every r := 2 to *World-1 & c := 2 to *World[r]-1 do
if /oldWorld | oldWorld[r,c] ~= World[r,c] then {
WAttrib("fg=" || Colours[tr := World[r,c]])
DrawPoint(r,c)
}
end
procedure evolve_world() #: evolve world
old := oldWorld := list(*World) # freeze copy
every old[i := 1 to *World] := copy(World[i]) # deep copy
every r := 2 to *World-1 & c := 2 to *World[r]-1 do
World[r,c] := case old[r,c] of { # apply rules
# EMPTY : EMPTY
HEAD : TAIL
TAIL : COND
COND : {
i := 0
every HEAD = ( old[r-1,c-1 to c+1] | old[r,c-1|c+1] | old[r+1,c-1 to c+1] ) do i +:= 1
if i := 1 | 2 then HEAD
}
}
end |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Liberty_BASIC | Liberty BASIC | nomainwin
open "GUI Window" for window as #1
wait
|
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Lingo | Lingo | win = window().new("New Window")
w = 320
h = 240
firstScreen = _system.deskTopRectList[1]
x = firstScreen.width/2 - w/2
y = firstScreen.height/2- h/2
win.rect = rect(x,y,x+w,y+h)
-- Director needs a binary movie file (*.dir) for opening new windows. But this
-- movie file can be totally empty, and if it's write protected in the filesystem,
-- it can be re-used for multiple windows.
win.filename = _movie.path & "empty.dir"
win.open() |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #Java | Java |
package rosettacode;
import java.util.StringTokenizer;
public class WordWrap
{
int defaultLineWidth=80;
int defaultSpaceWidth=1;
void minNumLinesWrap(String text)
{
minNumLinesWrap(text,defaultLineWidth);
}
void minNumLinesWrap(String text,int LineWidth)
{
StringTokenizer st=new StringTokenizer(text);
int SpaceLeft=LineWidth;
int SpaceWidth=defaultSpaceWidth;
while(st.hasMoreTokens())
{
String word=st.nextToken();
if((word.length()+SpaceWidth)>SpaceLeft)
{
System.out.print("\n"+word+" ");
SpaceLeft=LineWidth-word.length();
}
else
{
System.out.print(word+" ");
SpaceLeft-=(word.length()+SpaceWidth);
}
}
}
public static void main(String[] args)
{
WordWrap now=new WordWrap();
String wodehouse="Old Mr MacFarland (_said Henry_) started the place fifteen years ago. He was a widower with one son and what you might call half a daughter. That's to say, he had adopted her. Katie was her name, and she was the child of a dead friend of his. The son's name was Andy. A little freckled nipper he was when I first knew him--one of those silent kids that don't say much and have as much obstinacy in them as if they were mules. Many's the time, in them days, I've clumped him on the head and told him to do something; and he didn't run yelling to his pa, same as most kids would have done, but just said nothing and went on not doing whatever it was I had told him to do. That was the sort of disposition Andy had, and it grew on him. Why, when he came back from Oxford College the time the old man sent for him--what I'm going to tell you about soon--he had a jaw on him like the ram of a battleship. Katie was the kid for my money. I liked Katie. We all liked Katie.";
System.out.println("DEFAULT:");
now.minNumLinesWrap(wodehouse);
System.out.println("\n\nLINEWIDTH=120");
now.minNumLinesWrap(wodehouse,120);
}
}
|
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #Rascal | Rascal | import Prelude;
import lang::xml::DOM;
list[str] charnames = ["April", "Tam O\'Shanter", "Emily"];
list[str] remarks = ["Bubbly: I\'m \> Tam and \<= Emily", "Burns: \"When chapman billies leave the street ...\"", "Short & shrift"];
public void xmloutput(list[str] n,list[str] r){
if(size(n) != size(r)){
throw "n and r should be of the same size";
}
else{
characters = [element(none(),"Character",[attribute(none(),"name",n[i]), charData(r[i])]),charData("\n")| i <- [0..size(n)-1]];
x = document(element(none(),"CharacterRemarks",characters));
return println(xmlPretty(x));
}
} |
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #REXX | REXX | /*REXX program creates an HTML (XML) list of character names and corresponding remarks. */
charname. =
charname.1 = "April"
charname.2 = "Tam O'Shanter"
charname.3 = "Emily"
do i=1 while charname.i\==''
say 'charname' i '=' charname.i
end /*i*/; say
remark. =
remark.1 = "I'm > Tam and <= Emily"
remark.2 = "When chapman billies leave the street ..."
remark.3 = "Short & shift"
do k=1 while remark.k\==''
say ' remark' k '=' remark.k
end /*k*/; say
items = 0
header = 'CharacterRemarks'
header = header'>'
do j=1 while charname.j\==''
_=charname.j
if j==1 then call create '<'header
call create ' <Character name="' ||,
char2xml(_)'">"' ||,
char2xml(remark.j)'"</Character>'
end /*j*/
if create.0\==0 then call create '</'header
do m=1 for create.0
say create.m /*display the Mth entry to terminal. */
end /*m*/
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
char2xml: procedure; parse arg $
amper = pos('&', $)\==0 /* & has to be treated special. */
semi = pos(';', $)\==0 /* ; " " " " " */
#=0 /* [↓] find a free/unused character···*/
if amper then do /* ··· and translate freely. */
do j=0 for 255; ?=d2c(j); if pos(?, $)==0 then leave
end /*j*/
$=translate($, ?, "&"); #= j + 1
end
/* [↓] find a free/unused character···*/
if semi then do /* ··· and translate freely. */
do k=# for 255; ?=d2c(k); if pos(?, $)==0 then leave
end /*k*/
$=translate($, ?, ";")
end
/*───── Following are most of the characters in the DOS (or DOS Windows) codepage 437 ──────────*/
$=XML_('â',"ETH") ; $=XML_('ƒ',"fnof") ; $=XML_('═',"boxH") ; $=XML_('♥',"hearts")
$=XML_('â','#x00e2') ; $=XML_('á',"aacute"); $=XML_('╬',"boxVH") ; $=XML_('♦',"diams")
$=XML_('â','#x00e9') ; $=XML_('á','#x00e1'); $=XML_('╧',"boxHu") ; $=XML_('♣',"clubs")
$=XML_('ä',"auml") ; $=XML_('í',"iacute"); $=XML_('╨',"boxhU") ; $=XML_('♠',"spades")
$=XML_('ä','#x00e4') ; $=XML_('í','#x00ed'); $=XML_('╤',"boxHd") ; $=XML_('♂',"male")
$=XML_('à',"agrave") ; $=XML_('ó',"oacute"); $=XML_('╥',"boxhD") ; $=XML_('♀',"female")
$=XML_('à','#x00e0') ; $=XML_('ó','#x00f3'); $=XML_('╙',"boxUr") ; $=XML_('☼',"#x263c")
$=XML_('å',"aring") ; $=XML_('ú',"uacute"); $=XML_('╘',"boxuR") ; $=XML_('↕',"UpDownArrow")
$=XML_('å','#x00e5') ; $=XML_('ú','#x00fa'); $=XML_('╒',"boxdR") ; $=XML_('¶',"para")
$=XML_('ç',"ccedil") ; $=XML_('ñ',"ntilde"); $=XML_('╓',"boxDr") ; $=XML_('§',"sect")
$=XML_('ç','#x00e7') ; $=XML_('ñ','#x00f1'); $=XML_('╫',"boxVh") ; $=XML_('↑',"uarr")
$=XML_('ê',"ecirc") ; $=XML_('Ñ',"Ntilde"); $=XML_('╪',"boxvH") ; $=XML_('↑',"uparrow")
$=XML_('ê','#x00ea') ; $=XML_('Ñ','#x00d1'); $=XML_('┘',"boxul") ; $=XML_('↑',"ShortUpArrow")
$=XML_('ë',"euml") ; $=XML_('¿',"iquest"); $=XML_('┌',"boxdr") ; $=XML_('↓',"darr")
$=XML_('ë','#x00eb') ; $=XML_('⌐',"bnot") ; $=XML_('█',"block") ; $=XML_('↓',"downarrow")
$=XML_('è',"egrave") ; $=XML_('¬',"not") ; $=XML_('▄',"lhblk") ; $=XML_('↓',"ShortDownArrow")
$=XML_('è','#x00e8') ; $=XML_('½',"frac12"); $=XML_('▀',"uhblk") ; $=XML_('←',"larr")
$=XML_('ï',"iuml") ; $=XML_('½',"half") ; $=XML_('α',"alpha") ; $=XML_('←',"leftarrow")
$=XML_('ï','#x00ef') ; $=XML_('¼',"frac14"); $=XML_('ß',"beta") ; $=XML_('←',"ShortLeftArrow")
$=XML_('î',"icirc") ; $=XML_('¡',"iexcl") ; $=XML_('ß',"szlig") ; $=XML_('1c'x,"rarr")
$=XML_('î','#x00ee') ; $=XML_('«',"laqru") ; $=XML_('ß','#x00df') ; $=XML_('1c'x,"rightarrow")
$=XML_('ì',"igrave") ; $=XML_('»',"raqru") ; $=XML_('Γ',"Gamma") ; $=XML_('1c'x,"ShortRightArrow")
$=XML_('ì','#x00ec') ; $=XML_('░',"blk12") ; $=XML_('π',"pi") ; $=XML_('!',"excl")
$=XML_('Ä',"Auml") ; $=XML_('▒',"blk14") ; $=XML_('Σ',"Sigma") ; $=XML_('"',"apos")
$=XML_('Ä','#x00c4') ; $=XML_('▓',"blk34") ; $=XML_('σ',"sigma") ; $=XML_('$',"dollar")
$=XML_('Å',"Aring") ; $=XML_('│',"boxv") ; $=XML_('µ',"mu") ; $=XML_("'","quot")
$=XML_('Å','#x00c5') ; $=XML_('┤',"boxvl") ; $=XML_('τ',"tau") ; $=XML_('*',"ast")
$=XML_('É',"Eacute") ; $=XML_('╡',"boxvL") ; $=XML_('Φ',"phi") ; $=XML_('/',"sol")
$=XML_('É','#x00c9') ; $=XML_('╢',"boxVl") ; $=XML_('Θ',"Theta") ; $=XML_(':',"colon")
$=XML_('æ',"aelig") ; $=XML_('╖',"boxDl") ; $=XML_('δ',"delta") ; $=XML_('<',"lt")
$=XML_('æ','#x00e6') ; $=XML_('╕',"boxdL") ; $=XML_('∞',"infin") ; $=XML_('=',"equals")
$=XML_('Æ',"AElig") ; $=XML_('╣',"boxVL") ; $=XML_('φ',"Phi") ; $=XML_('>',"gt")
$=XML_('Æ','#x00c6') ; $=XML_('║',"boxV") ; $=XML_('ε',"epsilon") ; $=XML_('?',"quest")
$=XML_('ô',"ocirc") ; $=XML_('╗',"boxDL") ; $=XML_('∩',"cap") ; $=XML_('_',"commat")
$=XML_('ô','#x00f4') ; $=XML_('╝',"boxUL") ; $=XML_('≡',"equiv") ; $=XML_('[',"lbrack")
$=XML_('ö',"ouml") ; $=XML_('╜',"boxUl") ; $=XML_('±',"plusmn") ; $=XML_('\',"bsol")
$=XML_('ö','#x00f6') ; $=XML_('╛',"boxuL") ; $=XML_('±',"pm") ; $=XML_(']',"rbrack")
$=XML_('ò',"ograve") ; $=XML_('┐',"boxdl") ; $=XML_('±',"PlusMinus") ; $=XML_('^',"Hat")
$=XML_('ò','#x00f2') ; $=XML_('└',"boxur") ; $=XML_('≥',"ge") ; $=XML_('`',"grave")
$=XML_('û',"ucirc") ; $=XML_('┴',"bottom"); $=XML_('≤',"le") ; $=XML_('{',"lbrace")
$=XML_('û','#x00fb') ; $=XML_('┴',"boxhu") ; $=XML_('÷',"div") ; $=XML_('{',"lcub")
$=XML_('ù',"ugrave") ; $=XML_('┬',"boxhd") ; $=XML_('÷',"divide") ; $=XML_('|',"vert")
$=XML_('ù','#x00f9') ; $=XML_('├',"boxvr") ; $=XML_('≈',"approx") ; $=XML_('|',"verbar")
$=XML_('ÿ',"yuml") ; $=XML_('─',"boxh") ; $=XML_('∙',"bull") ; $=XML_('}',"rbrace")
$=XML_('ÿ','#x00ff') ; $=XML_('┼',"boxvh") ; $=XML_('°',"deg") ; $=XML_('}',"rcub")
$=XML_('Ö',"Ouml") ; $=XML_('╞',"boxvR") ; $=XML_('·',"middot") ; $=XML_('Ç',"Ccedil")
$=XML_('Ö','#x00d6') ; $=XML_('╟',"boxVr") ; $=XML_('·',"middledot") ; $=XML_('Ç','#x00c7')
$=XML_('Ü',"Uuml") ; $=XML_('╚',"boxUR") ; $=XML_('·',"centerdot") ; $=XML_('ü',"uuml")
$=XML_('Ü','#x00dc') ; $=XML_('╔',"boxDR") ; $=XML_('·',"CenterDot") ; $=XML_('ü','#x00fc')
$=XML_('¢',"cent") ; $=XML_('╩',"boxHU") ; $=XML_('√',"radic") ; $=XML_('é',"eacute")
$=XML_('£',"pound") ; $=XML_('╦',"boxHD") ; $=XML_('²',"sup2") ; $=XML_('é','#x00e9')
$=XML_('¥',"yen") ; $=XML_('╠',"boxVR") ; $=XML_('■',"square ") ; $=XML_('â',"acirc")
if amper then $=xml_(?, "amp") /*Was there an ampersand? Translate it*/
if semi then $=xml_(??, "semi") /* " " " semicolon? " "*/
return $
/*──────────────────────────────────────────────────────────────────────────────────────*/
create: items= items + 1 /*bump the count of items in the list. */
create.items= arg(1) /*add item to the CREATE list. */
create.0 = items /*indicate how many items in the list. */
return
/*──────────────────────────────────────────────────────────────────────────────────────*/
xml_: parse arg _ /*make an XML entity (&xxxx;) */
if pos(_, $)\==0 then return changestr(_, $, "&"arg(2)";")
return $ |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #Perl | Perl | use utf8;
use XML::Simple;
my $ref = XMLin('<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>');
print join( "\n", map { $_->{'Name'} } @{$ref->{'Student'}}); |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #XLISP | XLISP | [1] (define a (make-vector 10)) ; vector of 10 elements initialized to the empty list
A
[2] (define b (make-vector 10 5)) ; vector of 10 elements initialized to 5
B
[3] (define c #(1 2 3 4 5 6 7 8 9 10)) ; vector literal
C
[4] (vector-ref c 3) ; retrieve a value -- NB. indexed from 0
4
[5] (vector-set! a 5 1) ; set a_5 to 1
1
[6] (define d (make-array 5 6 7)) ; 3-dimensional array of size 5 by 6 by 7
D
[7] (array-set! d 1 2 3 10) ; set d_1,2,3 to 10 -- NB. still indexed from 0
10
[8] (array-ref d 1 2 3) ; and get the value of d_1,2,3
10 |
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #Ol | Ol |
(define (flip doors every)
(map (lambda (door num)
(mod (+ door (if (eq? (mod num every) 0) 1 0)) 2))
doors
(iota (length doors) 1)))
(define doors
(let loop ((doors (repeat 0 100)) (n 1))
(if (eq? n 100)
doors
(loop (flip doors n) (+ n 1)))))
(print "100th doors: " doors)
|
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Phix | Phix | with javascript_semantics
function abundant(integer n, sequence divs)
return sum(divs) > n
end function
function semiperfect(integer n, sequence divs)
if length(divs)=0 then return false end if
integer h = divs[1]; divs = divs[2..$]
return n=h
or (n>h and semiperfect(n-h, divs))
or semiperfect(n, divs)
end function
function sieve(integer limit)
-- true denotes abundant and not semi-perfect.
-- only interested in even numbers >= 2
sequence wierd := repeat(true,limit)
for j=6 to limit by 6 do
-- eliminate multiples of 3
wierd[j] = false
end for
for i=2 to limit by 2 do
if wierd[i] then
sequence divs := factors(i,-1)
if not abundant(i,divs) then
wierd[i] = false
elsif semiperfect(i,divs) then
for j=i to limit by i do wierd[j] = false end for
end if
end if
end for
return wierd
end function
--constant MAX = 25, sieve_limit = 16313
constant MAX = 50, sieve_limit = 26533
sequence wierd := sieve(sieve_limit), res = {}
for i=2 to sieve_limit by 2 do
if wierd[i] then
res &= i
if length(res)=MAX then exit end if
end if
end for
printf(1,"%s\n",{join(shorten(res,"weird numbers",5,"%d"))})
|
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Quackery | Quackery | say " ________ ___ ___ ________ ________ ___ __ _______ ________ ___ ___" cr
say "|\ __ \|\ \|\ \|\ __ \|\ ____\|\ \|\ \ |\ ___ \ |\ __ \|\ \ / /|" cr
say "\ \ \|\ \ \ \ \ \ \ \|\ \ \ \___|\ \ \/ /|\ \ __/|\ \ \|\ \ \ \/ / /" cr
say " \ \ \ \ \ \ \ \ \ \ __ \ \ \ \ \ ___ \ \ \_|/ \ \ _ _\ \ / /" cr
say " \ \ \_\ \ \ \_\ \ \ \ \ \ \ \____\ \ \\ \ \ \ \__\_\ \ \\ \ / / /" cr
say " \ \_____ \ \_______\ \__\ \__\ \_______\ \__\\ \__\ \_______\ \__\\ _\ / /" cr
say " \|___| \ \|_______|\|__|\|__|\|_______|\|__| \|__|\|_______|\|__|\|__| / /" cr
say " \ \ \_______________________________________________________/ / /" cr
say " \ \____________________________________________________________/ /" cr
say " \|____________________________________________________________|/" cr |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Racket | Racket |
#lang racket/gui
;; Get the language name
(define str (cadr (regexp-match #rx"Welcome to (.*?) *v[0-9.]+\n*$" (banner))))
;; Font to use
(define font (make-object font% 12 "MiscFixed" 'decorative 'normal 'bold))
;; (get-face-list) -> get a list of faces to try in the above
;; Calculate the needed size (leave space for a drop-down shadow)
(define-values [W H]
(let ([bdc (make-object bitmap-dc% (make-object bitmap% 1 1 #t))])
(call-with-values
(λ() (send* bdc (set-font font) (get-text-extent str font)))
(λ(w h _1 _2) (values (+ 2 (inexact->exact (round w)))
(+ 2 (inexact->exact (round h))))))))
;; Draw the text
(define bmp (make-bitmap W H #t))
(define dc (send bmp make-dc))
(send* dc (set-font font) (draw-text str 2 0))
;; Grab the pixels as a string, 3d-ed with "/"s
(define scr
(let* ([size (* W H 4)] [buf (make-bytes size)])
(send bmp get-argb-pixels 0 0 W H buf)
(define scr (make-string (* (add1 W) (add1 H)) #\space))
(for ([i (in-range 0 size 4)] [j (* W H)]
#:unless (zero? (bytes-ref buf i)))
(string-set! scr j #\@)
(for ([k (list j (+ j W -1))] [c "/."] #:when #t
[k (list (- k 1) (+ k W) (+ k W -1))]
#:when (and (< -1 k (string-length scr))
(member (string-ref scr k) '(#\space #\.))))
(string-set! scr k c)))
scr))
;; Show it, dropping empty lines
(let ([lines (for/list ([y H]) (substring scr (* y W) (* (add1 y) W)))])
(define (empty? l) (not (regexp-match #rx"[^ ]" l)))
(for ([line (dropf-right (dropf lines empty?) empty?)])
(displayln (string-trim line #:left? #f))))
|
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #F.23 | F# |
open System
open System.Net
open System.Text.RegularExpressions
async {
use wc = new WebClient()
let! html = wc.AsyncDownloadString(Uri("http://tycho.usno.navy.mil/cgi-bin/timer.pl"))
return Regex.Match(html, @"<BR>(.+ UTC)").Groups.[1].Value
}
|> Async.RunSynchronously
|> printfn "%s"
|
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #Factor | Factor | USING: http.client io sequences ;
"http://tycho.usno.navy.mil/cgi-bin/timer.pl" http-get nip
[ "UTC" swap start [ 9 - ] [ 1 - ] bi ] keep subseq print |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Underscores, accented letters, apostrophes, hyphens, and other special characters can be handled at your discretion.
You may treat a compound word like well-dressed as either one word or two.
The word it's could also be one or two words as you see fit.
You may also choose not to support non US-ASCII characters.
Assume words will not span multiple lines.
Don't worry about normalization of word spelling differences.
Treat color and colour as two distinct words.
Uppercase letters are considered equivalent to their lowercase counterparts.
Words of equal frequency can be listed in any order.
Feel free to explicitly state the thoughts behind the program decisions.
Show example output using Les Misérables from Project Gutenberg as the text file input and display the top 10 most used words.
History
This task was originally taken from programming pearls from Communications of the ACM June 1986 Volume 29 Number 6
where this problem is solved by Donald Knuth using literate programming and then critiqued by Doug McIlroy,
demonstrating solving the problem in a 6 line Unix shell script (provided as an example below).
References
McIlroy's program
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #F.23 | F# |
open System.IO
open System.Text.RegularExpressions
let g=Regex("[A-Za-zÀ-ÿ]+").Matches(File.ReadAllText "135-0.txt")
[for n in g do yield n.Value.ToLower()]|>List.countBy(id)|>List.sortBy(fun n->(-(snd n)))|>List.take 10|>List.iter(fun n->printfn "%A" n)
|
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneously.
The cell transition rules are this:
Input State
Output State
Condition
empty
empty
electron head
electron tail
electron tail
conductor
conductor
electron head
if 1 or 2 cells in the neighborhood of the cell are in the state “electron head”
conductor
conductor
otherwise
Task
Create a program that reads a Wireworld program from a file and displays an animation of the processing. Here is a sample description file (using "H" for an electron head, "t" for a tail, "." for a conductor and a space for empty) you may wish to test with, which demonstrates two cycle-3 generators and an inhibit gate:
tH.........
. .
...
. .
Ht.. ......
While text-only implementations of this task are possible, mapping cells to pixels is advisable if you wish to be able to display large designs. The logic is not significantly more complex.
| #J | J | circ0=:}: ] ;. _1 LF, 0 : 0
tH........
. .
...
. .
Ht.. .....
) |
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Lua | Lua | local iup = require "iuplua"
iup.dialog{
title = "Window";
iup.vbox{
margin = "10x10";
iup.label{title = "A window"}
}
}:show()
iup.MainLoop()
|
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #M2000_Interpreter | M2000 Interpreter |
Module DisplayWindow {
Declare MyForm Form
Method MyForm,"Show",1
}
DisplayWindow
|
http://rosettacode.org/wiki/Window_creation | Window creation | Display a GUI window. The window need not have any contents, but should respond to requests to be closed.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | CreateDocument[] |
http://rosettacode.org/wiki/Word_wrap | Word wrap | Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column.
Basic task
The basic task is to wrap a paragraph of text in a simple way in your language.
If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
If your language provides this, you get easy extra credit,
but you must reference documentation indicating that the algorithm
is something better than a simple minimum length algorithm.
If you have both basic and extra credit solutions, show an example where
the two algorithms give different results.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurrences of a substring
Count how many vowels and consonants occur in a string
Remove/replace
XXXX redacted
Conjugate a Latin verb
Remove vowels from a string
String interpolation (included)
Strip block comments
Strip comments from a string
Strip a set of characters from a string
Strip whitespace from a string -- top and tail
Strip control codes and extended characters from a string
Anagrams/Derangements/shuffling
Word wheel
ABC problem
Sattolo cycle
Knuth shuffle
Ordered words
Superpermutation minimisation
Textonyms (using a phone text pad)
Anagrams
Anagrams/Deranged anagrams
Permutations/Derangements
Find/Search/Determine
ABC words
Odd words
Word ladder
Semordnilap
Word search
Wordiff (game)
String matching
Tea cup rim text
Alternade words
Changeable words
State name puzzle
String comparison
Unique characters
Unique characters in each string
Extract file extension
Levenshtein distance
Palindrome detection
Common list elements
Longest common suffix
Longest common prefix
Compare a list of strings
Longest common substring
Find common directory path
Words from neighbour ones
Change e letters to i in words
Non-continuous subsequences
Longest common subsequence
Longest palindromic substrings
Longest increasing subsequence
Words containing "the" substring
Sum of the digits of n is substring of n
Determine if a string is numeric
Determine if a string is collapsible
Determine if a string is squeezable
Determine if a string has all unique characters
Determine if a string has all the same characters
Longest substrings without repeating characters
Find words which contains all the vowels
Find words which contains most consonants
Find words which contains more than 3 vowels
Find words which first and last three letters are equals
Find words which odd letters are consonants and even letters are vowels or vice_versa
Formatting
Substring
Rep-string
Word wrap
String case
Align columns
Literals/String
Repeat a string
Brace expansion
Brace expansion using ranges
Reverse a string
Phrase reversals
Comma quibbling
Special characters
String concatenation
Substring/Top and tail
Commatizing numbers
Reverse words in a string
Suffixation of decimal numbers
Long literals, with continuations
Numerical and alphabetical suffixes
Abbreviations, easy
Abbreviations, simple
Abbreviations, automatic
Song lyrics/poems/Mad Libs/phrases
Mad Libs
Magic 8-ball
99 Bottles of Beer
The Name Game (a song)
The Old lady swallowed a fly
The Twelve Days of Christmas
Tokenize
Text between
Tokenize a string
Word break problem
Tokenize a string with escaping
Split a character string based on change of character
Sequences
Show ASCII table
De Bruijn sequences
Self-referential sequences
Generate lower case ASCII alphabet
| #JavaScript | JavaScript |
function wrap (text, limit) {
if (text.length > limit) {
// find the last space within limit
var edge = text.slice(0, limit).lastIndexOf(' ');
if (edge > 0) {
var line = text.slice(0, edge);
var remainder = text.slice(edge + 1);
return line + '\n' + wrap(remainder, limit);
}
}
return text;
}
|
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 the function with the three names of:
April
Tam O'Shanter
Emily
And three remarks of:
Bubbly: I'm > Tam and <= Emily
Burns: "When chapman billies leave the street ..."
Short & shrift
Should produce the XML (but not necessarily with the indentation):
<CharacterRemarks>
<Character name="April">Bubbly: I'm > Tam and <= Emily</Character>
<Character name="Tam O'Shanter">Burns: "When chapman billies leave the street ..."</Character>
<Character name="Emily">Short & shrift</Character>
</CharacterRemarks>
The document may include an <?xml?> declaration and document type declaration, but these are optional. If attempting this task by direct string manipulation, the implementation must include code to perform entity substitution for the characters that have entities defined in the XML 1.0 specification.
Note: the example is chosen to show correct escaping of XML strings.
Note too that although the task is written to take two lists of corresponding data, a single mapping/hash/dictionary of names to remarks is also acceptable.
Note to editors: Program output with escaped characters will be viewed as the character on the page so you need to 'escape-the-escapes' to make the RC entry display what would be shown in a plain text viewer (See this).
Alternately, output can be placed in <lang xml></lang> tags without any special treatment.
| #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 |name, remark|
root.add_element("Character", {'Name' => name}).add_text(remark)
end
# output with indentation
doc.write($stdout, 2) |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
Expected Output
April
Bob
Chad
Dave
Émily
| #Phix | Phix | with javascript_semantics
include builtins/xml.e
constant xml = """
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" />
<Student Name="Chad" Gender="M" DateOfBirth="1991-05-06" />
<Student Name="Dave" Gender="M" DateOfBirth="1992-07-08">
<Pet Type="dog" Name="Rover" />
</Student>
<Student DateOfBirth="1993-09-10" Gender="F" Name="Émily" />
</Students>
"""
sequence x = xml_parse(xml)
procedure traverse(sequence x)
if x[XML_TAGNAME]="Student" then
puts(1,xml_get_attribute(x,"Name"),false)
puts(1,"\n")
else
x = x[XML_CONTENTS]
if not string(x) then
for i=1 to length(x) do
traverse(x[i])
end for
end if
end if
end procedure
traverse(x[XML_CONTENTS])
|
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available, show both fixed-length arrays and
dynamic arrays, pushing a value into it).
Please discuss at Village Pump: Arrays.
Please merge code in from these obsolete tasks:
Creating an Array
Assigning Values to an Array
Retrieving an Element of an Array
Related tasks
Collections
Creating an Associative Array
Two-dimensional array (runtime)
| #XPL0 | XPL0 | include c:\cxpl\codes;
char A(10); \creates a static array of 10 bytes, pointed to by "A"
char B; \declares a variable for a pointer to a dynamic array
[A(3):= 14;
B:= Reserve(10); \reserve 10 bytes and point to their starting address
B(7):= 28;
IntOut(0, A(3)+B(7)); \displays 42
] |
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 time, visit every 3rd door (door #3, #6, #9, ...), etc, until you only visit the 100th door.
Task
Answer the question: what state are the doors in after the last pass? Which are open, which are closed?
Alternate:
As noted in this page's discussion page, the only doors that remain open are those whose numbers are perfect squares.
Opening only those doors is an optimization that may also be expressed;
however, as should be obvious, this defeats the intent of comparing implementations across programming languages.
| #Onyx | Onyx | $Door dict def
1 1 100 {Door exch false put} for
$Toggle {dup Door exch get not Door up put} def
$EveryNthDoor {dup 100 {Toggle} for} def
$Run {1 1 100 {EveryNthDoor} for} def
$ShowDoor {dup `Door no. ' exch cvs cat ` is ' cat
exch Door exch get {`open.\n'}{`shut.\n'} ifelse cat
print flush} def
Run 1 1 100 {ShowDoor} for |
http://rosettacode.org/wiki/Weird_numbers | Weird numbers | In number theory, a weird number is a natural number that is abundant but not semiperfect (and therefore not perfect either).
In other words, the sum of the proper divisors of the number (divisors including 1 but not itself) is greater than the number itself (the number is abundant), but no subset of those divisors sums to the number itself (the number is not semiperfect).
For example:
12 is not a weird number.
It is abundant; its proper divisors 1, 2, 3, 4, 6 sum to 16 (which is > 12),
but it is semiperfect, e.g.: 6 + 4 + 2 == 12.
70 is a weird number.
It is abundant; its proper divisors 1, 2, 5, 7, 10, 14, 35 sum to 74 (which is > 70),
and there is no subset of proper divisors that sum to 70.
Task
Find and display, here on this page, the first 25 weird numbers.
Related tasks
Abundant, deficient and perfect number classifications
Proper divisors
See also
OEIS: A006037 weird numbers
Wikipedia: weird number
MathWorld: weird number
| #Python | Python | '''Weird numbers'''
from itertools import chain, count, islice, repeat
from functools import reduce
from math import sqrt
from time import time
# weirds :: Gen [Int]
def weirds():
'''Non-finite stream of weird numbers.
(Abundant, but not semi-perfect)
OEIS: A006037
'''
def go(n):
ds = descPropDivs(n)
d = sum(ds) - n
return [n] if 0 < d and not hasSum(d, ds) else []
return concatMap(go)(count(1))
# hasSum :: Int -> [Int] -> Bool
def hasSum(n, xs):
'''Does any subset of xs sum to n ?
(Assuming xs to be sorted in descending
order of magnitude)'''
def go(n, xs):
if xs:
h, t = xs[0], xs[1:]
if n < h: # Head too big. Forget it. Tail ?
return go(n, t)
else:
# The head IS the target ?
# Or the tail contains a sum for the
# DIFFERENCE between the head and the target ?
# Or the tail contains some OTHER sum for the target ?
return n == h or go(n - h, t) or go(n, t)
else:
return False
return go(n, xs)
# descPropDivs :: Int -> [Int]
def descPropDivs(n):
'''Descending positive divisors of n,
excluding n itself.'''
root = sqrt(n)
intRoot = int(root)
blnSqr = root == intRoot
lows = [x for x in range(1, 1 + intRoot) if 0 == n % x]
return [
n // x for x in (
lows[1:-1] if blnSqr else lows[1:]
)
] + list(reversed(lows))
# --------------------------TEST---------------------------
# main :: IO ()
def main():
'''Test'''
start = time()
n = 50
xs = take(n)(weirds())
print(
(tabulated('First ' + str(n) + ' weird numbers:\n')(
lambda i: str(1 + i)
)(str)(5)(
index(xs)
)(range(0, n)))
)
print(
'\nApprox computation time: ' +
str(int(1000 * (time() - start))) + ' ms'
)
# -------------------------GENERIC-------------------------
# chunksOf :: Int -> [a] -> [[a]]
def chunksOf(n):
'''A series of lists of length n,
subdividing the contents of xs.
Where the length of xs is not evenly divible,
the final list will be shorter than n.'''
return lambda xs: reduce(
lambda a, i: a + [xs[i:n + i]],
range(0, len(xs), n), []
) if 0 < n else []
# compose (<<<) :: (b -> c) -> (a -> b) -> a -> c
def compose(g):
'''Right to left function composition.'''
return lambda f: lambda x: g(f(x))
# concatMap :: (a -> [b]) -> [a] -> [b]
def concatMap(f):
'''A concatenated list or string over which a function f
has been mapped.
The list monad can be derived by using an (a -> [b])
function which wraps its output in a list (using an
empty list to represent computational failure).
'''
return lambda xs: chain.from_iterable(map(f, xs))
# index (!!) :: [a] -> Int -> a
def index(xs):
'''Item at given (zero-based) index.'''
return lambda n: None if 0 > n else (
xs[n] if (
hasattr(xs, "__getitem__")
) else next(islice(xs, n, None))
)
# paddedMatrix :: a -> [[a]] -> [[a]]
def paddedMatrix(v):
''''A list of rows padded to equal length
(where needed) with instances of the value v.'''
def go(rows):
return paddedRows(
len(max(rows, key=len))
)(v)(rows)
return lambda rows: go(rows) if rows else []
# paddedRows :: Int -> a -> [[a]] -[[a]]
def paddedRows(n):
'''A list of rows padded (but never truncated)
to length n with copies of value v.'''
def go(v, xs):
def pad(x):
d = n - len(x)
return (x + list(repeat(v, d))) if 0 < d else x
return list(map(pad, xs))
return lambda v: lambda xs: go(v, xs) if xs else []
# showColumns :: Int -> [String] -> String
def showColumns(n):
'''A column-wrapped string
derived from a list of rows.'''
def go(xs):
def fit(col):
w = len(max(col, key=len))
def pad(x):
return x.ljust(4 + w, ' ')
return ''.join(map(pad, col))
q, r = divmod(len(xs), n)
return unlines(map(
fit,
transpose(paddedMatrix('')(
chunksOf(q + int(bool(r)))(
xs
)
))
))
return lambda xs: go(xs)
# succ :: Enum a => a -> a
def succ(x):
'''The successor of a value. For numeric types, (1 +).'''
return 1 + x if isinstance(x, int) else (
chr(1 + ord(x))
)
# tabulated :: String -> (a -> String) ->
# (b -> String) ->
# Int ->
# (a -> b) -> [a] -> String
def tabulated(s):
'''Heading -> x display function -> fx display function ->
number of columns -> f -> value list -> tabular string.'''
def go(xShow, fxShow, intCols, f, xs):
w = max(map(compose(len)(xShow), xs))
return s + '\n' + showColumns(intCols)([
xShow(x).rjust(w, ' ') + ' -> ' + fxShow(f(x)) for x in xs
])
return lambda xShow: lambda fxShow: lambda nCols: (
lambda f: lambda xs: go(
xShow, fxShow, nCols, f, xs
)
)
# take :: Int -> [a] -> [a]
# take :: Int -> String -> String
def take(n):
'''The prefix of xs of length n,
or xs itself if n > length xs.'''
return lambda xs: (
xs[0:n]
if isinstance(xs, list)
else list(islice(xs, n))
)
# transpose :: Matrix a -> Matrix a
def transpose(m):
'''The rows and columns of the argument transposed.
(The matrix containers and rows can be lists or tuples).'''
if m:
inner = type(m[0])
z = zip(*m)
return (type(m))(
map(inner, z) if tuple != inner else z
)
else:
return m
# unlines :: [String] -> String
def unlines(xs):
'''A single string derived by the intercalation
of a list of strings with the newline character.'''
return '\n'.join(xs)
# until :: (a -> Bool) -> (a -> a) -> a -> a
def until(p):
'''The result of repeatedly applying f until p holds.
The initial seed value is x.'''
def go(f, x):
v = x
while not p(v):
v = f(v)
return v
return lambda f: lambda x: go(f, x)
# MAIN ----------------------------------------------------
if __name__ == '__main__':
main() |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Raku | Raku | # must be evenly padded with white-space$
my $text = q:to/END/;
@@@@@ @@
@ @ @ @@@
@ @ @ @@
@ @ @@@ @ @@ @ @@
@@@@@ @ @ @@ @ @ @@@@@
@ @@@@@ @ @ @@ @@
@ @ @ @ @@ @@
@ @@@ @ @@ @@@@
END
say '' for ^5;
for $text.lines -> $_ is copy {
my @chars = |｢-+ ., ;: '"｣.comb.pick(*) xx *;
s:g [' '] = @chars.shift;
print " $_ ";
s:g [('@'+)(.)] = @chars.shift ~ $0;
.say;
}
say '' for ^5; |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #Forth | Forth | include unix/socket.fs
: extract-time ( addr len type len -- time len )
dup >r
search 0= abort" that time not present!"
dup >r
begin -1 /string over 1- c@ [char] > = until \ seek back to <BR> at start of line
r> - r> + ;
s" tycho.usno.navy.mil" 80 open-socket
dup s\" GET /cgi-bin/timer.pl HTTP/1.0\n\n" rot write-socket
dup pad 4096 read-socket
s\" \r\n\r\n" search 0= abort" can't find headers!" \ skip headers
s" UTC" extract-time type cr
close-socket |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.
| #FunL | FunL | import io.Source
case Source.fromURL( 'http://tycho.usno.navy.mil/cgi-bin/timer.pl', 'UTF-8' ).getLines().find( ('Eastern' in) ) of
Some( time ) -> println( time.substring(4) )
None -> error( 'Easter time not found' ) |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.