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http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
perm
(
A
)
=
∑
σ
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \operatorname {perm} (A)=\sum _{\sigma }\prod _{i=1}^{n}M_{i,\sigma _{i}}}
In both cases the sum is over the permutations
σ
{\displaystyle \sigma }
of the permutations of 1, 2, ..., n. (A permutation's sign is 1 if there are an even number of inversions and -1 otherwise; see parity of a permutation.)
More efficient algorithms for the determinant are known: LU decomposition, see for example wp:LU decomposition#Computing the determinant. Efficient methods for calculating the permanent are not known.
Related task
Permutations by swapping
| #FreeBASIC | FreeBASIC | sub make_S( M() as double, S() as double, i as uinteger, j as uinteger )
'removes row j, column i from the matrix, stores result in S()
dim as uinteger ii, jj, size=ubound(M), ix, jx
for ii = 1 to size-1
if ii<i then ix = ii else ix = ii + 1
for jj = 1 to size-1
if jj<j then jx = jj else jx = jj + 1
S(ii, jj) = M(ix, jx)
next jj
next ii
end sub
function deperminant( M() as double, det as boolean ) as double
'calculates the determinant or the permanent of a square matrix M
'det = true for determinant, false for permanent
'assumes a square matrix
dim as uinteger size = ubound(M,1), i
dim as integer sign
dim as double S(1 to size-1, 1 to size-1)
dim as double ret = 0.0, inc
if size = 1 then return M(1,1) 'matrices of size < 3 are easy to calculate
if size = 2 and det then return M(1,1)*M(2,2) - M(1,2)*M(2,1)
if size = 2 then return M(1,1)*M(2,2) + M(1,2)*M(2,1)
for i = 1 to size
if det then sign = (-1)^(i+1) else sign = 1 'this bit is what distinguishes a determinant from a permanent
make_S( M(), S(), i, 1 )
inc = sign*M(i,1)*deperminant( S(), det ) 'recursively call on submatrices
ret += inc
next i
return ret
end function
dim as double A(1 to 2, 1 to 2) = {{1,2},{3,4}}
dim as double B(1 to 4, 1 to 4) = {_
{1,2,3,4}, {4,5,6,7}, {7,8,9,10}, {10,11,12,13} }
dim as double C(1 to 5, 1 to 5) = {_
{ 0, 1, 2, 3, 4 },_
{ 5, 6, 7, 8, 9 },_
{ 10, 11, 12, 13, 14 },_
{ 15, 16, 17, 18, 19 },_
{ 20, 21, 22, 23, 24 } }
print deperminant( A(), true ), deperminant( A(), false )
print deperminant( B(), true ), deperminant( B(), false )
print deperminant( C(), true ), deperminant( C(), false ) |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #CLU | CLU | % This will catch a divide-by-zero exception and
% return a oneof instead, with either the result or div_by_zero.
% Overflow and underflow are resignaled.
check_div = proc [T: type] (a, b: T) returns (otype)
signals (overflow, underflow)
where T has div: proctype (T,T) returns (T)
signals (zero_divide, overflow, underflow)
otype = oneof[div_by_zero: null, result: T]
return(otype$make_result(a/b))
except when zero_divide:
return(otype$make_div_by_zero(nil))
end resignal overflow, underflow
end check_div
% Try it
start_up = proc ()
pair = struct[n, d: int]
pairs: sequence[pair] := sequence[pair]$[
pair${n: 10, d: 2}, % OK
pair${n: 10, d: 0}, % divide by zero
pair${n: 20, d: 2} % another OK one to show the program doesn't stop
]
po: stream := stream$primary_output()
for p: pair in sequence[pair]$elements(pairs) do
stream$puts(po, int$unparse(p.n) || "/" || int$unparse(p.d) || " = ")
tagcase check_div[int](p.n, p.d)
tag div_by_zero: stream$putl(po, "divide by zero")
tag result (r: int): stream$putl(po, int$unparse(r))
end
end
end start_up |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #COBOL | COBOL | DIVIDE foo BY bar GIVING foobar
ON SIZE ERROR
DISPLAY "Division by zero detected!"
END-DIVIDE |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #Befunge | Befunge | ~:0\`#v_:"+"-!#v_:"-"-!#v_::"E"-\"e"-*#v_ v
v _v# < < 0<
>~:0\`#v_>::"0"-0\`\"9"-0`+!#v_:"."-!#v_::"E"-\"e"-*!#v_ v
^ $< > > $ v
>~:0\`#v_>::"0"-0\`\"9"-0`+!#v_:"."-!#v_::"E"-\"e"-*!#v_> v>
^ $< >$~:0\`#v_:"+"-#v_v
v $_v# < < :#<
>~:0\`#v_>::"0"-0\`\"9"-0`+!#v_:"."-!#v_::"E"-\"e"-*!v 0 > v
^ $< v < << ^_^#-"-"<
> "ciremuN">:#,_@ >>#$_"ciremun toN">:#,_@^ < |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #Bracmat | Bracmat | 43257349578692:/
F
260780243875083/35587980:/
S
247/30:~/#
F
80000000000:~/#
S |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as unique
process the strings from left─to─right
if unique, display a message saying such
if not unique, then:
display a message saying such
display what character is duplicated
only the 1st non─unique character need be displayed
display where "both" duplicated characters are in the string
the above messages can be part of a single message
display the hexadecimal value of the duplicated character
Use (at least) these five test values (strings):
a string of length 0 (an empty string)
a string of length 1 which is a single period (.)
a string of length 6 which contains: abcABC
a string of length 7 which contains a blank in the middle: XYZ ZYX
a string of length 36 which doesn't contain the letter "oh":
1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ
Show all output here on this page.
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.stdio;
void uniqueCharacters(string str) {
writefln("input: `%s`, length: %d", str, str.length);
foreach (i; 0 .. str.length) {
foreach (j; i + 1 .. str.length) {
if (str[i] == str[j]) {
writeln("String contains a repeated character.");
writefln("Character '%c' (hex %x) occurs at positions %d and %d.", str[i], str[i], i + 1, j + 1);
writeln;
return;
}
}
}
writeln("String contains no repeated characters.");
writeln;
}
void main() {
uniqueCharacters("");
uniqueCharacters(".");
uniqueCharacters("abcABC");
uniqueCharacters("XYZ ZYX");
uniqueCharacters("1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ");
} |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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 | import Text.Printf (printf)
import Data.Maybe (catMaybes)
import Control.Monad (guard)
input :: [String]
input = [ ""
, "The better the 4-wheel drive, the further you'll be from help when ya get stuck!"
, "headmistressship"
, "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln "
, "..1111111111111111111111111111111111111111111111111111111111111117777888"
, "I never give 'em hell, I just tell the truth, and they think it's hell. "
, " --- Harry S Truman "
, "😍😀🙌💃😍😍😍🙌"
]
collapse :: Eq a => [a] -> [a]
collapse = catMaybes . (\xs -> zipWith (\a b -> guard (a /= b) >> a) (Nothing : xs) (xs <> [Nothing])) . map Just
main :: IO ()
main =
mapM_ (\(a, b) -> printf "old: %3d «««%s»»»\nnew: %3d «««%s»»»\n\n" (length a) a (length b) b)
$ ((,) <*> collapse) <$> input |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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 | STRINGS =: <;._2]0 :0
"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln
..1111111111111111111111111111111111111111111111111111111111111117777888
I never give 'em hell, I just tell the truth, and they think it's hell.
--- Harry S Truman
)
collapse =: (#~ (1 , 2 ~:/\ ])) ::(''"_) NB. copy dissimilar neighbors
assert 1 2 3 2 3 1 2 1 -: collapse 1 2 3 2 2 2 2 3 1 1 2 2 1 NB. test
task =: ,&(<@:(;~ (_6 + #)))&('<<<' , '>>>' ,~ ]) collapse NB. assemble the output
task&> STRINGS NB. operate on the data
+-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
|+-+------+ |+-+------+ |
||0|<<<>>>| ||0|<<<>>>| |
|+-+------+ |+-+------+ |
+-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
|+--+------------------------------------------------------------------------------+|+--+----------------------------------------------------------------------------+|
||72|<<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>>|||70|<<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>>||
|+--+------------------------------------------------------------------------------+|+--+----------------------------------------------------------------------------+|
+-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
|+--+------------------------------------------------------------------------------+|+-+----------+ |
||72|<<<..1111111111111111111111111111111111111111111111111111111111111117777888>>>|||4|<<<.178>>>| |
|+--+------------------------------------------------------------------------------+|+-+----------+ |
+-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
|+--+------------------------------------------------------------------------------+|+--+---------------------------------------------------------------------------+ |
||72|<<<I never give 'em hell, I just tell the truth, and they think it's hell. >>>|||69|<<<I never give 'em hel, I just tel the truth, and they think it's hel. >>>| |
|+--+------------------------------------------------------------------------------+|+--+---------------------------------------------------------------------------+ |
+-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
|+--+------------------------------------------------------------------------------+|+--+-----------------------+ |
||72|<<< --- Harry S Truman >>>|||17|<<< - Hary S Truman >>>| |
|+--+------------------------------------------------------------------------------+|+--+-----------------------+ |
+-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
|
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as all the same character(s)
process the strings from left─to─right
if all the same character, display a message saying such
if not all the same character, then:
display a message saying such
display what character is different
only the 1st different character need be displayed
display where the different character is in the string
the above messages can be part of a single message
display the hexadecimal value of the different character
Use (at least) these seven test values (strings):
a string of length 0 (an empty string)
a string of length 3 which contains three blanks
a string of length 1 which contains: 2
a string of length 3 which contains: 333
a string of length 3 which contains: .55
a string of length 6 which contains: tttTTT
a string of length 9 with a blank in the middle: 4444 444k
Show all output here on this page.
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
| #Fortran | Fortran |
program demo_verify
implicit none
call homogeneous('')
call homogeneous('2')
call homogeneous('333')
call homogeneous('.55')
call homogeneous('tttTTT')
call homogeneous('4444 444k')
contains
subroutine homogeneous(str)
character(len=*),intent(in) :: str
character(len=:),allocatable :: ch
character(len=*),parameter :: g='(*(g0))'
integer :: where
if(len(str)>0)then;ch=str(1:1);else;ch='';endif
where=verify(str,ch)
if(where.eq.0)then
write(*,g)'STR: "',str,'" LEN: ',len(str),'. All chars are a ','"'//ch//'"'
else
write(*,g)'STR: "',str,'" LEN: ',len(str), &
& '. Multiple chars found. First difference at position ',where, &
& ' where a ','"'//str(where:where)//'"(hex:',hex(str(where:where)),') was found.'
write(*,g)repeat(' ',where+5),'^'
endif
end subroutine homogeneous
function hex(ch) result(hexstr)
character(len=1),intent(in) :: ch
character(len=:),allocatable :: hexstr
hexstr=repeat(' ',100)
write(hexstr,'(Z0)')ch
hexstr=trim(hexstr)
end function hex
end program demo_verify
|
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a round table with five individual seats. For eating each philosopher needs two forks (the resources). There are five forks on the table, one left and one right of each seat. When a philosopher cannot grab both forks it sits and waits. Eating takes random time, then the philosopher puts the forks down and leaves the dining room. After spending some random time thinking about the nature of the universe, he again becomes hungry, and the circle repeats itself.
It can be observed that a straightforward solution, when forks are implemented by semaphores, is exposed to deadlock. There exist two deadlock states when all five philosophers are sitting at the table holding one fork each. One deadlock state is when each philosopher has grabbed the fork left of him, and another is when each has the fork on his right.
There are many solutions of the problem, program at least one, and explain how the deadlock is prevented.
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | names = <|1 -> "Aristotle", 2 -> "Kant", 3 -> "Spinoza", 4 -> "Marx", 5 -> "Russell"|>;
n = Length[names];
rp := Pause[RandomReal[4]];
PrintTemporary[Dynamic[Array[forks, n]]];
Clear[forks]; forks[_] := Null;
With[{nf = n},
ParallelDo[
With[{i1 = i, i2 = Mod[i + 1, nf, 1]},
Do[Print[names[i], " thinking"]; rp; Print[names[i], " hungry"];
CriticalSection[{forks[i1], forks[i2]},
Print[names[i], " eating"]; rp],
{2}]],
{i, nf}]]; |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #MAD | MAD | R DISCORDIAN DATE CALCULATION
R
R PUNCH CARD SHOULD CONTAIN -
R MM/DD/YYYY
R IN GREGORIAN CALENDAR
NORMAL MODE IS INTEGER
VECTOR VALUES MLENGT =
0 0,0,31,59,90,120,151,181,212,243,273,304,334
VECTOR VALUES TIBS =
0 $31HSAINT TIBS DAY IN THE Y.O.L.D. ,I4*$
VECTOR VALUES DISDAT =
0 $C,6H, DAY ,I2,S1,3HOF ,C,S1,16HIN THE Y.O.L.D. ,I4*$
VECTOR VALUES DISDAY = $SWEETMORN$, $BOOMTIME$,
0 $PUNGENDAY$, $PRICKLE-PRICKLE$, $SETTING ORANGE$
VECTOR VALUES DISSSN = $CHAOS$, $DISCORD$,
0 $CONFUSION$, $BUREAUCRACY$, $THE AFTERMATH$
VECTOR VALUES CLDAY = $10HCELEBRATE ,C,3HDAY*$
VECTOR VALUES CLFLUX = $10HCELEBRATE ,C,4HFLUX*$
VECTOR VALUES HOLY5 = $MUNG$,$MOJO$,$SYA$,$ZARA$,$MALA$
VECTOR VALUES HOLY50 = $CHAO$,$DISCO$,$CONFU$,$BURE$,$AF$
READ FORMAT GREG,GMONTH,GDAY,GYEAR
VECTOR VALUES GREG = $2(I2,1H/),I4*$
WHENEVER GMONTH.E.2 .AND. GDAY.E.29
PRINT FORMAT TIBS, GYEAR + 1166
OTHERWISE
YRDAY = MLENGT(GMONTH)+GDAY
SEASON = YRDAY/73
DAY = YRDAY-SEASON*73
WKDAY = (YRDAY-1)-(YRDAY-1)/5*5
PRINT FORMAT DISDAT, DISDAY(WKDAY), DAY,
0 DISSSN(SEASON), GYEAR + 1166
WHENEVER DAY.E.5
PRINT FORMAT CLDAY, HOLY5(SEASON)
OR WHENEVER DAY.E.50
PRINT FORMAT CLFLUX, HOLY50(SEASON)
END OF CONDITIONAL
END OF CONDITIONAL
END OF PROGRAM |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path problem for a graph with non-negative edge path costs, producing a shortest path tree.
This algorithm is often used in routing and as a subroutine in other graph algorithms.
For a given source vertex (node) in the graph, the algorithm finds the path with lowest cost (i.e. the shortest path) between that vertex and every other vertex.
For instance
If the vertices of the graph represent cities and edge path costs represent driving distances between pairs of cities connected by a direct road, Dijkstra's algorithm can be used to find the shortest route between one city and all other cities.
As a result, the shortest path first is widely used in network routing protocols, most notably:
IS-IS (Intermediate System to Intermediate System) and
OSPF (Open Shortest Path First).
Important note
The inputs to Dijkstra's algorithm are a directed and weighted graph consisting of 2 or more nodes, generally represented by:
an adjacency matrix or list, and
a start node.
A destination node is not specified.
The output is a set of edges depicting the shortest path to each destination node.
An example, starting with
a──►b, cost=7, lastNode=a
a──►c, cost=9, lastNode=a
a──►d, cost=NA, lastNode=a
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►b so a──►b is added to the output.
There is a connection from b──►d so the input is updated to:
a──►c, cost=9, lastNode=a
a──►d, cost=22, lastNode=b
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►c so a──►c is added to the output.
Paths to d and f are cheaper via c so the input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
a──►f, cost=11, lastNode=c
The lowest cost is a──►f so c──►f is added to the output.
The input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
The lowest cost is a──►d so c──►d is added to the output.
There is a connection from d──►e so the input is updated to:
a──►e, cost=26, lastNode=d
Which just leaves adding d──►e to the output.
The output should now be:
[ d──►e
c──►d
c──►f
a──►c
a──►b ]
Task
Implement a version of Dijkstra's algorithm that outputs a set of edges depicting the shortest path to each reachable node from an origin.
Run your program with the following directed graph starting at node a.
Write a program which interprets the output from the above and use it to output the shortest path from node a to nodes e and f.
Vertices
Number
Name
1
a
2
b
3
c
4
d
5
e
6
f
Edges
Start
End
Cost
a
b
7
a
c
9
a
f
14
b
c
10
b
d
15
c
d
11
c
f
2
d
e
6
e
f
9
You can use numbers or names to identify vertices in your program.
See also
Dijkstra's Algorithm vs. A* Search vs. Concurrent Dijkstra's Algorithm (youtube)
| #Maxima | Maxima | load(graphs)$
g: create_graph([[1, "a"], [2, "b"], [3, "c"], [4, "d"], [5, "e"], [6, "f"]],
[[[1, 2], 7],
[[1, 3], 9],
[[1, 6], 14],
[[2, 3], 10],
[[2, 4], 15],
[[3, 4], 11],
[[3, 6], 2],
[[4, 5], 6],
[[5, 6], 9]], directed)$
shortest_weighted_path(1, 5, g);
/* [26, [1, 3, 4, 5]] */ |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displaystyle X}
has only one digit.
The additive persistence is the number of summations required to obtain the single digit.
The task is to calculate the additive persistence and the digital root of a number, e.g.:
627615
{\displaystyle 627615}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
39390
{\displaystyle 39390}
has additive persistence
2
{\displaystyle 2}
and digital root of
6
{\displaystyle 6}
;
588225
{\displaystyle 588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
3
{\displaystyle 3}
;
393900588225
{\displaystyle 393900588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
The digital root may be calculated in bases other than 10.
See
Casting out nines for this wiki's use of this procedure.
Digital root/Multiplicative digital root
Sum digits of an integer
Digital root sequence on OEIS
Additive persistence sequence on OEIS
Iterated digits squaring
| #Groovy | Groovy | class DigitalRoot {
static int[] calcDigitalRoot(String number, int base) {
BigInteger bi = new BigInteger(number, base)
int additivePersistence = 0
if (bi.signum() < 0) {
bi = bi.negate()
}
BigInteger biBase = BigInteger.valueOf(base)
while (bi >= biBase) {
number = bi.toString(base)
bi = BigInteger.ZERO
for (int i = 0; i < number.length(); i++) {
bi = bi.add(new BigInteger(number.substring(i, i + 1), base))
}
additivePersistence++
}
return [additivePersistence, bi.intValue()]
}
static void main(String[] args) {
for (String arg : [627615, 39390, 588225, 393900588225]) {
int[] results = calcDigitalRoot(arg, 10)
println("$arg has additive persistence ${results[0]} and digital root of ${results[1]}")
}
}
} |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
{\displaystyle 0}
.
While
m
{\displaystyle m}
has more than one digit:
Find a replacement
m
{\displaystyle m}
as the multiplication of the digits of the current value of
m
{\displaystyle m}
.
Increment
i
{\displaystyle i}
.
Return
i
{\displaystyle i}
(= MP) and
m
{\displaystyle m}
(= MDR)
Task
Tabulate the MP and MDR of the numbers 123321, 7739, 893, 899998
Tabulate MDR versus the first five numbers having that MDR, something like:
MDR: [n0..n4]
=== ========
0: [0, 10, 20, 25, 30]
1: [1, 11, 111, 1111, 11111]
2: [2, 12, 21, 26, 34]
3: [3, 13, 31, 113, 131]
4: [4, 14, 22, 27, 39]
5: [5, 15, 35, 51, 53]
6: [6, 16, 23, 28, 32]
7: [7, 17, 71, 117, 171]
8: [8, 18, 24, 29, 36]
9: [9, 19, 33, 91, 119]
Show all output on this page.
Similar
The Product of decimal digits of n page was redirected here, and had the following description
Find the product of the decimal digits of a positive integer n, where n <= 100
The three existing entries for Phix, REXX, and Ring have been moved here, under ===Similar=== headings, feel free to match or ignore them.
References
Multiplicative Digital Root on Wolfram Mathworld.
Multiplicative digital root on The On-Line Encyclopedia of Integer Sequences.
What's special about 277777788888899? - Numberphile video
| #Ring | Ring |
# Project : Digital root/Multiplicative digital root
load "stdlib.ring"
root = newlist(10, 5)
for r = 1 to 10
for x = 1 to 5
root[r][x] = 0
next
next
root2 = list(10)
for y = 1 to 10
root2[y] = 0
next
see "Number MDR MP" + nl
num = [123321, 7739, 893, 899998]
digroot(num)
see nl
num = 0:12000
digroot(num)
see "First five numbers with MDR in first column:" + nl
for n1 = 1 to 10
see "" + (n1-1) + " => "
for n2 = 1 to 5
see "" + root[n1][n2] + " "
next
see nl
next
func digroot(num)
for n = 1 to len(num)
sum = 0
numold = num[n]
while true
pro = 1
strnum = string(numold)
for nr = 1 to len(strnum)
pro = pro * number(strnum[nr])
next
sum = sum + 1
numold = pro
numn = string(num[n])
sp = 6 - len(string(num[n]))
if sp > 0
for p = 1 to sp + 2
numn = " " + numn
next
ok
if len(string(numold)) = 1 and len(num) < 5
see "" + numn + " " + numold + " " + sum + nl
exit
ok
if len(string(numold)) = 1 and len(num) > 4
root2[numold+1] = root2[numold+1] + 1
if root2[numold+1] < 6
root[numold+1][root2[numold+1]] = num[n]
ok
exit
ok
end
next
|
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
{\displaystyle 0}
.
While
m
{\displaystyle m}
has more than one digit:
Find a replacement
m
{\displaystyle m}
as the multiplication of the digits of the current value of
m
{\displaystyle m}
.
Increment
i
{\displaystyle i}
.
Return
i
{\displaystyle i}
(= MP) and
m
{\displaystyle m}
(= MDR)
Task
Tabulate the MP and MDR of the numbers 123321, 7739, 893, 899998
Tabulate MDR versus the first five numbers having that MDR, something like:
MDR: [n0..n4]
=== ========
0: [0, 10, 20, 25, 30]
1: [1, 11, 111, 1111, 11111]
2: [2, 12, 21, 26, 34]
3: [3, 13, 31, 113, 131]
4: [4, 14, 22, 27, 39]
5: [5, 15, 35, 51, 53]
6: [6, 16, 23, 28, 32]
7: [7, 17, 71, 117, 171]
8: [8, 18, 24, 29, 36]
9: [9, 19, 33, 91, 119]
Show all output on this page.
Similar
The Product of decimal digits of n page was redirected here, and had the following description
Find the product of the decimal digits of a positive integer n, where n <= 100
The three existing entries for Phix, REXX, and Ring have been moved here, under ===Similar=== headings, feel free to match or ignore them.
References
Multiplicative Digital Root on Wolfram Mathworld.
Multiplicative digital root on The On-Line Encyclopedia of Integer Sequences.
What's special about 277777788888899? - Numberphile video
| #Ruby | Ruby | def mdroot(n)
mdr, persist = n, 0
until mdr < 10 do
mdr = mdr.digits.inject(:*)
persist += 1
end
[mdr, persist]
end
puts "Number: MDR MP", "====== === =="
[123321, 7739, 893, 899998].each{|n| puts "%6d: %d %2d" % [n, *mdroot(n)]}
counter = Hash.new{|h,k| h[k]=[]}
0.step do |i|
counter[mdroot(i).first] << i
break if counter.values.all?{|v| v.size >= 5 }
end
puts "", "MDR: [n0..n4]", "=== ========"
10.times{|i| puts "%3d: %p" % [i, counter[i].first(5)]} |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of expression are valued.
Examples may be be split into "setup", "problem statement", and "output" sections where the ease and naturalness of stating the problem and getting an answer, as well as the ease and flexibility of modifying the problem are the primary concerns.
Example output should be shown here, as well as any comments on the examples flexibility.
The problem
Baker, Cooper, Fletcher, Miller, and Smith live on different floors of an apartment house that contains only five floors.
Baker does not live on the top floor.
Cooper does not live on the bottom floor.
Fletcher does not live on either the top or the bottom floor.
Miller lives on a higher floor than does Cooper.
Smith does not live on a floor adjacent to Fletcher's.
Fletcher does not live on a floor adjacent to Cooper's.
Where does everyone live?
| #Nim | Nim | import algorithm
type
Person {.pure.} = enum Baker, Cooper, Fletcher, Miller, Smith
Floor = range[1..5]
var floors: array[Person, Floor] = [Floor 1, 2, 3, 4, 5]
while true:
if floors[Baker] != 5 and
floors[Cooper] != 1 and
floors[Fletcher] notin [1, 5] and
floors[Miller] > floors[Cooper] and
abs(floors[Smith] - floors[Fletcher]) != 1 and
abs(floors[Fletcher] - floors[Cooper]) != 1:
for person, floor in floors:
echo person, " lives on floor ", floor
break
if not floors.nextPermutation():
echo "No solution found."
break |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot product of two vectors directly:
each vector must be the same length
multiply corresponding terms from each vector
sum the products (to produce the answer)
Related task
Vector products
| #Groovy | Groovy | def dotProduct = { x, y ->
assert x && y && x.size() == y.size()
[x, y].transpose().collect{ xx, yy -> xx * yy }.sum()
} |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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 |
dlb
}.~ (=&' ' (i.) 0:)
dtb
#~ ([: +./\. ' '&~:)
deb
#~ ((+.) (1: |. (> </\)))@(' '&~:)
|
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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 |
// Title: Determine if a string is squeezable
public class StringSqueezable {
public static void main(String[] args) {
String[] testStrings = new String[] {
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I never give 'em hell, I just tell the truth, and they think it's hell. ",
" --- Harry S Truman ",
"122333444455555666666777777788888888999999999",
"The better the 4-wheel drive, the further you'll be from help when ya get stuck!",
"headmistressship"};
String[] testChar = new String[] {
" ",
"-",
"7",
".",
" -r",
"5",
"e",
"s"};
for ( int testNum = 0 ; testNum < testStrings.length ; testNum++ ) {
String s = testStrings[testNum];
for ( char c : testChar[testNum].toCharArray() ) {
String result = squeeze(s, c);
System.out.printf("use: '%c'%nold: %2d <<<%s>>>%nnew: %2d <<<%s>>>%n%n", c, s.length(), s, result.length(), result);
}
}
}
private static String squeeze(String in, char include) {
StringBuilder sb = new StringBuilder();
for ( int i = 0 ; i < in.length() ; i++ ) {
if ( i == 0 || in.charAt(i-1) != in.charAt(i) || (in.charAt(i-1) == in.charAt(i) && in.charAt(i) != include)) {
sb.append(in.charAt(i));
}
}
return sb.toString();
}
}
|
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to improve performance. In each case the experiment begins with the funnel positioned directly over the target.
Rule 1: The funnel remains directly above the target.
Rule 2: Adjust the funnel position by shifting the target to compensate after each drop. E.g. If the last drop missed 1 cm east, move the funnel 1 cm to the west of its current position.
Rule 3: As rule 2, but first move the funnel back over the target, before making the adjustment. E.g. If the funnel is 2 cm north, and the marble lands 3 cm north, move the funnel 3 cm south of the target.
Rule 4: The funnel is moved directly over the last place a marble landed.
Apply the four rules to the set of 50 pseudorandom displacements provided (e.g in the Racket solution) for the dxs and dys. Output: calculate the mean and standard-deviations of the resulting x and y values for each rule.
Note that rules 2, 3, and 4 give successively worse results. Trying to deterministically compensate for a random process is counter-productive, but -- according to Deming -- quite a popular pastime: see the Further Information, below for examples.
Stretch goal 1: Generate fresh pseudorandom data. The radial displacement of the drop from the funnel position is given by a Gaussian distribution (standard deviation is 1.0) and the angle of displacement is uniformly distributed.
Stretch goal 2: Show scatter plots of all four results.
Further information
Further explanation and interpretation
Video demonstration of the funnel experiment at the Mayo Clinic. | #Java | Java | import static java.lang.Math.*;
import java.util.Arrays;
import java.util.function.BiFunction;
public class DemingsFunnel {
public static void main(String[] args) {
double[] dxs = {
-0.533, 0.270, 0.859, -0.043, -0.205, -0.127, -0.071, 0.275,
1.251, -0.231, -0.401, 0.269, 0.491, 0.951, 1.150, 0.001,
-0.382, 0.161, 0.915, 2.080, -2.337, 0.034, -0.126, 0.014,
0.709, 0.129, -1.093, -0.483, -1.193, 0.020, -0.051, 0.047,
-0.095, 0.695, 0.340, -0.182, 0.287, 0.213, -0.423, -0.021,
-0.134, 1.798, 0.021, -1.099, -0.361, 1.636, -1.134, 1.315,
0.201, 0.034, 0.097, -0.170, 0.054, -0.553, -0.024, -0.181,
-0.700, -0.361, -0.789, 0.279, -0.174, -0.009, -0.323, -0.658,
0.348, -0.528, 0.881, 0.021, -0.853, 0.157, 0.648, 1.774,
-1.043, 0.051, 0.021, 0.247, -0.310, 0.171, 0.000, 0.106,
0.024, -0.386, 0.962, 0.765, -0.125, -0.289, 0.521, 0.017,
0.281, -0.749, -0.149, -2.436, -0.909, 0.394, -0.113, -0.598,
0.443, -0.521, -0.799, 0.087};
double[] dys = {
0.136, 0.717, 0.459, -0.225, 1.392, 0.385, 0.121, -0.395,
0.490, -0.682, -0.065, 0.242, -0.288, 0.658, 0.459, 0.000,
0.426, 0.205, -0.765, -2.188, -0.742, -0.010, 0.089, 0.208,
0.585, 0.633, -0.444, -0.351, -1.087, 0.199, 0.701, 0.096,
-0.025, -0.868, 1.051, 0.157, 0.216, 0.162, 0.249, -0.007,
0.009, 0.508, -0.790, 0.723, 0.881, -0.508, 0.393, -0.226,
0.710, 0.038, -0.217, 0.831, 0.480, 0.407, 0.447, -0.295,
1.126, 0.380, 0.549, -0.445, -0.046, 0.428, -0.074, 0.217,
-0.822, 0.491, 1.347, -0.141, 1.230, -0.044, 0.079, 0.219,
0.698, 0.275, 0.056, 0.031, 0.421, 0.064, 0.721, 0.104,
-0.729, 0.650, -1.103, 0.154, -1.720, 0.051, -0.385, 0.477,
1.537, -0.901, 0.939, -0.411, 0.341, -0.411, 0.106, 0.224,
-0.947, -1.424, -0.542, -1.032};
experiment("Rule 1:", dxs, dys, (z, dz) -> 0.0);
experiment("Rule 2:", dxs, dys, (z, dz) -> -dz);
experiment("Rule 3:", dxs, dys, (z, dz) -> -(z + dz));
experiment("Rule 4:", dxs, dys, (z, dz) -> z + dz);
}
static void experiment(String label, double[] dxs, double[] dys,
BiFunction<Double, Double, Double> rule) {
double[] resx = funnel(dxs, rule);
double[] resy = funnel(dys, rule);
System.out.println(label);
System.out.printf("Mean x, y: %.4f, %.4f%n", mean(resx), mean(resy));
System.out.printf("Std dev x, y: %.4f, %.4f%n", stdDev(resx), stdDev(resy));
System.out.println();
}
static double[] funnel(double[] input, BiFunction<Double, Double, Double> rule) {
double x = 0;
double[] result = new double[input.length];
for (int i = 0; i < input.length; i++) {
double rx = x + input[i];
x = rule.apply(x, input[i]);
result[i] = rx;
}
return result;
}
static double mean(double[] xs) {
return Arrays.stream(xs).sum() / xs.length;
}
static double stdDev(double[] xs) {
double m = mean(xs);
return sqrt(Arrays.stream(xs).map(x -> pow((x - m), 2)).sum() / xs.length);
}
} |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and must add up to 12.
The Chief of the Police doesn't like odd numbers and wants to have an even number for his department.
Task
Write a computer program which outputs all valid combinations.
Possible output (for the 1st and 14th solutions):
--police-- --sanitation-- --fire--
2 3 7
6 5 1
| #ALGOL_68 | ALGOL 68 | BEGIN
# show possible department number allocations for police, sanitation and fire departments #
# the police department number must be even, all department numbers in the range 1 .. 7 #
# the sum of the department numbers must be 12 #
INT max department number = 7;
INT department sum = 12;
print( ( "police sanitation fire", newline ) );
FOR police FROM 2 BY 2 TO max department number DO
FOR sanitation TO max department number DO
IF sanitation /= police THEN
INT fire = ( department sum - police ) - sanitation;
IF fire > 0 AND fire <= max department number
AND fire /= sanitation
AND fire /= police
THEN
print( ( whole( police, -6 )
, whole( sanitation, -11 )
, whole( fire, -5 )
, newline
)
)
FI
FI
OD
OD
END |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects responsibilities:
Delegator:
Keep an optional delegate instance.
Implement "operation" method, returning the delegate "thing" if the delegate respond to "thing", or the string "default implementation".
Delegate:
Implement "thing" and return the string "delegate implementation"
Show how objects are created and used. First, without a delegate, then with a delegate that does not implement "thing", and last with a delegate that implements "thing".
| #C.2B.2B | C++ |
#include <tr1/memory>
#include <string>
#include <iostream>
#include <tr1/functional>
using namespace std;
using namespace std::tr1;
using std::tr1::function;
// interface for all delegates
class IDelegate
{
public:
virtual ~IDelegate() {}
};
//interface for delegates supporting thing
class IThing
{
public:
virtual ~IThing() {}
virtual std::string Thing() = 0;
};
// Does not handle Thing
class DelegateA : virtual public IDelegate
{
};
// Handles Thing
class DelegateB : public IThing, public IDelegate
{
std::string Thing()
{
return "delegate implementation";
}
};
class Delegator
{
public:
std::string Operation()
{
if(Delegate) //have delegate
if (IThing * pThing = dynamic_cast<IThing*>(Delegate.get()))
//delegate provides IThing interface
return pThing->Thing();
return "default implementation";
}
shared_ptr<IDelegate> Delegate;
};
int main()
{
shared_ptr<DelegateA> delegateA(new DelegateA());
shared_ptr<DelegateB> delegateB(new DelegateB());
Delegator delegator;
// No delegate
std::cout << delegator.Operation() << std::endl;
// Delegate doesn't handle "Thing"
delegator.Delegate = delegateA;
std::cout << delegator.Operation() << std::endl;
// Delegate handles "Thing"
delegator.Delegate = delegateB;
std::cout << delegator.Operation() << std::endl;
/*
Prints:
default implementation
default implementation
delegate implementation
*/
}
|
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)
(0,0),(5,0),(2.5,5) and (0,4),(2.5,-1),(5,4)
(0,0),(1,1),(0,2) and (2,1),(3,0),(3,2)
(0,0),(1,1),(0,2) and (2,1),(3,-2),(3,4)
Optionally, see what the result is when only a single corner is in contact (there is no definitive correct answer):
(0,0),(1,0),(0,1) and (1,0),(2,0),(1,1)
| #Go | Go | package main
import "fmt"
type point struct {
x, y float64
}
func (p point) String() string {
return fmt.Sprintf("(%.1f, %.1f)", p.x, p.y)
}
type triangle struct {
p1, p2, p3 point
}
func (t *triangle) String() string {
return fmt.Sprintf("Triangle %s, %s, %s", t.p1, t.p2, t.p3)
}
func (t *triangle) det2D() float64 {
return t.p1.x * (t.p2.y - t.p3.y) +
t.p2.x * (t.p3.y - t.p1.y) +
t.p3.x * (t.p1.y - t.p2.y)
}
func (t *triangle) checkTriWinding(allowReversed bool) {
detTri := t.det2D()
if detTri < 0.0 {
if allowReversed {
a := t.p3
t.p3 = t.p2
t.p2 = a
} else {
panic("Triangle has wrong winding direction.")
}
}
}
func boundaryCollideChk(t *triangle, eps float64) bool {
return t.det2D() < eps
}
func boundaryDoesntCollideChk(t *triangle, eps float64) bool {
return t.det2D() <= eps
}
func triTri2D(t1, t2 *triangle, eps float64, allowReversed, onBoundary bool) bool {
// Triangles must be expressed anti-clockwise.
t1.checkTriWinding(allowReversed)
t2.checkTriWinding(allowReversed)
// 'onBoundary' determines whether points on boundary are considered as colliding or not.
var chkEdge func (*triangle, float64) bool
if onBoundary {
chkEdge = boundaryCollideChk
} else {
chkEdge = boundaryDoesntCollideChk
}
lp1 := [3]point{t1.p1, t1.p2, t1.p3}
lp2 := [3]point{t2.p1, t2.p2, t2.p3}
// for each edge E of t1
for i := 0; i < 3; i++ {
j := (i + 1) % 3
// Check all points of t2 lay on the external side of edge E.
// If they do, the triangles do not overlap.
tri1 := &triangle{lp1[i], lp1[j], lp2[0]}
tri2 := &triangle{lp1[i], lp1[j], lp2[1]}
tri3 := &triangle{lp1[i], lp1[j], lp2[2]}
if chkEdge(tri1, eps) && chkEdge(tri2, eps) && chkEdge(tri3, eps) {
return false
}
}
// for each edge E of t2
for i := 0; i < 3; i++ {
j := (i + 1) % 3
// Check all points of t1 lay on the external side of edge E.
// If they do, the triangles do not overlap.
tri1 := &triangle{lp2[i], lp2[j], lp1[0]}
tri2 := &triangle{lp2[i], lp2[j], lp1[1]}
tri3 := &triangle{lp2[i], lp2[j], lp1[2]}
if chkEdge(tri1, eps) && chkEdge(tri2, eps) && chkEdge(tri3, eps) {
return false
}
}
// The triangles overlap.
return true
}
func iff(cond bool, s1, s2 string) string {
if cond {
return s1
}
return s2
}
func main() {
t1 := &triangle{point{0.0, 0.0}, point{5.0, 0.0}, point{0.0, 5.0}}
t2 := &triangle{point{0.0, 0.0}, point{5.0, 0.0}, point{0.0, 6.0}}
fmt.Printf("%s and\n%s\n", t1, t2)
overlapping := triTri2D(t1, t2, 0.0, false, true)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
// Need to allow reversed for this pair to avoid panic.
t1 = &triangle{point{0.0, 0.0}, point{0.0, 5.0}, point{5.0, 0.0}}
t2 = t1
fmt.Printf("\n%s and\n%s\n", t1, t2)
overlapping = triTri2D(t1, t2, 0.0, true, true)
fmt.Println(iff(overlapping, "overlap (reversed)", "do not overlap"))
t1 = &triangle{point{0.0, 0.0}, point{5.0, 0.0}, point{0.0, 5.0}}
t2 = &triangle{point{-10.0, 0.0}, point{-5.0, 0.0}, point{-1.0, 6.0}}
fmt.Printf("\n%s and\n%s\n", t1, t2)
overlapping = triTri2D(t1, t2, 0.0, false, true)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
t1.p3 = point{2.5, 5.0}
t2 = &triangle{point{0.0, 4.0}, point{2.5, -1.0}, point{5.0, 4.0}}
fmt.Printf("\n%s and\n%s\n", t1, t2)
overlapping = triTri2D(t1, t2, 0.0, false, true)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
t1 = &triangle{point{0.0, 0.0}, point{1.0, 1.0}, point{0.0, 2.0}}
t2 = &triangle{point{2.0, 1.0}, point{3.0, 0.0}, point{3.0, 2.0}}
fmt.Printf("\n%s and\n%s\n", t1, t2)
overlapping = triTri2D(t1, t2, 0.0, false, true)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
t2 = &triangle{point{2.0, 1.0}, point{3.0, -2.0}, point{3.0, 4.0}}
fmt.Printf("\n%s and\n%s\n", t1, t2)
overlapping = triTri2D(t1, t2, 0.0, false, true)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
t1 = &triangle{point{0.0, 0.0}, point{1.0, 0.0}, point{0.0, 1.0}}
t2 = &triangle{point{1.0, 0.0}, point{2.0, 0.0}, point{1.0, 1.1}}
fmt.Printf("\n%s and\n%s\n", t1, t2)
println("which have only a single corner in contact, if boundary points collide")
overlapping = triTri2D(t1, t2, 0.0, false, true)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
fmt.Printf("\n%s and\n%s\n", t1, t2)
fmt.Println("which have only a single corner in contact, if boundary points do not collide")
overlapping = triTri2D(t1, t2, 0.0, false, false)
fmt.Println(iff(overlapping, "overlap", "do not overlap"))
} |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #AWK | AWK | system("rm input.txt")
system("rm /input.txt")
system("rm -rf docs")
system("rm -rf /docs") |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Axe | Axe | DelVar "appvINPUT" |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
perm
(
A
)
=
∑
σ
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \operatorname {perm} (A)=\sum _{\sigma }\prod _{i=1}^{n}M_{i,\sigma _{i}}}
In both cases the sum is over the permutations
σ
{\displaystyle \sigma }
of the permutations of 1, 2, ..., n. (A permutation's sign is 1 if there are an even number of inversions and -1 otherwise; see parity of a permutation.)
More efficient algorithms for the determinant are known: LU decomposition, see for example wp:LU decomposition#Computing the determinant. Efficient methods for calculating the permanent are not known.
Related task
Permutations by swapping
| #FunL | FunL | def sgn( p ) = product( (if s(0) < s(1) xor i(0) < i(1) then -1 else 1) | (s, i) <- p.combinations(2).zip( (0:p.length()).combinations(2) ) )
def perm( m ) = sum( product(m(i, sigma(i)) | i <- 0:m.length()) | sigma <- (0:m.length()).permutations() )
def det( m ) = sum( sgn(sigma)*product(m(i, sigma(i)) | i <- 0:m.length()) | sigma <- (0:m.length()).permutations() ) |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
perm
(
A
)
=
∑
σ
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \operatorname {perm} (A)=\sum _{\sigma }\prod _{i=1}^{n}M_{i,\sigma _{i}}}
In both cases the sum is over the permutations
σ
{\displaystyle \sigma }
of the permutations of 1, 2, ..., n. (A permutation's sign is 1 if there are an even number of inversions and -1 otherwise; see parity of a permutation.)
More efficient algorithms for the determinant are known: LU decomposition, see for example wp:LU decomposition#Computing the determinant. Efficient methods for calculating the permanent are not known.
Related task
Permutations by swapping
| #GLSL | GLSL |
mat4 m1 = mat3(1, 2, 3, 4,
5, 6, 7, 8
9,10,11,12,
13,14,15,16);
float d = det(m1);
|
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Common_Lisp | Common Lisp | (handler-case (/ x y)
(division-by-zero () (format t "division by zero caught!~%"))) |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #D | D | import std.stdio, std.string, std.math, std.traits;
string divCheck(T)(in T numer, in T denom)
if (isIntegral!T || isFloatingPoint!T) {
Unqual!(typeof(numer / denom)) result;
string msg;
static if (isIntegral!T) {
try {
result = numer / denom;
} catch(Error e) {
msg = "| " ~ e.msg ~ " (by Error)";
result = T.max;
}
} else { // Floating Point Type.
result = numer / denom;
if (numer.isNormal && result.isInfinity) {
msg = "| Division by Zero";
} else if (result != 0 && !result.isNormal) {
if (numer.isNaN)
msg = "| NaN numerator";
else if (denom.isNaN)
msg = "| NaN denominator";
else if (numer.isInfinity)
msg = "| Inf numerator";
else
msg = "| NaN (Zero Division by Zero)";
}
}
return format("%5s %s", format("%1.1g", real(result)), msg);
}
void main() {
writeln("Division with check:");
writefln("int 1/ 0: %s", divCheck(1, 0));
writefln("ubyte 1/ 0: %s", divCheck(ubyte(1), ubyte(0)));
writefln("real 1/ 0: %s", divCheck(1.0L, 0.0L));
writefln("real -1/ 0: %s", divCheck(-1.0L, 0.0L));
writefln("real 0/ 0: %s", divCheck(0.0L, 0.0L));
writeln;
writefln("real -4/-2: %s", divCheck(-4.0L,-2.0L));
writefln("real 2/-inf: %s", divCheck(2.0L, -real.infinity));
writeln;
writefln("real -inf/-2: %s", divCheck(-real.infinity, -2.0L));
writefln("real +inf/-2: %s", divCheck(real.infinity, -2.0L));
writefln("real nan/-2: %s", divCheck(real.nan, -2.0L));
writefln("real -2/ nan: %s", divCheck(-2.0L, real.nan));
writefln("real nan/ 0: %s", divCheck(real.nan, 0.0L));
writefln("real inf/ inf: %s",
divCheck(real.infinity, real.infinity));
writefln("real nan/ nan: %s", divCheck(real.nan, real.nan));
} |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #Burlesque | Burlesque |
ps^^-]to{"Int""Double"}\/~[\/L[1==?*
|
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #C | C | #include <ctype.h>
#include <stdlib.h>
int isNumeric (const char * s)
{
if (s == NULL || *s == '\0' || isspace(*s))
return 0;
char * p;
strtod (s, &p);
return *p == '\0';
} |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as unique
process the strings from left─to─right
if unique, display a message saying such
if not unique, then:
display a message saying such
display what character is duplicated
only the 1st non─unique character need be displayed
display where "both" duplicated characters are in the string
the above messages can be part of a single message
display the hexadecimal value of the duplicated character
Use (at least) these five test values (strings):
a string of length 0 (an empty string)
a string of length 1 which is a single period (.)
a string of length 6 which contains: abcABC
a string of length 7 which contains a blank in the middle: XYZ ZYX
a string of length 36 which doesn't contain the letter "oh":
1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ
Show all output here on this page.
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 Determine_if_a_string_has_all_unique_characters;
{$APPTYPE CONSOLE}
uses
System.SysUtils;
procedure string_has_repeated_character(str: string);
var
len, i, j: Integer;
begin
len := length(str);
Writeln('input: \', str, '\, length: ', len);
for i := 1 to len - 1 do
begin
for j := i + 1 to len do
begin
if str[i] = str[j] then
begin
Writeln('String contains a repeated character.');
Writeln('Character "', str[i], '" (hex ', ord(str[i]).ToHexString,
') occurs at positions ', i + 1, ' and ', j + 1, '.'#10);
Exit;
end;
end;
end;
Writeln('String contains no repeated characters.' + sLineBreak);
end;
begin
string_has_repeated_character('');
string_has_repeated_character('.');
string_has_repeated_character('abcABC');
string_has_repeated_character('XYZ ZYX');
string_has_repeated_character('1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ');
readln;
end. |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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 |
// Title: Determine if a string is collapsible
public class StringCollapsible {
public static void main(String[] args) {
for ( String s : new String[] {
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I never give 'em hell, I just tell the truth, and they think it's hell. ",
" --- Harry S Truman ",
"122333444455555666666777777788888888999999999",
"The better the 4-wheel drive, the further you'll be from help when ya get stuck!",
"headmistressship"}) {
String result = collapse(s);
System.out.printf("old: %2d <<<%s>>>%nnew: %2d <<<%s>>>%n%n", s.length(), s, result.length(), result);
}
}
private static String collapse(String in) {
StringBuilder sb = new StringBuilder();
for ( int i = 0 ; i < in.length() ; i++ ) {
if ( i == 0 || in.charAt(i-1) != in.charAt(i) ) {
sb.append(in.charAt(i));
}
}
return sb.toString();
}
}
|
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as all the same character(s)
process the strings from left─to─right
if all the same character, display a message saying such
if not all the same character, then:
display a message saying such
display what character is different
only the 1st different character need be displayed
display where the different character is in the string
the above messages can be part of a single message
display the hexadecimal value of the different character
Use (at least) these seven test values (strings):
a string of length 0 (an empty string)
a string of length 3 which contains three blanks
a string of length 1 which contains: 2
a string of length 3 which contains: 333
a string of length 3 which contains: .55
a string of length 6 which contains: tttTTT
a string of length 9 with a blank in the middle: 4444 444k
Show all output here on this page.
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
| #FreeBASIC | FreeBASIC | dim as string s, nxt
input "Enter string: ", s
if len(s)<2 then 'A string with one or zero characters passes by default
print "All characters are the same."
end
end if
dim as ubyte i
for i = 1 to len(s)-1
nxt = mid(s, i+1, 1)
if mid(s, i, 1)<>nxt then 'if any character differs from the previous one
print "First non-matching char is "+nxt
print "It occurs at position "+str(i+1)
print "Its hex value is "+hex(asc(nxt))
end
end if
next i
'otherwise, success!
print "All characters are the same." |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as all the same character(s)
process the strings from left─to─right
if all the same character, display a message saying such
if not all the same character, then:
display a message saying such
display what character is different
only the 1st different character need be displayed
display where the different character is in the string
the above messages can be part of a single message
display the hexadecimal value of the different character
Use (at least) these seven test values (strings):
a string of length 0 (an empty string)
a string of length 3 which contains three blanks
a string of length 1 which contains: 2
a string of length 3 which contains: 333
a string of length 3 which contains: .55
a string of length 6 which contains: tttTTT
a string of length 9 with a blank in the middle: 4444 444k
Show all output here on this page.
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"
func analyze(s string) {
chars := []rune(s)
le := len(chars)
fmt.Printf("Analyzing %q which has a length of %d:\n", s, le)
if le > 1 {
for i := 1; i < le; i++ {
if chars[i] != chars[i-1] {
fmt.Println(" Not all characters in the string are the same.")
fmt.Printf(" %q (%#[1]x) is different at position %d.\n\n", chars[i], i+1)
return
}
}
}
fmt.Println(" All characters in the string are the same.\n")
}
func main() {
strings := []string{
"",
" ",
"2",
"333",
".55",
"tttTTT",
"4444 444k",
"pépé",
"🐶🐶🐺🐶",
"🎄🎄🎄🎄",
}
for _, s := range strings {
analyze(s)
}
} |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a round table with five individual seats. For eating each philosopher needs two forks (the resources). There are five forks on the table, one left and one right of each seat. When a philosopher cannot grab both forks it sits and waits. Eating takes random time, then the philosopher puts the forks down and leaves the dining room. After spending some random time thinking about the nature of the universe, he again becomes hungry, and the circle repeats itself.
It can be observed that a straightforward solution, when forks are implemented by semaphores, is exposed to deadlock. There exist two deadlock states when all five philosophers are sitting at the table holding one fork each. One deadlock state is when each philosopher has grabbed the fork left of him, and another is when each has the fork on his right.
There are many solutions of the problem, program at least one, and explain how the deadlock is prevented.
| #Modula-3 | Modula-3 | MODULE DiningPhilosophers EXPORTS Main;
IMPORT IO, Random, Thread;
CONST
PartySize = 5; (* modify for more/fewer philosophers *)
TYPE
Closure = Thread.Closure OBJECT
(* thread information *)
which: [1..PartySize]; (* identifies the thread *)
OVERRIDES
apply := Live; (* procedure to execute *)
END;
VAR
(* how long to eat/think *)
random: Random.T;
(* controls access to resources *)
test := NEW(MUTEX);
forks := NEW(Thread.Condition); (* condition variable, used for signaling *)
forkAvailable := ARRAY[1..PartySize] OF BOOLEAN {
TRUE, TRUE, TRUE, TRUE, TRUE
};
(* the philosophers/tasks *)
thread: ARRAY[1..PartySize] OF Thread.T;
name := ARRAY[1..PartySize] OF TEXT {
"Aristotle", "Kant", "Spinoza", "Marx", "Russell"
};
PROCEDURE PlaceAvailable(): CARDINAL =
(*
Determines whether a place is available at the table.
If so, returns the place number. Otherwise, returns 0.
We consider a place available if and only if *both* forks are free.
*)
BEGIN
FOR i := 1 TO PartySize DO
IF forkAvailable[i] AND forkAvailable[((i+1) MOD PartySize) + 1] THEN
RETURN i;
END;
END;
RETURN 0;
END PlaceAvailable;
PROCEDURE Live(philosopher: Closure): REFANY =
(* philosophers eat, sleep, ... and that's about it *)
VAR
place: CARDINAL;
BEGIN
WITH which = philosopher.which DO
WHILE TRUE DO
(* first make sure a place is available: both forks must be free! *)
LOCK test DO
place := PlaceAvailable();
(* if not, release mutex and use condition variable to wait for one *)
WHILE place = 0 DO
IO.Put(name[which]); IO.Put(" starving!\n");
Thread.Wait(test, forks);
(* in Modula-3 we arrive here only if we have the lock again *)
place := PlaceAvailable();
END;
(* a place has come available! seize the forks while mutex is locked *)
forkAvailable[place] := FALSE;
forkAvailable[(place MOD PartySize) + 1] := FALSE;
IO.Put(name[which]); IO.Put(" eating at place "); IO.PutInt(place);
IO.PutChar('\n');
END;
Thread.Pause(FLOAT(random.integer(1,3), LONGREAL));
(* put down the forks *)
forkAvailable[place] := TRUE;
forkAvailable[(place MOD PartySize) + 1] := TRUE;
Thread.Signal(forks); (* signal the condition variable *)
LOCK test DO
IO.Put(name[which]); IO.Put(" thinking\n");
END;
Thread.Pause(FLOAT(random.integer(1,3), LONGREAL));
END; (* WHILE *)
END; (* WITH *)
RETURN NIL;
END Live;
BEGIN
random := NEW(Random.Default).init();
(* bring philosophers to life *)
FOR i := 1 TO PartySize DO
thread[i] := Thread.Fork(NEW(Closure, apply := Live, which := i));
END;
(*
We need to wait, otherwise the program will terminate,
and the philosophers with it. Technically we could wait
for just one philosopher, but in the interest of symmetry...
*)
FOR i := 1 TO PartySize DO
EVAL Thread.Join(thread[i]);
END;
END DiningPhilosophers. |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Maple | Maple | convertDiscordian := proc(year, month, day)
local days31, days30, daysThisYear, i, dYear, dMonth, dDay, seasons, week, dayOfWeek;
days31 := [1, 3, 5, 7, 8, 10, 12];
days30 := [4, 6, 9, 11];
if month < 1 or month >12 then
error "Invalid month: %1", month;
end if;
if (member(month, days31) and day > 31) or (member(month, days30) and day > 30) or (month = 2 and day > 29) or day < 1 then
error "Invalid date: %1", day;
end if;
dYear := year + 1166;
if month = 2 and day = 29 then
printf("The date is St. Tib's Day, YOLD %a.\n", dYear);
else
seasons := ["Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath"];
week := ["Sweetmorn", "Boomtime", "Pungenday", "Prickle-Prickle", "Setting Orange"];
daysThisYear := 0;
for i to month-1 do
if member(i, days31) then
daysThisYear := daysThisYear + 31;
elif member(i, days30) then
daysThisYear := daysThisYear + 30;
else
daysThisYear := daysThisYear + 28;
end if;
end do;
daysThisYear := daysThisYear + day -1;
dMonth := seasons[trunc((daysThisYear) / 73)+1];
dDay := daysThisYear mod 73 +1;
dayOfWeek := week[daysThisYear mod 5 +1];
printf("The date is %s %s %s, YOLD %a.\n", dayOfWeek, dMonth, convert(dDay, ordinal), dYear);
end if;
end proc:
convertDiscordian (2016, 1, 1);
convertDiscordian (2016, 2, 29);
convertDiscordian (2016, 12, 31); |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path problem for a graph with non-negative edge path costs, producing a shortest path tree.
This algorithm is often used in routing and as a subroutine in other graph algorithms.
For a given source vertex (node) in the graph, the algorithm finds the path with lowest cost (i.e. the shortest path) between that vertex and every other vertex.
For instance
If the vertices of the graph represent cities and edge path costs represent driving distances between pairs of cities connected by a direct road, Dijkstra's algorithm can be used to find the shortest route between one city and all other cities.
As a result, the shortest path first is widely used in network routing protocols, most notably:
IS-IS (Intermediate System to Intermediate System) and
OSPF (Open Shortest Path First).
Important note
The inputs to Dijkstra's algorithm are a directed and weighted graph consisting of 2 or more nodes, generally represented by:
an adjacency matrix or list, and
a start node.
A destination node is not specified.
The output is a set of edges depicting the shortest path to each destination node.
An example, starting with
a──►b, cost=7, lastNode=a
a──►c, cost=9, lastNode=a
a──►d, cost=NA, lastNode=a
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►b so a──►b is added to the output.
There is a connection from b──►d so the input is updated to:
a──►c, cost=9, lastNode=a
a──►d, cost=22, lastNode=b
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►c so a──►c is added to the output.
Paths to d and f are cheaper via c so the input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
a──►f, cost=11, lastNode=c
The lowest cost is a──►f so c──►f is added to the output.
The input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
The lowest cost is a──►d so c──►d is added to the output.
There is a connection from d──►e so the input is updated to:
a──►e, cost=26, lastNode=d
Which just leaves adding d──►e to the output.
The output should now be:
[ d──►e
c──►d
c──►f
a──►c
a──►b ]
Task
Implement a version of Dijkstra's algorithm that outputs a set of edges depicting the shortest path to each reachable node from an origin.
Run your program with the following directed graph starting at node a.
Write a program which interprets the output from the above and use it to output the shortest path from node a to nodes e and f.
Vertices
Number
Name
1
a
2
b
3
c
4
d
5
e
6
f
Edges
Start
End
Cost
a
b
7
a
c
9
a
f
14
b
c
10
b
d
15
c
d
11
c
f
2
d
e
6
e
f
9
You can use numbers or names to identify vertices in your program.
See also
Dijkstra's Algorithm vs. A* Search vs. Concurrent Dijkstra's Algorithm (youtube)
| #Nim | Nim |
# Dijkstra algorithm.
from algorithm import reverse
import sets
import strformat
import tables
type
Edge = tuple[src, dst: string; cost: int]
Graph = object
vertices: HashSet[string]
neighbours: Table[string, seq[tuple[dst: string, cost: float]]]
#---------------------------------------------------------------------------------------------------
proc initGraph(edges: openArray[Edge]): Graph =
## Initialize a graph from an edge list.
## Use floats for costs in order to compare to Inf value.
for (src, dst, cost) in edges:
result.vertices.incl(src)
result.vertices.incl(dst)
result.neighbours.mgetOrPut(src, @[]).add((dst, cost.toFloat))
#---------------------------------------------------------------------------------------------------
proc dijkstraPath(graph: Graph; first, last: string): seq[string] =
## Find the path from "first" to "last" which minimizes the cost.
var dist = initTable[string, float]()
var previous = initTable[string, string]()
var notSeen = graph.vertices
for vertex in graph.vertices:
dist[vertex] = Inf
dist[first] = 0
while notSeen.card > 0:
# Search vertex with minimal distance.
var vertex1: string
var mindist = Inf
for vertex in notSeen:
if dist[vertex] < mindist:
vertex1 = vertex
mindist = dist[vertex]
if vertex1 == last:
break
notSeen.excl(vertex1)
# Find shortest paths to neighbours.
for (vertex2, cost) in graph.neighbours.getOrDefault(vertex1):
if vertex2 in notSeen:
let altdist = dist[vertex1] + cost
if altdist < dist[vertex2]:
# Found a shorter path to go to vertex2.
dist[vertex2] = altdist
previous[vertex2] = vertex1 # To go to vertex2, go through vertex1.
# Build the path.
var vertex = last
while vertex.len > 0:
result.add(vertex)
vertex = previous.getOrDefault(vertex)
result.reverse()
#---------------------------------------------------------------------------------------------------
proc printPath(path: seq[string]) =
## Print a path.
stdout.write(fmt"Shortest path from '{path[0]}' to '{path[^1]}': {path[0]}")
for i in 1..path.high:
stdout.write(fmt" → {path[i]}")
stdout.write('\n')
#---------------------------------------------------------------------------------------------------
let graph = initGraph([("a", "b", 7), ("a", "c", 9), ("a", "f", 14),
("b", "c", 10), ("b", "d", 15), ("c", "d", 11),
("c", "f", 2), ("d", "e", 6), ("e", "f", 9)])
printPath(graph.dijkstraPath("a", "e"))
printPath(graph.dijkstraPath("a", "f"))
|
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displaystyle X}
has only one digit.
The additive persistence is the number of summations required to obtain the single digit.
The task is to calculate the additive persistence and the digital root of a number, e.g.:
627615
{\displaystyle 627615}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
39390
{\displaystyle 39390}
has additive persistence
2
{\displaystyle 2}
and digital root of
6
{\displaystyle 6}
;
588225
{\displaystyle 588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
3
{\displaystyle 3}
;
393900588225
{\displaystyle 393900588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
The digital root may be calculated in bases other than 10.
See
Casting out nines for this wiki's use of this procedure.
Digital root/Multiplicative digital root
Sum digits of an integer
Digital root sequence on OEIS
Additive persistence sequence on OEIS
Iterated digits squaring
| #Haskell | Haskell | import Data.Bifunctor (bimap)
import Data.List (unfoldr)
import Data.Tuple (swap)
digSum :: Int -> Int -> Int
digSum base = sum . unfoldr f
where
f 0 = Nothing
f n = Just (swap (quotRem n base))
digRoot :: Int -> Int -> (Int, Int)
digRoot base =
head .
dropWhile ((>= base) . snd) . iterate (bimap succ (digSum base)) . (,) 0
main :: IO ()
main = do
putStrLn "in base 10:"
mapM_ (print . ((,) <*> digRoot 10)) [627615, 39390, 588225, 393900588225] |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
{\displaystyle 0}
.
While
m
{\displaystyle m}
has more than one digit:
Find a replacement
m
{\displaystyle m}
as the multiplication of the digits of the current value of
m
{\displaystyle m}
.
Increment
i
{\displaystyle i}
.
Return
i
{\displaystyle i}
(= MP) and
m
{\displaystyle m}
(= MDR)
Task
Tabulate the MP and MDR of the numbers 123321, 7739, 893, 899998
Tabulate MDR versus the first five numbers having that MDR, something like:
MDR: [n0..n4]
=== ========
0: [0, 10, 20, 25, 30]
1: [1, 11, 111, 1111, 11111]
2: [2, 12, 21, 26, 34]
3: [3, 13, 31, 113, 131]
4: [4, 14, 22, 27, 39]
5: [5, 15, 35, 51, 53]
6: [6, 16, 23, 28, 32]
7: [7, 17, 71, 117, 171]
8: [8, 18, 24, 29, 36]
9: [9, 19, 33, 91, 119]
Show all output on this page.
Similar
The Product of decimal digits of n page was redirected here, and had the following description
Find the product of the decimal digits of a positive integer n, where n <= 100
The three existing entries for Phix, REXX, and Ring have been moved here, under ===Similar=== headings, feel free to match or ignore them.
References
Multiplicative Digital Root on Wolfram Mathworld.
Multiplicative digital root on The On-Line Encyclopedia of Integer Sequences.
What's special about 277777788888899? - Numberphile video
| #Scala | Scala | import Stream._
object MDR extends App {
def mdr(x: BigInt, base: Int = 10): (BigInt, Long) = {
def multiplyDigits(x: BigInt): BigInt = ((x.toString(base) map (_.asDigit)) :\ BigInt(1))(_*_)
def loop(p: BigInt, c: Long): (BigInt, Long) = if (p < base) (p, c) else loop(multiplyDigits(p), c+1)
loop(multiplyDigits(x), 1)
}
printf("%15s\t%10s\t%s\n","Number","MDR","MP")
printf("%15s\t%10s\t%s\n","======","===","==")
Seq[BigInt](123321, 7739, 893, 899998, BigInt("393900588225"), BigInt("999999999999")) foreach {x =>
val (s, c) = mdr(x)
printf("%15s\t%10s\t%2s\n",x,s,c)
}
println
val mdrs: Stream[Int] => Stream[(Int, BigInt)] = i => i map (x => (x, mdr(x)._1))
println("MDR: [n0..n4]")
println("==== ========")
((for {i <- 0 to 9} yield (mdrs(from(0)) take 11112 toList) filter {_._2 == i})
.map {_ take 5} map {xs => xs map {_._1}}).zipWithIndex
.foreach{p => printf("%3s: [%s]\n",p._2,p._1.mkString(", "))}
} |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of expression are valued.
Examples may be be split into "setup", "problem statement", and "output" sections where the ease and naturalness of stating the problem and getting an answer, as well as the ease and flexibility of modifying the problem are the primary concerns.
Example output should be shown here, as well as any comments on the examples flexibility.
The problem
Baker, Cooper, Fletcher, Miller, and Smith live on different floors of an apartment house that contains only five floors.
Baker does not live on the top floor.
Cooper does not live on the bottom floor.
Fletcher does not live on either the top or the bottom floor.
Miller lives on a higher floor than does Cooper.
Smith does not live on a floor adjacent to Fletcher's.
Fletcher does not live on a floor adjacent to Cooper's.
Where does everyone live?
| #Perl | Perl | use strict;
use warnings;
use feature <state say>;
use List::Util 1.33 qw(pairmap);
use Algorithm::Permute qw(permute);
our %predicates = (
# | object | sprintf format for Perl expression |
# --------------------+-----------+------------------------------------+
'on bottom' => [ '' , '$f[%s] == 1' ],
'on top' => [ '' , '$f[%s] == @f' ],
'lower than' => [ 'person' , '$f[%s] < $f[%s]' ],
'higher than' => [ 'person' , '$f[%s] > $f[%s]' ],
'directly below' => [ 'person' , '$f[%s] == $f[%s] - 1' ],
'directly above' => [ 'person' , '$f[%s] == $f[%s] + 1' ],
'adjacent to' => [ 'person' , 'abs($f[%s] - $f[%s]) == 1' ],
'on' => [ 'ordinal' , '$f[%s] == \'%s\'' ],
);
our %nouns = (
'person' => qr/[a-z]+/i,
'ordinal' => qr/1st | 2nd | 3rd | \d+th/x,
);
sub parse_and_solve {
my @facts = @_;
state $parser = qr/^(?<subj>$nouns{person}) (?<not>not )?(?|@{[
join '|', pairmap {
"(?<pred>$a)" .
($b->[0] ? " (?<obj>$nouns{$b->[0]})" : '')
} %predicates
]})$/;
my (@expressions, %ids, $i);
my $id = sub { defined $_[0] ? $ids{$_[0]} //= $i++ : () };
foreach (@facts) {
/$parser/ or die "Cannot parse '$_'\n";
my $pred = $predicates{$+{pred}};
{ no warnings;
my $expr = '(' . sprintf($pred->[1], $id->($+{subj}),
$pred->[0] eq 'person' ? $id->($+{obj}) : $+{obj}). ')';
$expr = '!' . $expr if $+{not};
push @expressions, $expr;
}
}
my @f = 1..$i;
eval '
permute {
say join(", ", pairmap { "$f[$b] $a" } %ids)
if ('.join(' && ', @expressions).');
} @f;';
} |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot product of two vectors directly:
each vector must be the same length
multiply corresponding terms from each vector
sum the products (to produce the answer)
Related task
Vector products
| #Haskell | Haskell | dotp :: Num a => [a] -> [a] -> a
dotp a b | length a == length b = sum (zipWith (*) a b)
| otherwise = error "Vector sizes must match"
main = print $ dotp [1, 3, -5] [4, -2, -1] -- prints 3 |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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
| #jq | jq | # Assume $c is specified as a single character correctly
def squeeze($c): gsub("[\($c)]+"; $c);
def Guillemets: "«««\(.)»»»";
def Squeeze(s; $c):
"Squeeze character: \($c)",
(s | "Original: \(Guillemets) has length \(length)",
(squeeze($c) | "result is \(Guillemets) with length \(length)")),
""; |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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_2 | J | NB. Note |.!.1 here instead of the APL version's 1 , }. to more elegantly handle the null case in J
sq =: ] #~ ~: +. _1 |.!.1 ] ~: 1 |. ] |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to improve performance. In each case the experiment begins with the funnel positioned directly over the target.
Rule 1: The funnel remains directly above the target.
Rule 2: Adjust the funnel position by shifting the target to compensate after each drop. E.g. If the last drop missed 1 cm east, move the funnel 1 cm to the west of its current position.
Rule 3: As rule 2, but first move the funnel back over the target, before making the adjustment. E.g. If the funnel is 2 cm north, and the marble lands 3 cm north, move the funnel 3 cm south of the target.
Rule 4: The funnel is moved directly over the last place a marble landed.
Apply the four rules to the set of 50 pseudorandom displacements provided (e.g in the Racket solution) for the dxs and dys. Output: calculate the mean and standard-deviations of the resulting x and y values for each rule.
Note that rules 2, 3, and 4 give successively worse results. Trying to deterministically compensate for a random process is counter-productive, but -- according to Deming -- quite a popular pastime: see the Further Information, below for examples.
Stretch goal 1: Generate fresh pseudorandom data. The radial displacement of the drop from the funnel position is given by a Gaussian distribution (standard deviation is 1.0) and the angle of displacement is uniformly distributed.
Stretch goal 2: Show scatter plots of all four results.
Further information
Further explanation and interpretation
Video demonstration of the funnel experiment at the Mayo Clinic. | #Julia | Julia | # Run from Julia REPL to see the plots.
using Statistics, Distributions, Plots
const racket_xdata = [-0.533, 0.270, 0.859, -0.043, -0.205, -0.127, -0.071, 0.275, 1.251, -0.231,
-0.401, 0.269, 0.491, 0.951, 1.150, 0.001, -0.382, 0.161, 0.915, 2.080, -2.337,
0.034, -0.126, 0.014, 0.709, 0.129, -1.093, -0.483, -1.193, 0.020, -0.051,
0.047, -0.095, 0.695, 0.340, -0.182, 0.287, 0.213, -0.423, -0.021, -0.134, 1.798,
0.021, -1.099, -0.361, 1.636, -1.134, 1.315, 0.201, 0.034, 0.097, -0.170, 0.054,
-0.553, -0.024, -0.181, -0.700, -0.361, -0.789, 0.279, -0.174, -0.009, -0.323,
-0.658, 0.348, -0.528, 0.881, 0.021, -0.853, 0.157, 0.648, 1.774, -1.043, 0.051,
0.021, 0.247, -0.310, 0.171, 0.000, 0.106, 0.024, -0.386, 0.962, 0.765, -0.125,
-0.289, 0.521, 0.017, 0.281, -0.749, -0.149, -2.436, -0.909, 0.394, -0.113, -0.598,
0.443, -0.521, -0.799, 0.087]
const racket_ydata = [0.136, 0.717, 0.459, -0.225, 1.392, 0.385, 0.121, -0.395, 0.490, -0.682, -0.065,
0.242, -0.288, 0.658, 0.459, 0.000, 0.426, 0.205, -0.765, -2.188, -0.742, -0.010,
0.089, 0.208, 0.585, 0.633, -0.444, -0.351, -1.087, 0.199, 0.701, 0.096, -0.025,
-0.868, 1.051, 0.157, 0.216, 0.162, 0.249, -0.007, 0.009, 0.508, -0.790, 0.723,
0.881, -0.508, 0.393, -0.226, 0.710, 0.038, -0.217, 0.831, 0.480, 0.407, 0.447,
-0.295, 1.126, 0.380, 0.549, -0.445, -0.046, 0.428, -0.074, 0.217, -0.822, 0.491,
1.347, -0.141, 1.230, -0.044, 0.079, 0.219, 0.698, 0.275, 0.056, 0.031, 0.421, 0.064,
0.721, 0.104, -0.729, 0.650, -1.103, 0.154, -1.720, 0.051, -0.385, 0.477, 1.537,
-0.901, 0.939, -0.411, 0.341, -0.411, 0.106, 0.224, -0.947, -1.424, -0.542, -1.032]
const rules = [(x, y, dx, dy) -> [0, 0], (x, y, dx, dy) -> [-dx, -dy],
(x, y, dx, dy) -> [-x - dx, -y - dy], (x, y, dx, dy) -> [x + dx, y + dy]]
const plots, colors = plot(layout=(1,2)), [:red, :green, :blue, :yellow]
function makedata()
radius_angles = zip(rand(Normal(), 100), rand(Uniform(-π, π), 100))
zip([z[1] * cos(z[2]) for z in radius_angles], [z[1] * sin(z[2]) for z in radius_angles])
end
function testfunnel(useracket=true)
for (i, rule) in enumerate(rules)
origin = [0.0, 0.0]
xvec, yvec = Float64[], Float64[]
for point in (useracket ? zip(racket_xdata, racket_ydata) : makedata())
push!(xvec, origin[1] + point[1])
push!(yvec, origin[2] + point[2])
origin .= rule(origin[1], origin[2], point[1], point[2])
end
println("Rule $i results:")
println("mean x: ", round(mean(xvec), digits=4), " std x: ", round(std(xvec, corrected=false), digits=4),
" mean y: ", round(mean(yvec), digits=4), " std y: ", round(std(yvec, corrected=false), digits=4))
scatter!(xvec, yvec, color=colors[i], subplot=(useracket ? 1 : 2),
title= useracket ? "Racket Data" : "Random Data", label="Rule $i")
end
end
println("\nUsing Racket data.")
testfunnel()
println("\nUsing new data.")
testfunnel(false)
display(plots)
|
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to improve performance. In each case the experiment begins with the funnel positioned directly over the target.
Rule 1: The funnel remains directly above the target.
Rule 2: Adjust the funnel position by shifting the target to compensate after each drop. E.g. If the last drop missed 1 cm east, move the funnel 1 cm to the west of its current position.
Rule 3: As rule 2, but first move the funnel back over the target, before making the adjustment. E.g. If the funnel is 2 cm north, and the marble lands 3 cm north, move the funnel 3 cm south of the target.
Rule 4: The funnel is moved directly over the last place a marble landed.
Apply the four rules to the set of 50 pseudorandom displacements provided (e.g in the Racket solution) for the dxs and dys. Output: calculate the mean and standard-deviations of the resulting x and y values for each rule.
Note that rules 2, 3, and 4 give successively worse results. Trying to deterministically compensate for a random process is counter-productive, but -- according to Deming -- quite a popular pastime: see the Further Information, below for examples.
Stretch goal 1: Generate fresh pseudorandom data. The radial displacement of the drop from the funnel position is given by a Gaussian distribution (standard deviation is 1.0) and the angle of displacement is uniformly distributed.
Stretch goal 2: Show scatter plots of all four results.
Further information
Further explanation and interpretation
Video demonstration of the funnel experiment at the Mayo Clinic. | #Kotlin | Kotlin | // version 1.1.3
typealias Rule = (Double, Double) -> Double
val dxs = doubleArrayOf(
-0.533, 0.270, 0.859, -0.043, -0.205, -0.127, -0.071, 0.275,
1.251, -0.231, -0.401, 0.269, 0.491, 0.951, 1.150, 0.001,
-0.382, 0.161, 0.915, 2.080, -2.337, 0.034, -0.126, 0.014,
0.709, 0.129, -1.093, -0.483, -1.193, 0.020, -0.051, 0.047,
-0.095, 0.695, 0.340, -0.182, 0.287, 0.213, -0.423, -0.021,
-0.134, 1.798, 0.021, -1.099, -0.361, 1.636, -1.134, 1.315,
0.201, 0.034, 0.097, -0.170, 0.054, -0.553, -0.024, -0.181,
-0.700, -0.361, -0.789, 0.279, -0.174, -0.009, -0.323, -0.658,
0.348, -0.528, 0.881, 0.021, -0.853, 0.157, 0.648, 1.774,
-1.043, 0.051, 0.021, 0.247, -0.310, 0.171, 0.000, 0.106,
0.024, -0.386, 0.962, 0.765, -0.125, -0.289, 0.521, 0.017,
0.281, -0.749, -0.149, -2.436, -0.909, 0.394, -0.113, -0.598,
0.443, -0.521, -0.799, 0.087
)
val dys = doubleArrayOf(
0.136, 0.717, 0.459, -0.225, 1.392, 0.385, 0.121, -0.395,
0.490, -0.682, -0.065, 0.242, -0.288, 0.658, 0.459, 0.000,
0.426, 0.205, -0.765, -2.188, -0.742, -0.010, 0.089, 0.208,
0.585, 0.633, -0.444, -0.351, -1.087, 0.199, 0.701, 0.096,
-0.025, -0.868, 1.051, 0.157, 0.216, 0.162, 0.249, -0.007,
0.009, 0.508, -0.790, 0.723, 0.881, -0.508, 0.393, -0.226,
0.710, 0.038, -0.217, 0.831, 0.480, 0.407, 0.447, -0.295,
1.126, 0.380, 0.549, -0.445, -0.046, 0.428, -0.074, 0.217,
-0.822, 0.491, 1.347, -0.141, 1.230, -0.044, 0.079, 0.219,
0.698, 0.275, 0.056, 0.031, 0.421, 0.064, 0.721, 0.104,
-0.729, 0.650, -1.103, 0.154, -1.720, 0.051, -0.385, 0.477,
1.537, -0.901, 0.939, -0.411, 0.341, -0.411, 0.106, 0.224,
-0.947, -1.424, -0.542, -1.032
)
fun funnel(da: DoubleArray, rule: Rule): DoubleArray {
var x = 0.0
val result = DoubleArray(da.size)
for ((i, d) in da.withIndex()) {
result[i] = x + d
x = rule(x, d)
}
return result
}
fun mean(da: DoubleArray) = da.average()
fun stdDev(da: DoubleArray): Double {
val m = mean(da)
return Math.sqrt(da.map { (it - m) * (it - m) }.average())
}
fun experiment(label: String, rule: Rule) {
val rxs = funnel(dxs, rule)
val rys = funnel(dys, rule)
println("$label : x y")
println("Mean : ${"%7.4f, %7.4f".format(mean(rxs), mean(rys))}")
println("Std Dev : ${"%7.4f, %7.4f".format(stdDev(rxs), stdDev(rys))}")
println()
}
fun main(args: Array<String>) {
experiment("Rule 1") { _, _ -> 0.0 }
experiment("Rule 2") { _, dz -> -dz }
experiment("Rule 3") { z, dz -> -(z + dz) }
experiment("Rule 4") { z, dz -> z + dz }
} |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and must add up to 12.
The Chief of the Police doesn't like odd numbers and wants to have an even number for his department.
Task
Write a computer program which outputs all valid combinations.
Possible output (for the 1st and 14th solutions):
--police-- --sanitation-- --fire--
2 3 7
6 5 1
| #ALGOL_W | ALGOL W | begin
% show possible department number allocations for police, sanitation and fire departments %
% the police department number must be even, all department numbers in the range 1 .. 7 %
% the sum of the department numbers must be 12 %
integer MAX_DEPARTMENT_NUMBER, DEPARTMENT_SUM;
MAX_DEPARTMENT_NUMBER := 7;
DEPARTMENT_SUM := 12;
write( "police sanitation fire" );
for police := 2 step 2 until MAX_DEPARTMENT_NUMBER do begin
for sanitation := 1 until MAX_DEPARTMENT_NUMBER do begin
IF sanitation not = police then begin
integer fire;
fire := ( DEPARTMENT_SUM - police ) - sanitation;
if fire > 0 and fire <= MAX_DEPARTMENT_NUMBER and fire not = sanitation and fire not = police then begin
write( s_w := 0, i_w := 6, police, i_w := 11, sanitation, i_w := 5, fire )
end if_valid_combination
end if_sanitation_ne_police
end for_sanitation
end for_police
end. |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and must add up to 12.
The Chief of the Police doesn't like odd numbers and wants to have an even number for his department.
Task
Write a computer program which outputs all valid combinations.
Possible output (for the 1st and 14th solutions):
--police-- --sanitation-- --fire--
2 3 7
6 5 1
| #APL | APL | 'PSF'⍪(⊢(⌿⍨)((∪≡⊢)¨↓∧(0=2|1⌷[2]⊢)∧12=+/))↑,⍳3/7 |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects responsibilities:
Delegator:
Keep an optional delegate instance.
Implement "operation" method, returning the delegate "thing" if the delegate respond to "thing", or the string "default implementation".
Delegate:
Implement "thing" and return the string "delegate implementation"
Show how objects are created and used. First, without a delegate, then with a delegate that does not implement "thing", and last with a delegate that implements "thing".
| #Clojure | Clojure | (defprotocol Thing
(thing [_]))
(defprotocol Operation
(operation [_]))
(defrecord Delegator [delegate]
Operation
(operation [_] (try (thing delegate) (catch IllegalArgumentException e "default implementation"))))
(defrecord Delegate []
Thing
(thing [_] "delegate implementation")) |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects responsibilities:
Delegator:
Keep an optional delegate instance.
Implement "operation" method, returning the delegate "thing" if the delegate respond to "thing", or the string "default implementation".
Delegate:
Implement "thing" and return the string "delegate implementation"
Show how objects are created and used. First, without a delegate, then with a delegate that does not implement "thing", and last with a delegate that implements "thing".
| #CoffeeScript | CoffeeScript |
class Delegator
operation: ->
if @delegate and typeof (@delegate.thing) is "function"
return @delegate.thing()
"default implementation"
class Delegate
thing: ->
"Delegate Implementation"
testDelegator = ->
# Delegator with no delegate.
a = new Delegator()
console.log a.operation()
# Delegator with delegate not implementing "thing"
a.delegate = "A delegate may be any object"
console.log a.operation()
# Delegator with delegate that does implement "thing"
a.delegate = new Delegate()
console.log a.operation()
testDelegator()
|
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)
(0,0),(5,0),(2.5,5) and (0,4),(2.5,-1),(5,4)
(0,0),(1,1),(0,2) and (2,1),(3,0),(3,2)
(0,0),(1,1),(0,2) and (2,1),(3,-2),(3,4)
Optionally, see what the result is when only a single corner is in contact (there is no definitive correct answer):
(0,0),(1,0),(0,1) and (1,0),(2,0),(1,1)
| #Groovy | Groovy | import java.util.function.BiFunction
class TriangleOverlap {
private static class Pair {
double first
double second
Pair(double first, double second) {
this.first = first
this.second = second
}
@Override
String toString() {
return String.format("(%s, %s)", first, second)
}
}
private static class Triangle {
Pair p1, p2, p3
Triangle(Pair p1, Pair p2, Pair p3) {
this.p1 = p1
this.p2 = p2
this.p3 = p3
}
@Override
String toString() {
return String.format("Triangle: %s, %s, %s", p1, p2, p3)
}
}
private static double det2D(Triangle t) {
Pair p1 = t.p1
Pair p2 = t.p2
Pair p3 = t.p3
return p1.first * (p2.second - p3.second) + p2.first * (p3.second - p1.second) + p3.first * (p1.second - p2.second)
}
private static void checkTriWinding(Triangle t, boolean allowReversed) {
double detTri = det2D(t)
if (detTri < 0.0) {
if (allowReversed) {
Pair a = t.p3
t.p3 = t.p2
t.p2 = a
} else throw new RuntimeException("Triangle has wrong winding direction")
}
}
private static boolean boundaryCollideChk(Triangle t, double eps) {
return det2D(t) < eps
}
private static boolean boundaryDoesntCollideChk(Triangle t, double eps) {
return det2D(t) <= eps
}
private static boolean triTri2D(Triangle t1, Triangle t2) {
return triTri2D(t1, t2, 0.0, false, true)
}
private static boolean triTri2D(Triangle t1, Triangle t2, double eps, boolean allowedReversed) {
return triTri2D(t1, t2, eps, allowedReversed, true)
}
private static boolean triTri2D(Triangle t1, Triangle t2, double eps, boolean allowedReversed, boolean onBoundary) {
// Triangles must be expressed anti-clockwise
checkTriWinding(t1, allowedReversed)
checkTriWinding(t2, allowedReversed)
// 'onBoundary' determines whether points on boundary are considered as colliding or not
BiFunction<Triangle, Double, Boolean> chkEdge = onBoundary ? TriangleOverlap.&boundaryCollideChk : TriangleOverlap.&boundaryDoesntCollideChk
Pair[] lp1 = [t1.p1, t1.p2, t1.p3]
Pair[] lp2 = [t2.p1, t2.p2, t2.p3]
// for each edge E of t1
for (int i = 0; i < 3; ++i) {
int j = (i + 1) % 3
// Check all points of t2 lay on the external side of edge E.
// If they do, the triangles do not overlap.
if (chkEdge.apply(new Triangle(lp1[i], lp1[j], lp2[0]), eps) &&
chkEdge.apply(new Triangle(lp1[i], lp1[j], lp2[1]), eps) &&
chkEdge.apply(new Triangle(lp1[i], lp1[j], lp2[2]), eps)) return false
}
// for each edge E of t2
for (int i = 0; i < 3; ++i) {
int j = (i + 1) % 3
// Check all points of t1 lay on the external side of edge E.
// If they do, the triangles do not overlap.
if (chkEdge.apply(new Triangle(lp2[i], lp2[j], lp1[0]), eps) &&
chkEdge.apply(new Triangle(lp2[i], lp2[j], lp1[1]), eps) &&
chkEdge.apply(new Triangle(lp2[i], lp2[j], lp1[2]), eps)) return false
}
// The triangles overlap
return true
}
static void main(String[] args) {
Triangle t1 = new Triangle(new Pair(0.0, 0.0), new Pair(5.0, 0.0), new Pair(0.0, 5.0))
Triangle t2 = new Triangle(new Pair(0.0, 0.0), new Pair(5.0, 0.0), new Pair(0.0, 6.0))
printf("%s and\n%s\n", t1, t2)
if (triTri2D(t1, t2)) {
println("overlap")
} else {
println("do not overlap")
}
// need to allow reversed for this pair to avoid exception
t1 = new Triangle(new Pair(0.0, 0.0), new Pair(0.0, 5.0), new Pair(5.0, 0.0))
t2 = t1
printf("\n%s and\n%s\n", t1, t2)
if (triTri2D(t1, t2, 0.0, true)) {
println("overlap (reversed)")
} else {
println("do not overlap")
}
t1 = new Triangle(new Pair(0.0, 0.0), new Pair(5.0, 0.0), new Pair(0.0, 5.0))
t2 = new Triangle(new Pair(-10.0, 0.0), new Pair(-5.0, 0.0), new Pair(-1.0, 6.0))
printf("\n%s and\n%s\n", t1, t2)
if (triTri2D(t1, t2)) {
println("overlap")
} else {
println("do not overlap")
}
t1.p3 = new Pair(2.5, 5.0)
t2 = new Triangle(new Pair(0.0, 4.0), new Pair(2.5, -1.0), new Pair(5.0, 4.0))
printf("\n%s and\n%s\n", t1, t2)
if (triTri2D(t1, t2)) {
println("overlap")
} else {
println("do not overlap")
}
t1 = new Triangle(new Pair(0.0, 0.0), new Pair(1.0, 1.0), new Pair(0.0, 2.0))
t2 = new Triangle(new Pair(2.0, 1.0), new Pair(3.0, 0.0), new Pair(3.0, 2.0))
printf("\n%s and\n%s\n", t1, t2)
if (triTri2D(t1, t2)) {
println("overlap")
} else {
println("do not overlap")
}
t2 = new Triangle(new Pair(2.0, 1.0), new Pair(3.0, -2.0), new Pair(3.0, 4.0))
printf("\n%s and\n%s\n", t1, t2)
if (triTri2D(t1, t2)) {
println("overlap")
} else {
println("do not overlap")
}
t1 = new Triangle(new Pair(0.0, 0.0), new Pair(1.0, 0.0), new Pair(0.0, 1.0))
t2 = new Triangle(new Pair(1.0, 0.0), new Pair(2.0, 0.0), new Pair(1.0, 1.1))
printf("\n%s and\n%s\n", t1, t2)
println("which have only a single corner in contact, if boundary points collide")
if (triTri2D(t1, t2)) {
println("overlap")
} else {
println("do not overlap")
}
printf("\n%s and\n%s\n", t1, t2)
println("which have only a single corner in contact, if boundary points do not collide")
if (triTri2D(t1, t2, 0.0, false, false)) {
println("overlap")
} else {
println("do not overlap")
}
}
} |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #BASIC | BASIC |
KILL "INPUT.TXT"
KILL "C:\INPUT.TXT"
SHELL "RMDIR /S /Q DIR"
SHELL "RMDIR /S /Q C:\DIR"
|
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Batch_File | Batch File | del input.txt
rd /s /q docs
del \input.txt
rd /s /q \docs |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
perm
(
A
)
=
∑
σ
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \operatorname {perm} (A)=\sum _{\sigma }\prod _{i=1}^{n}M_{i,\sigma _{i}}}
In both cases the sum is over the permutations
σ
{\displaystyle \sigma }
of the permutations of 1, 2, ..., n. (A permutation's sign is 1 if there are an even number of inversions and -1 otherwise; see parity of a permutation.)
More efficient algorithms for the determinant are known: LU decomposition, see for example wp:LU decomposition#Computing the determinant. Efficient methods for calculating the permanent are not known.
Related task
Permutations by swapping
| #Go | Go | package main
import (
"fmt"
"permute"
)
func determinant(m [][]float64) (d float64) {
p := make([]int, len(m))
for i := range p {
p[i] = i
}
it := permute.Iter(p)
for s := it(); s != 0; s = it() {
pr := 1.
for i, σ := range p {
pr *= m[i][σ]
}
d += float64(s) * pr
}
return
}
func permanent(m [][]float64) (d float64) {
p := make([]int, len(m))
for i := range p {
p[i] = i
}
it := permute.Iter(p)
for s := it(); s != 0; s = it() {
pr := 1.
for i, σ := range p {
pr *= m[i][σ]
}
d += pr
}
return
}
var m2 = [][]float64{
{1, 2},
{3, 4}}
var m3 = [][]float64{
{2, 9, 4},
{7, 5, 3},
{6, 1, 8}}
func main() {
fmt.Println(determinant(m2), permanent(m2))
fmt.Println(determinant(m3), permanent(m3))
} |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Delphi | Delphi | program DivideByZero;
{$APPTYPE CONSOLE}
uses SysUtils;
var
a, b: Integer;
begin
a := 1;
b := 0;
try
WriteLn(a / b);
except
on e: EZeroDivide do
Writeln(e.Message);
end;
end. |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #D.C3.A9j.C3.A0_Vu | Déjà Vu | divcheck x y:
true
try:
drop / x y
catch value-error:
not
if divcheck 1 0:
!print "Okay"
else:
!print "Division by zero" |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #C.23 | C# | public static bool IsNumeric(string s)
{
double Result;
return double.TryParse(s, out Result); // TryParse routines were added in Framework version 2.0.
}
string value = "123";
if (IsNumeric(value))
{
// do something
} |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #C.2B.2B | C++ | #include <sstream> // for istringstream
using namespace std;
bool isNumeric( const char* pszInput, int nNumberBase )
{
istringstream iss( pszInput );
if ( nNumberBase == 10 )
{
double dTestSink;
iss >> dTestSink;
}
else if ( nNumberBase == 8 || nNumberBase == 16 )
{
int nTestSink;
iss >> ( ( nNumberBase == 8 ) ? oct : hex ) >> nTestSink;
}
else
return false;
// was any input successfully consumed/converted?
if ( ! iss )
return false;
// was all the input successfully consumed/converted?
return ( iss.rdbuf()->in_avail() == 0 );
}
|
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as unique
process the strings from left─to─right
if unique, display a message saying such
if not unique, then:
display a message saying such
display what character is duplicated
only the 1st non─unique character need be displayed
display where "both" duplicated characters are in the string
the above messages can be part of a single message
display the hexadecimal value of the duplicated character
Use (at least) these five test values (strings):
a string of length 0 (an empty string)
a string of length 1 which is a single period (.)
a string of length 6 which contains: abcABC
a string of length 7 which contains a blank in the middle: XYZ ZYX
a string of length 36 which doesn't contain the letter "oh":
1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ
Show all output here on this page.
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
| #Erlang | Erlang |
-module(string_examples).
-export([all_unique/1, all_unique_examples/0]).
all_unique(String) ->
CharPosPairs = lists:zip(String, lists:seq(1, length(String))),
Duplicates = [{Char1, Pos1, Pos2} || {Char1, Pos1} <- CharPosPairs,
{Char2, Pos2} <- CharPosPairs,
Char1 =:= Char2,
Pos2 > Pos1],
case Duplicates of
[] ->
all_unique;
[{Char, P1, P2}|_] ->
{not_all_unique, Char, P1, P2}
end.
all_unique_examples() ->
lists:foreach(fun (Str) ->
io:format("String \"~ts\" (length ~p): ",
[Str, length(Str)]),
case all_unique(Str) of
all_unique ->
io:format("All characters unique.~n");
{not_all_unique, Char, P1, P2} ->
io:format("First duplicate is '~tc' (0x~.16b)"
" at positions ~p and ~p.~n",
[Char, Char, P1, P2])
end
end,
["", ".", "abcABC", "XYZ ZYX",
"1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ"]).
|
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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 |
String.prototype.collapse = function() {
let str = this;
for (let i = 0; i < str.length; i++) {
while (str[i] == str[i+1]) str = str.substr(0,i) + str.substr(i+1);
}
return str;
}
// testing
let strings = [
'',
'"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ',
'..1111111111111111111111111111111111111111111111111111111111111117777888',
`I never give 'em hell, I just tell the truth, and they think it's hell. `,
' --- Harry S Truman '
];
for (let i = 0; i < strings.length; i++) {
let str = strings[i], col = str.collapse();
console.log(`«««${str}»»» (${str.length})`);
console.log(`«««${col}»»» (${col.length})`);
}
|
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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
| #jq | jq | # Input: an array
# Output: a stream
def uniq: foreach .[] as $x ({x:nan, y:.[0]}; {x:$x, y:.x}; select(.x != .y) | .x);
def collapse: explode | [uniq] | implode; |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as all the same character(s)
process the strings from left─to─right
if all the same character, display a message saying such
if not all the same character, then:
display a message saying such
display what character is different
only the 1st different character need be displayed
display where the different character is in the string
the above messages can be part of a single message
display the hexadecimal value of the different character
Use (at least) these seven test values (strings):
a string of length 0 (an empty string)
a string of length 3 which contains three blanks
a string of length 1 which contains: 2
a string of length 3 which contains: 333
a string of length 3 which contains: .55
a string of length 6 which contains: tttTTT
a string of length 9 with a blank in the middle: 4444 444k
Show all output here on this page.
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 | class Main {
static void main(String[] args) {
String[] tests = ["", " ", "2", "333", ".55", "tttTTT", "4444 444k"]
for (String s : tests) {
analyze(s)
}
}
static void analyze(String s) {
println("Examining [$s] which has a length of ${s.length()}")
if (s.length() > 1) {
char firstChar = s.charAt(0)
int lastIndex = s.lastIndexOf(firstChar as String)
if (lastIndex != 0) {
println("\tNot all characters in the string are the same.")
println("\t'$firstChar' (0x${Integer.toHexString(firstChar as Integer)}) is different at position $lastIndex")
return
}
}
println("\tAll characters in the string are the same.")
}
} |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a round table with five individual seats. For eating each philosopher needs two forks (the resources). There are five forks on the table, one left and one right of each seat. When a philosopher cannot grab both forks it sits and waits. Eating takes random time, then the philosopher puts the forks down and leaves the dining room. After spending some random time thinking about the nature of the universe, he again becomes hungry, and the circle repeats itself.
It can be observed that a straightforward solution, when forks are implemented by semaphores, is exposed to deadlock. There exist two deadlock states when all five philosophers are sitting at the table holding one fork each. One deadlock state is when each philosopher has grabbed the fork left of him, and another is when each has the fork on his right.
There are many solutions of the problem, program at least one, and explain how the deadlock is prevented.
| #Nim | Nim | import threadpool, locks, math, os, random
# to call randomize() as a seed, need to import random module
randomize()
type Philosopher = ref object
name: string
food: string
forkLeft, forkRight: int
const
n = 5
names = ["Aristotle", "Kant", "Spinoza", "Marx", "Russell"]
foods = [" rat poison", " cockroaches", " dog food", " lemon-curd toast", " baked worms"]
var
forks: array[n, Lock]
phils: array[n, Philosopher]
threads: array[n, Thread[Philosopher]]
proc run(p: Philosopher) {.thread.} =
# random deprecated, use rand(x .. y)
sleep rand(1..10) * 500
echo p.name, " is hungry."
acquire forks[min(p.forkLeft, p.forkRight)]
sleep rand(1..5) * 500
acquire forks[max(p.forkLeft, p.forkRight)]
echo p.name, " starts eating", p.food, "."
sleep rand(1..10) * 500
echo p.name, " finishes eating", p.food, " and leaves to think."
release forks[p.forkLeft]
release forks[p.forkRight]
for i in 0..<n:
initLock forks[i]
phils[i] = Philosopher(
name: names[i],
food: foods[rand(0 .. n) mod n],
forkLeft: i,
forkRight: (i + 1) mod n
)
createThread(threads[i], run, phils[i])
joinThreads(threads) |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | DiscordianDate[y_, m_, d_] := Module[{year = ToString[y + 1166], month = m, day = d},
DMONTHS = {"Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath"};
DDAYS = {"Sweetmorn", "Boomtime", "Pungenday", "Prickle-Prickle", "Setting Orange"};
DayOfYear = DateDifference[{y} ,{y, m, d}] + 1;
LeapYearQ = (Mod[#, 4]== 0 && (Mod[#, 100] != 0 || Mod[#, 400] == 0))&@ y;
If [ LeapYearQ && month == 2 && day == 29,
Print["Today is St. Tib's Day, YOLD ", ]
,
If [ LeapYearQ && DayOfYear >= 60, DayOfYear -= 1 ];
{season, dday} = {Quotient[DayOfYear, 73], Mod[DayOfYear, 73]};
Print["Today is ", DDAYS[[Mod[dday,4] + 1]],", ",DMONTHS[[season+1]]," ",dday,", YOLD ",year]
];
] |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path problem for a graph with non-negative edge path costs, producing a shortest path tree.
This algorithm is often used in routing and as a subroutine in other graph algorithms.
For a given source vertex (node) in the graph, the algorithm finds the path with lowest cost (i.e. the shortest path) between that vertex and every other vertex.
For instance
If the vertices of the graph represent cities and edge path costs represent driving distances between pairs of cities connected by a direct road, Dijkstra's algorithm can be used to find the shortest route between one city and all other cities.
As a result, the shortest path first is widely used in network routing protocols, most notably:
IS-IS (Intermediate System to Intermediate System) and
OSPF (Open Shortest Path First).
Important note
The inputs to Dijkstra's algorithm are a directed and weighted graph consisting of 2 or more nodes, generally represented by:
an adjacency matrix or list, and
a start node.
A destination node is not specified.
The output is a set of edges depicting the shortest path to each destination node.
An example, starting with
a──►b, cost=7, lastNode=a
a──►c, cost=9, lastNode=a
a──►d, cost=NA, lastNode=a
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►b so a──►b is added to the output.
There is a connection from b──►d so the input is updated to:
a──►c, cost=9, lastNode=a
a──►d, cost=22, lastNode=b
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►c so a──►c is added to the output.
Paths to d and f are cheaper via c so the input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
a──►f, cost=11, lastNode=c
The lowest cost is a──►f so c──►f is added to the output.
The input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
The lowest cost is a──►d so c──►d is added to the output.
There is a connection from d──►e so the input is updated to:
a──►e, cost=26, lastNode=d
Which just leaves adding d──►e to the output.
The output should now be:
[ d──►e
c──►d
c──►f
a──►c
a──►b ]
Task
Implement a version of Dijkstra's algorithm that outputs a set of edges depicting the shortest path to each reachable node from an origin.
Run your program with the following directed graph starting at node a.
Write a program which interprets the output from the above and use it to output the shortest path from node a to nodes e and f.
Vertices
Number
Name
1
a
2
b
3
c
4
d
5
e
6
f
Edges
Start
End
Cost
a
b
7
a
c
9
a
f
14
b
c
10
b
d
15
c
d
11
c
f
2
d
e
6
e
f
9
You can use numbers or names to identify vertices in your program.
See also
Dijkstra's Algorithm vs. A* Search vs. Concurrent Dijkstra's Algorithm (youtube)
| #OCaml | OCaml | let list_vertices graph =
List.fold_left (fun acc ((a, b), _) ->
let acc = if List.mem b acc then acc else b::acc in
let acc = if List.mem a acc then acc else a::acc in
acc
) [] graph
let neighbors v =
List.fold_left (fun acc ((a, b), d) ->
if a = v then (b, d)::acc else acc
) []
let remove_from v lst =
let rec aux acc = function [] -> failwith "remove_from"
| x::xs -> if x = v then List.rev_append acc xs else aux (x::acc) xs
in aux [] lst
let with_smallest_distance q dist =
match q with
| [] -> assert false
| x::xs ->
let rec aux distance v = function
| x::xs ->
let d = Hashtbl.find dist x in
if d < distance
then aux d x xs
else aux distance v xs
| [] -> (v, distance)
in
aux (Hashtbl.find dist x) x xs
let dijkstra max_val zero add graph source target =
let vertices = list_vertices graph in
let dist_between u v =
try List.assoc (u, v) graph
with _ -> zero
in
let dist = Hashtbl.create 1 in
let previous = Hashtbl.create 1 in
List.iter (fun v -> (* initializations *)
Hashtbl.add dist v max_val (* unknown distance function from source to v *)
) vertices;
Hashtbl.replace dist source zero; (* distance from source to source *)
let rec loop = function [] -> ()
| q ->
let u, dist_u =
with_smallest_distance q dist in (* vertex in q with smallest distance in dist *)
if dist_u = max_val then
failwith "vertices inaccessible"; (* all remaining vertices are inaccessible from source *)
if u = target then () else begin
let q = remove_from u q in
List.iter (fun (v, d) ->
if List.mem v q then begin
let alt = add dist_u (dist_between u v) in
let dist_v = Hashtbl.find dist v in
if alt < dist_v then begin (* relax (u,v,a) *)
Hashtbl.replace dist v alt;
Hashtbl.replace previous v u; (* previous node in optimal path from source *)
end
end
) (neighbors u graph);
loop q
end
in
loop vertices;
let s = ref [] in
let u = ref target in
while Hashtbl.mem previous !u do
s := !u :: !s;
u := Hashtbl.find previous !u
done;
(source :: !s)
let () =
let graph =
[ ("a", "b"), 7;
("a", "c"), 9;
("a", "f"), 14;
("b", "c"), 10;
("b", "d"), 15;
("c", "d"), 11;
("c", "f"), 2;
("d", "e"), 6;
("e", "f"), 9; ]
in
let p = dijkstra max_int 0 (+) graph "a" "e" in
print_endline (String.concat " -> " p) |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displaystyle X}
has only one digit.
The additive persistence is the number of summations required to obtain the single digit.
The task is to calculate the additive persistence and the digital root of a number, e.g.:
627615
{\displaystyle 627615}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
39390
{\displaystyle 39390}
has additive persistence
2
{\displaystyle 2}
and digital root of
6
{\displaystyle 6}
;
588225
{\displaystyle 588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
3
{\displaystyle 3}
;
393900588225
{\displaystyle 393900588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
The digital root may be calculated in bases other than 10.
See
Casting out nines for this wiki's use of this procedure.
Digital root/Multiplicative digital root
Sum digits of an integer
Digital root sequence on OEIS
Additive persistence sequence on OEIS
Iterated digits squaring
| #Huginn | Huginn | main( argv_ ) {
if ( size( argv_ ) < 2 ) {
throw Exception( "usage: digital-root {NUM}" );
}
n = argv_[1];
if ( ( size( n ) == 0 ) || ( n.find_other_than( "0123456789" ) >= 0 ) ) {
throw Exception( "{} is not a number".format( n ) );
}
shift = integer( '0' ) + 1;
acc = 0;
for ( d : n ) {
acc = 1 + ( acc + integer( d ) - shift ) % 9;
}
print( "{}\n".format( acc ) );
return ( 0 );
} |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displaystyle X}
has only one digit.
The additive persistence is the number of summations required to obtain the single digit.
The task is to calculate the additive persistence and the digital root of a number, e.g.:
627615
{\displaystyle 627615}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
39390
{\displaystyle 39390}
has additive persistence
2
{\displaystyle 2}
and digital root of
6
{\displaystyle 6}
;
588225
{\displaystyle 588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
3
{\displaystyle 3}
;
393900588225
{\displaystyle 393900588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
The digital root may be calculated in bases other than 10.
See
Casting out nines for this wiki's use of this procedure.
Digital root/Multiplicative digital root
Sum digits of an integer
Digital root sequence on OEIS
Additive persistence sequence on OEIS
Iterated digits squaring
| #Icon_and_Unicon | Icon and Unicon | procedure main(A)
every m := n := integer(!A) do {
ap := 0
while (*n > 1) do (ap +:= 1, n := sumdigits(n))
write(m," has additive persistence of ",ap," and digital root of ",n)
}
end
procedure sumdigits(n)
s := 0
n ? while s +:= move(1)
return s
end |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
{\displaystyle 0}
.
While
m
{\displaystyle m}
has more than one digit:
Find a replacement
m
{\displaystyle m}
as the multiplication of the digits of the current value of
m
{\displaystyle m}
.
Increment
i
{\displaystyle i}
.
Return
i
{\displaystyle i}
(= MP) and
m
{\displaystyle m}
(= MDR)
Task
Tabulate the MP and MDR of the numbers 123321, 7739, 893, 899998
Tabulate MDR versus the first five numbers having that MDR, something like:
MDR: [n0..n4]
=== ========
0: [0, 10, 20, 25, 30]
1: [1, 11, 111, 1111, 11111]
2: [2, 12, 21, 26, 34]
3: [3, 13, 31, 113, 131]
4: [4, 14, 22, 27, 39]
5: [5, 15, 35, 51, 53]
6: [6, 16, 23, 28, 32]
7: [7, 17, 71, 117, 171]
8: [8, 18, 24, 29, 36]
9: [9, 19, 33, 91, 119]
Show all output on this page.
Similar
The Product of decimal digits of n page was redirected here, and had the following description
Find the product of the decimal digits of a positive integer n, where n <= 100
The three existing entries for Phix, REXX, and Ring have been moved here, under ===Similar=== headings, feel free to match or ignore them.
References
Multiplicative Digital Root on Wolfram Mathworld.
Multiplicative digital root on The On-Line Encyclopedia of Integer Sequences.
What's special about 277777788888899? - Numberphile video
| #Scheme | Scheme | ; Convert an integer into a list of its digits.
(define integer->list
(lambda (integer)
(let loop ((list '()) (int integer))
(if (< int 10)
(cons int list)
(loop (cons (remainder int 10) list) (quotient int 10))))))
; Return the product of the digits of an integer.
(define integer-product-digits
(lambda (integer)
(fold-left * 1 (integer->list integer))))
; Compute the multiplicative digital root and multiplicative persistence of an integer.
; Return as a cons of (mdr . mp).
(define mdr-mp
(lambda (integer)
(let loop ((int integer) (cnt 0))
(if (< int 10)
(cons int cnt)
(loop (integer-product-digits int) (1+ cnt))))))
; Emit a table of integer, multiplicative digital root, and multiplicative persistence
; for the example integers given. Example list ends with sequence A003001 from OEIS.
(printf "~16@a ~6@a ~6@a~%" "Integer" "Root" "Pers.")
(printf "~16@a ~6@a ~6@a~%" "===============" "======" "======")
(let rowloop ((intlist '(123321 7739 893 899998
0 10 25 39 77 679 6788 68889 2677889 26888999 3778888999 277777788888899)))
(when (pair? intlist)
(let* ((int (car intlist))
(mm (mdr-mp int)))
(printf "~16@a ~6@a ~6@a~%" int (car mm) (cdr mm))
(rowloop (cdr intlist)))))
; Emit a table of multiplicative digital root versus the first five integers having that MDR.
(newline)
(printf "~5@a ~a~%" "Root" "First five integers with that root")
(printf "~5@a ~a~%" "====" "==================================")
(let ((mdrslsts (make-vector 10 '())))
(do ((integer 0 (1+ integer)))
((>= (fold-left min 5 (vector->list (vector-map length mdrslsts))) 5))
(let ((mdr (car (mdr-mp integer))))
(when (< (length (vector-ref mdrslsts mdr)) 5)
(vector-set! mdrslsts mdr (append (vector-ref mdrslsts mdr) (list integer))))))
(do ((mdr 0 (1+ mdr)))
((>= mdr 10))
(printf "~5@a" mdr)
(for-each (lambda (int) (printf "~7@a" int)) (vector-ref mdrslsts mdr))
(newline))) |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of expression are valued.
Examples may be be split into "setup", "problem statement", and "output" sections where the ease and naturalness of stating the problem and getting an answer, as well as the ease and flexibility of modifying the problem are the primary concerns.
Example output should be shown here, as well as any comments on the examples flexibility.
The problem
Baker, Cooper, Fletcher, Miller, and Smith live on different floors of an apartment house that contains only five floors.
Baker does not live on the top floor.
Cooper does not live on the bottom floor.
Fletcher does not live on either the top or the bottom floor.
Miller lives on a higher floor than does Cooper.
Smith does not live on a floor adjacent to Fletcher's.
Fletcher does not live on a floor adjacent to Cooper's.
Where does everyone live?
| #Phix | Phix | with javascript_semantics
enum Baker, Cooper, Fletcher, Miller, Smith
constant names={"Baker","Cooper","Fletcher","Miller","Smith"}
procedure test(sequence flats)
if flats[Baker]!=5
and flats[Cooper]!=1
and not find(flats[Fletcher],{1,5})
and flats[Miller]>flats[Cooper]
and abs(flats[Smith]-flats[Fletcher])!=1
and abs(flats[Fletcher]-flats[Cooper])!=1 then
for i=1 to 5 do
?{names[i],flats[i]}
end for
end if
end procedure
for i=1 to factorial(5) do
test(permute(i,tagset(5)))
end for
|
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot product of two vectors directly:
each vector must be the same length
multiply corresponding terms from each vector
sum the products (to produce the answer)
Related task
Vector products
| #Hoon | Hoon | |= [a=(list @sd) b=(list @sd)]
=| sum=@sd
|-
?: |(?=(~ a) ?=(~ b)) sum
$(a t.a, b t.b, sum (sum:si sum (pro:si i.a i.b))) |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot product of two vectors directly:
each vector must be the same length
multiply corresponding terms from each vector
sum the products (to produce the answer)
Related task
Vector products
| #Hy | Hy | (defn dotp [a b]
(assert (= (len a) (len b)))
(sum (genexpr (* aterm bterm)
[(, aterm bterm) (zip a b)])))
(assert (= 3 (dotp [1 3 -5] [4 -2 -1]))) |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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
| #Julia | Julia | const teststringpairs = [
("", ' '),
(""""If I were two-faced, would I be wearing this one?" --- Abraham Lincoln """, '-'),
("..1111111111111111111111111111111111111111111111111111111111111117777888", '7'),
("""I never give 'em hell, I just tell the truth, and they think it's hell. """, '.'),
(" --- Harry S Truman ", ' '),
(" --- Harry S Truman ", '-'),
(" --- Harry S Truman ", 'r')]
function squeezed(s, c)
t = isempty(s) ? "" : s[1:1]
for x in s[2:end]
if x != t[end] || x != c
t *= x
end
end
t
end
for (s, c) in teststringpairs
n, t = length(s), squeezed(s, c)
println("«««$s»»» (length $n)\n",
s == t ? "is not squeezed, so remains" : "squeezes to",
":\n«««$t»»» (length $(length(t))).\n")
end
|
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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
| #Kotlin | Kotlin | fun main() {
val testStrings = arrayOf(
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I never give 'em hell, I just tell the truth, and they think it's hell. ",
" --- Harry S Truman ",
"122333444455555666666777777788888888999999999",
"The better the 4-wheel drive, the further you'll be from help when ya get stuck!",
"headmistressship")
val testChar = arrayOf(
" ",
"-",
"7",
".",
" -r",
"5",
"e",
"s")
for (testNum in testStrings.indices) {
val s = testStrings[testNum]
for (c in testChar[testNum].toCharArray()) {
val result = squeeze(s, c)
System.out.printf("use: '%c'%nold: %2d >>>%s<<<%nnew: %2d >>>%s<<<%n%n", c, s.length, s, result.length, result)
}
}
}
private fun squeeze(input: String, include: Char): String {
val sb = StringBuilder()
for (i in input.indices) {
if (i == 0 || input[i - 1] != input[i] || input[i - 1] == input[i] && input[i] != include) {
sb.append(input[i])
}
}
return sb.toString()
} |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to improve performance. In each case the experiment begins with the funnel positioned directly over the target.
Rule 1: The funnel remains directly above the target.
Rule 2: Adjust the funnel position by shifting the target to compensate after each drop. E.g. If the last drop missed 1 cm east, move the funnel 1 cm to the west of its current position.
Rule 3: As rule 2, but first move the funnel back over the target, before making the adjustment. E.g. If the funnel is 2 cm north, and the marble lands 3 cm north, move the funnel 3 cm south of the target.
Rule 4: The funnel is moved directly over the last place a marble landed.
Apply the four rules to the set of 50 pseudorandom displacements provided (e.g in the Racket solution) for the dxs and dys. Output: calculate the mean and standard-deviations of the resulting x and y values for each rule.
Note that rules 2, 3, and 4 give successively worse results. Trying to deterministically compensate for a random process is counter-productive, but -- according to Deming -- quite a popular pastime: see the Further Information, below for examples.
Stretch goal 1: Generate fresh pseudorandom data. The radial displacement of the drop from the funnel position is given by a Gaussian distribution (standard deviation is 1.0) and the angle of displacement is uniformly distributed.
Stretch goal 2: Show scatter plots of all four results.
Further information
Further explanation and interpretation
Video demonstration of the funnel experiment at the Mayo Clinic. | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | dxs = {-0.533, 0.27, 0.859, -0.043, -0.205, -0.127, -0.071, 0.275,
1.251, -0.231, -0.401, 0.269, 0.491, 0.951, 1.15, 0.001, -0.382,
0.161, 0.915, 2.08, -2.337, 0.034, -0.126, 0.014, 0.709,
0.129, -1.093, -0.483, -1.193, 0.02, -0.051, 0.047, -0.095, 0.695,
0.34, -0.182, 0.287, 0.213, -0.423, -0.021, -0.134, 1.798,
0.021, -1.099, -0.361, 1.636, -1.134, 1.315, 0.201, 0.034,
0.097, -0.17, 0.054, -0.553, -0.024, -0.181, -0.7, -0.361, -0.789,
0.279, -0.174, -0.009, -0.323, -0.658, 0.348, -0.528, 0.881,
0.021, -0.853, 0.157, 0.648, 1.774, -1.043, 0.051, 0.021,
0.247, -0.31, 0.171, 0., 0.106, 0.024, -0.386, 0.962,
0.765, -0.125, -0.289, 0.521, 0.017,
0.281, -0.749, -0.149, -2.436, -0.909, 0.394, -0.113, -0.598,
0.443, -0.521, -0.799, 0.087};
dys = {0.136, 0.717, 0.459, -0.225, 1.392, 0.385, 0.121, -0.395,
0.49, -0.682, -0.065, 0.242, -0.288, 0.658, 0.459, 0., 0.426,
0.205, -0.765, -2.188, -0.742, -0.01, 0.089, 0.208, 0.585,
0.633, -0.444, -0.351, -1.087, 0.199, 0.701, 0.096, -0.025, -0.868,
1.051, 0.157, 0.216, 0.162, 0.249, -0.007, 0.009, 0.508, -0.79,
0.723, 0.881, -0.508, 0.393, -0.226, 0.71, 0.038, -0.217, 0.831,
0.48, 0.407, 0.447, -0.295, 1.126, 0.38, 0.549, -0.445, -0.046,
0.428, -0.074, 0.217, -0.822, 0.491, 1.347, -0.141, 1.23, -0.044,
0.079, 0.219, 0.698, 0.275, 0.056, 0.031, 0.421, 0.064, 0.721,
0.104, -0.729, 0.65, -1.103, 0.154, -1.72, 0.051, -0.385, 0.477,
1.537, -0.901, 0.939, -0.411, 0.341, -0.411, 0.106,
0.224, -0.947, -1.424, -0.542, -1.032};
(*Mathematica's StandardDeviation function computes the unbiased standard deviation. The solutions seem to be using the biased standard deviation, so I'll create a custom function for that.*)
BiasedStandardDeviation[data_] :=
With[
{mean = Mean@data},
Sqrt[Total[(# - mean)^2 & /@ data]/Length[data]]
]
(*Mathematica's FoldPair functionality will work well with this if we provide a properly defined function to fold with.*)
DemingRule[1][funnelPosition_, diff_] := {funnelPosition + diff, 0};
DemingRule[2][funnelPosition_, diff_] := {funnelPosition + diff, -diff};
DemingRule[3][funnelPosition_, diff_] := {funnelPosition + diff, -funnelPosition - diff};
DemingRule[4][funnelPosition_, diff_] := {funnelPosition + diff, funnelPosition + diff};
(*The core implementation.*)
MarblePositions[rule_][diffs_] := FoldPairList[DemingRule[rule], 0, diffs];
(*This is to help format the output.*)
Results[rule_, diffData_] :=
With[
{positions = MarblePositions[rule][diffData]},
StringForm["Rule `1`\nmean: `2`\nstd dev: `3`", rule, Mean[positions], BiasedStandardDeviation[positions]]
];
TableForm[Results[#, Transpose[{dxs, dys}]] & /@ Range[4], TableSpacing -> 5] |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to improve performance. In each case the experiment begins with the funnel positioned directly over the target.
Rule 1: The funnel remains directly above the target.
Rule 2: Adjust the funnel position by shifting the target to compensate after each drop. E.g. If the last drop missed 1 cm east, move the funnel 1 cm to the west of its current position.
Rule 3: As rule 2, but first move the funnel back over the target, before making the adjustment. E.g. If the funnel is 2 cm north, and the marble lands 3 cm north, move the funnel 3 cm south of the target.
Rule 4: The funnel is moved directly over the last place a marble landed.
Apply the four rules to the set of 50 pseudorandom displacements provided (e.g in the Racket solution) for the dxs and dys. Output: calculate the mean and standard-deviations of the resulting x and y values for each rule.
Note that rules 2, 3, and 4 give successively worse results. Trying to deterministically compensate for a random process is counter-productive, but -- according to Deming -- quite a popular pastime: see the Further Information, below for examples.
Stretch goal 1: Generate fresh pseudorandom data. The radial displacement of the drop from the funnel position is given by a Gaussian distribution (standard deviation is 1.0) and the angle of displacement is uniformly distributed.
Stretch goal 2: Show scatter plots of all four results.
Further information
Further explanation and interpretation
Video demonstration of the funnel experiment at the Mayo Clinic. | #Stretch_1 | Stretch 1 |
RadiusDistribution = NormalDistribution[0, 1];
AngleDistribution = UniformDistribution[{0, Pi}];
(*Mathematica has built in transformation functions, but this seems clearer given the way the instructions were written.*)
ToCartesian[{r_, a_}] := ToCartesian[{Abs@r, a - Pi}] /; Negative[r];
ToCartesian[{r_, a_}] := FromPolarCoordinates[{r, a}];
newData =
ToCartesian /@
Transpose[{RandomVariate[RadiusDistribution, 100],
RandomVariate[AngleDistribution, 100]}];
TableForm[Results[#, newData] & /@ Range[4], TableSpacing -> 5]
|
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and must add up to 12.
The Chief of the Police doesn't like odd numbers and wants to have an even number for his department.
Task
Write a computer program which outputs all valid combinations.
Possible output (for the 1st and 14th solutions):
--police-- --sanitation-- --fire--
2 3 7
6 5 1
| #AppleScript | AppleScript | on run
script
on |λ|(x)
script
on |λ|(y)
script
on |λ|(z)
if y ≠ z and 1 ≤ z and z ≤ 7 then
{{x, y, z} as string}
else
{}
end if
end |λ|
end script
concatMap(result, {12 - (x + y)}) --Z
end |λ|
end script
concatMap(result, {1, 2, 3, 4, 5, 6, 7}) --Y
end |λ|
end script
unlines(concatMap(result, {2, 4, 6})) --X
end run
-- GENERIC FUNCTIONS ----------------------------------------------------------
-- concatMap :: (a -> [b]) -> [a] -> [b]
on concatMap(f, xs)
set lst to {}
set lng to length of xs
tell mReturn(f)
repeat with i from 1 to lng
set lst to (lst & |λ|(contents of item i of xs, i, xs))
end repeat
end tell
return lst
end concatMap
-- intercalate :: Text -> [Text] -> Text
on intercalate(strText, lstText)
set {dlm, my text item delimiters} to {my text item delimiters, strText}
set strJoined to lstText as text
set my text item delimiters to dlm
return strJoined
end intercalate
-- Lift 2nd class handler function into 1st class script wrapper
-- mReturn :: Handler -> Script
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn
-- unlines :: [String] -> String
on unlines(xs)
intercalate(linefeed, xs)
end unlines |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects responsibilities:
Delegator:
Keep an optional delegate instance.
Implement "operation" method, returning the delegate "thing" if the delegate respond to "thing", or the string "default implementation".
Delegate:
Implement "thing" and return the string "delegate implementation"
Show how objects are created and used. First, without a delegate, then with a delegate that does not implement "thing", and last with a delegate that implements "thing".
| #Common_Lisp | Common Lisp | (defgeneric thing (object)
(:documentation "Thing the object."))
(defmethod thing (object)
"default implementation")
(defclass delegator ()
((delegate
:initarg :delegate
:reader delegator-delegate)))
(defmethod thing ((delegator delegator))
"If delegator has a delegate, invoke thing on the delegate,
otherwise return \"no delegate\"."
(if (slot-boundp delegator 'delegate)
(thing (delegator-delegate delegator))
"no delegate"))
(defclass delegate () ())
(defmethod thing ((delegate delegate))
"delegate implementation")
(let ((d1 (make-instance 'delegator))
(d2 (make-instance 'delegator :delegate nil))
(d3 (make-instance 'delegator :delegate (make-instance 'delegate))))
(assert (string= "no delegate" (thing d1)))
(assert (string= "default implementation" (thing d2)))
(assert (string= "delegate implementation" (thing d3)))) |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects responsibilities:
Delegator:
Keep an optional delegate instance.
Implement "operation" method, returning the delegate "thing" if the delegate respond to "thing", or the string "default implementation".
Delegate:
Implement "thing" and return the string "delegate implementation"
Show how objects are created and used. First, without a delegate, then with a delegate that does not implement "thing", and last with a delegate that implements "thing".
| #D | D | class Delegator {
string delegate() hasDelegate;
string operation() {
if (hasDelegate is null)
return "Default implementation";
return hasDelegate();
}
typeof(this) setDg(string delegate() dg) {
hasDelegate = dg;
return this;
}
}
void main() {
import std.stdio;
auto dr = new Delegator;
string delegate() thing = () => "Delegate implementation";
writeln(dr.operation());
writeln(dr.operation());
writeln(dr.setDg(thing).operation());
} |
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)
(0,0),(5,0),(2.5,5) and (0,4),(2.5,-1),(5,4)
(0,0),(1,1),(0,2) and (2,1),(3,0),(3,2)
(0,0),(1,1),(0,2) and (2,1),(3,-2),(3,4)
Optionally, see what the result is when only a single corner is in contact (there is no definitive correct answer):
(0,0),(1,0),(0,1) and (1,0),(2,0),(1,1)
| #Haskell | Haskell | isOverlapping :: Triangle Double -> Triangle Double -> Bool
isOverlapping t1 t2 = vertexInside || midLineInside
where
vertexInside =
any (isInside t1) (vertices t2) ||
any (isInside t2) (vertices t1)
isInside t = (Outside /=) . overlapping t
midLineInside =
any (\p -> isInside t1 p && isInside t2 p) midPoints
midPoints =
[ intersections l1 l2 | l1 <- midLines t1
, l2 <- midLines t2 ]
intersections (a1,b1,c1) (a2,b2,c2) =
( -(-b2*c1+b1*c2)/(a2*b1-a1*b2)
, -(a2*c1-a1*c2)/(a2*b1-a1*b2) )
midLines (Triangle a b c) =
[line a b c, line b c a, line c a b]
line (x,y) (ax, ay) (bx, by) =
(ay+by-2*y, -ax-bx+2*x, -ay*x-by*x+ax*y+bx*y)
test = map (uncurry isOverlapping)
[ (Triangle (0,0) (5,0) (0,5), Triangle (0,0) (5,0) (0,6))
, (Triangle (0,0) (0,5) (5,0), Triangle (0,0) (0,5) (5,0))
, (Triangle (0,0) (5,0) (0,5), Triangle (-10,0) (-5,0) (-1,6))
, (Triangle (0,0) (5,0) (2.5,5), Triangle (0,4) (2.5,-1) (5,4))
, (Triangle (0,0) (1,1) (0,2), Triangle (2,1) (3,0) (3,2))
, (Triangle (0,0) (1,1) (0,2), Triangle (2,1) (3,-2) (3,4))
, (Triangle (0,0) (1,0) (0,1), Triangle (1,0) (2,0) (1,1))] |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #C | C | #include <stdio.h>
int main() {
remove("input.txt");
remove("/input.txt");
remove("docs");
remove("/docs");
return 0;
} |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #C.23 | C# | using System;
using System.IO;
namespace RosettaCode {
class Program {
static void Main() {
try {
File.Delete("input.txt");
Directory.Delete("docs");
File.Delete(@"\input.txt");
Directory.Delete(@"\docs");
} catch (Exception exception) {
Console.WriteLine(exception.Message);
}
}
}
} |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
perm
(
A
)
=
∑
σ
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \operatorname {perm} (A)=\sum _{\sigma }\prod _{i=1}^{n}M_{i,\sigma _{i}}}
In both cases the sum is over the permutations
σ
{\displaystyle \sigma }
of the permutations of 1, 2, ..., n. (A permutation's sign is 1 if there are an even number of inversions and -1 otherwise; see parity of a permutation.)
More efficient algorithms for the determinant are known: LU decomposition, see for example wp:LU decomposition#Computing the determinant. Efficient methods for calculating the permanent are not known.
Related task
Permutations by swapping
| #Haskell | Haskell | sPermutations :: [a] -> [([a], Int)]
sPermutations = flip zip (cycle [1, -1]) . foldl aux [[]]
where
aux items x = do
(f, item) <- zip (cycle [reverse, id]) items
f (insertEv x item)
insertEv x [] = [[x]]
insertEv x l@(y:ys) = (x : l) : ((y :) <$>) (insertEv x ys)
elemPos :: [[a]] -> Int -> Int -> a
elemPos ms i j = (ms !! i) !! j
prod
:: Num a
=> ([[a]] -> Int -> Int -> a) -> [[a]] -> [Int] -> a
prod f ms = product . zipWith (f ms) [0 ..]
sDeterminant
:: Num a
=> ([[a]] -> Int -> Int -> a) -> [[a]] -> [([Int], Int)] -> a
sDeterminant f ms = sum . fmap (\(is, s) -> fromIntegral s * prod f ms is)
determinant
:: Num a
=> [[a]] -> a
determinant ms =
sDeterminant elemPos ms . sPermutations $ [0 .. pred . length $ ms]
permanent
:: Num a
=> [[a]] -> a
permanent ms =
sum . fmap (prod elemPos ms . fst) . sPermutations $ [0 .. pred . length $ ms]
-- TEST -----------------------------------------------------------------------
result
:: (Num a, Show a)
=> [[a]] -> String
result ms =
unlines
[ "Matrix:"
, unlines (show <$> ms)
, "Determinant:"
, show (determinant ms)
, "Permanent:"
, show (permanent ms)
]
main :: IO ()
main =
mapM_
(putStrLn . result)
[ [[5]]
, [[1, 0, 0], [0, 1, 0], [0, 0, 1]]
, [[0, 0, 1], [0, 1, 0], [1, 0, 0]]
, [[4, 3], [2, 5]]
, [[2, 5], [4, 3]]
, [[4, 4], [2, 2]]
] |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #E | E | def divide(numerator, denominator) {
def floatQuotient := numerator / denominator
if (floatQuotient.isNaN() || floatQuotient.isInfinite()) {
return ["zero denominator"]
} else {
return ["ok", floatQuotient]
}
} |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #ECL | ECL |
DBZ(REAL8 Dividend,INTEGER8 Divisor) := Quotient/Divisor;
#option ('divideByZero', 'zero');
DBZ(10,0); //returns 0.0
|
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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
| #CFScript | CFScript | isNumeric(42) |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
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 numeric? [s]
(if-let [s (seq s)]
(let [s (if (= (first s) \-) (next s) s)
s (drop-while #(Character/isDigit %) s)
s (if (= (first s) \.) (next s) s)
s (drop-while #(Character/isDigit %) s)]
(empty? s)))) |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as unique
process the strings from left─to─right
if unique, display a message saying such
if not unique, then:
display a message saying such
display what character is duplicated
only the 1st non─unique character need be displayed
display where "both" duplicated characters are in the string
the above messages can be part of a single message
display the hexadecimal value of the duplicated character
Use (at least) these five test values (strings):
a string of length 0 (an empty string)
a string of length 1 which is a single period (.)
a string of length 6 which contains: abcABC
a string of length 7 which contains a blank in the middle: XYZ ZYX
a string of length 36 which doesn't contain the letter "oh":
1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ
Show all output here on this page.
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# |
// Determine if a string has all unique characters. Nigel Galloway: June 9th., 2020
let fN (n:string)=n.ToCharArray()|>Array.mapi(fun n g->(n,g))|>Array.groupBy(fun (_,n)->n)|>Array.filter(fun(_,n)->n.Length>1)
let allUnique n=match fN n with
g when g.Length=0->printfn "All charcters in <<<%s>>> (length %d) are unique" n n.Length
|g->Array.iter(fun(n,g)->printf "%A is repeated at positions" n; Array.iter(fun(n,_)->printf " %d" n)g;printf " ")g
printfn "in <<<%s>>> (length %d)" n n.Length
allUnique ""
allUnique "."
allUnique "abcABC"
allUnique "XYZ ZYX"
allUnique "1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ"
|
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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
| #Julia | Julia | const teststrings = [
"",
""""If I were two-faced, would I be wearing this one?" --- Abraham Lincoln """,
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"""I never give 'em hell, I just tell the truth, and they think it's hell. """,
" --- Harry S Truman "]
function collapse(s)
len = length(s)
if len < 2
return s, len, s, len
end
result = last = s[1]
for c in s[2:end]
if c != last
last = c
result *= c
end
end
return s, len, result, length(result)
end
function testcollapse(arr)
for s in arr
(s1, len1, s2, len2) = collapse(s)
println("«««$s1»»» (length $len1)\n collapses to:\n«««$s2»»» (length $len2).\n")
end
end
testcollapse(teststrings)
|
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediately repeated character is any character that is immediately followed by an
identical character (or characters). Another word choice could've been duplicated character, but that
might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around November 2019) PL/I BIF: collapse.}
Examples
In the following character string:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd t, e, and l are repeated characters, indicated
by underscores (above), even though they (those characters) appear elsewhere in the character string.
So, after collapsing the string, the result would be:
The beter the 4-whel drive, the further you'l be from help when ya get stuck!
Another example:
In the following character string:
headmistressship
The "collapsed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to
locate repeated characters and collapse (delete) them from the character
string. The character string can be processed from either direction.
Show all output here, on this page:
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
string
number
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║
5 ║ --- Harry S Truman ║ ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝
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
| #Kotlin | Kotlin | fun collapse(s: String): String {
val cs = StringBuilder()
var last: Char = 0.toChar()
for (c in s) {
if (c != last) {
cs.append(c)
last = c
}
}
return cs.toString()
}
fun main() {
val strings = arrayOf(
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I never give 'em hell, I just tell the truth, and they think it's hell. ",
" --- Harry S Truman ",
"The better the 4-wheel drive, the further you'll be from help when ya get stuck!",
"headmistressship",
"aardvark"
)
for (s in strings) {
val c = collapse(s)
println("original : length = ${s.length}, string = «««$s»»»")
println("collapsed : length = ${c.length}, string = «««$c»»»")
println()
}
} |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the strings are being examined)
a zero─length (empty) string shall be considered as all the same character(s)
process the strings from left─to─right
if all the same character, display a message saying such
if not all the same character, then:
display a message saying such
display what character is different
only the 1st different character need be displayed
display where the different character is in the string
the above messages can be part of a single message
display the hexadecimal value of the different character
Use (at least) these seven test values (strings):
a string of length 0 (an empty string)
a string of length 3 which contains three blanks
a string of length 1 which contains: 2
a string of length 3 which contains: 333
a string of length 3 which contains: .55
a string of length 6 which contains: tttTTT
a string of length 9 with a blank in the middle: 4444 444k
Show all output here on this page.
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 | import Numeric (showHex)
import Data.List (span)
import Data.Char (ord)
inconsistentChar :: Eq a => [a] -> Maybe (Int, a)
inconsistentChar [] = Nothing
inconsistentChar xs@(x:_) =
let (pre, post) = span (x ==) xs
in if null post
then Nothing
else Just (length pre, head post)
---------------------------TEST----------------------------
samples :: [String]
samples = [" ", "2", "333", ".55", "tttTTT", "4444 444"]
main :: IO ()
main = do
let w = succ . maximum $ length <$> samples
justifyRight n c = (drop . length) <*> (replicate n c ++)
f = (++ "' -> ") . justifyRight w ' ' . ('\'' :)
(putStrLn . unlines) $
(\s ->
maybe
(f s ++ "consistent")
(\(n, c) ->
f s ++
"inconsistent '" ++
c : "' (0x" ++ showHex (ord c) ")" ++ " at char " ++ show (succ n))
(inconsistentChar s)) <$>
samples |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a round table with five individual seats. For eating each philosopher needs two forks (the resources). There are five forks on the table, one left and one right of each seat. When a philosopher cannot grab both forks it sits and waits. Eating takes random time, then the philosopher puts the forks down and leaves the dining room. After spending some random time thinking about the nature of the universe, he again becomes hungry, and the circle repeats itself.
It can be observed that a straightforward solution, when forks are implemented by semaphores, is exposed to deadlock. There exist two deadlock states when all five philosophers are sitting at the table holding one fork each. One deadlock state is when each philosopher has grabbed the fork left of him, and another is when each has the fork on his right.
There are many solutions of the problem, program at least one, and explain how the deadlock is prevented.
| #OxygenBasic | OxygenBasic |
'=========================
class RoundTableWith5Seats
'=========================
% hungry 0
% beingUsed 1
% putDown 0
% empty 0
sys fork[5], plate[5],chair[5],philosopher[5]
sys first
method AddPasta() as sys
function rand() as sys
static seed=0x12345678
mov eax,seed
rol eax,7
mul seed
xor eax,0x5335ABD9
mov seed,eax
return seed
end function
return 4+(rand() and 15)
end method
method dine()
first++ 'PRIORITY DINER
if first>5 then first-=5
for i=1 to 5
kl=first+i-1
kr=first+i
if kl>5 then kl-=5
if kr>5 then kr-=5
if philosopher(kl) = hungry then
if not fork(kl) or fork(kr) = beingUsed then
plate(kl) = AddPasta()
fork(kl)=beingUsed
fork(kr)=beingUsed
end if
end if
'
next
'
for kl=1 to 5
kr=kl+1 : if kr>5 then kr-=5
if plate(kl)
philosopher(kl)+=1 'PHILOSOPHER DINING
--plate(kl)
if plate(kl)=empty
fork(kl)=PutDown
fork(kr)=PutDown
end if
else
if philosopher(kl)>0
--philosopher(kl) 'PHILOSOPHER THINKING
end if
end if
next
'
end method
method show() as string
cr=chr(13)+chr(10) : tab=chr(9)
pr="philos" tab "activity" tab "plate" tab "fork L" tab "fork R" cr cr
for i=1 to 5
j=i+1 : if j>5 then j-=5
if plate(i)=0 then
if philosopher(i)=0 then
act="waiting"
else
act="thinks"
end if
else
act="dining"
end if
'
pr+=i tab act tab plate(i) tab fork(i) tab fork(j) cr
next
return pr
end method
end class
'TEST
'====
RoundTableWith5Seats Sopho
for i=1 to 100
Sopho.dine
next
print Sopho.show
'putfile "s.txt",Sopho.show
'philos action plate fork L fork R
'
'1 waiting 0 0 1
'2 dining 8 1 1
'3 thinks 0 1 1
'4 dining 8 1 1
'5 thinks 0 1 0
|
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Nim | Nim | import times, strformat
const
DiscordianOrigin = -1166
SaintTibsDay = "St. Tib’s Day"
type
Season = enum
sCha = (1, "Chaos"), sDis = "Discord", sCon = "Confusion",
sBur = "Bureaucracy", sAft = "The Aftermath"
ErisianWeekDay = enum
eSwe = "Sweetmorn", eBoo = "Boomtime", ePun = "Pungenday",
ePri = "Prickle-Prickle", eSet = "Setting Orange"
SeasonDayRange = range[1..73]
# Description of a discordian date.
DiscordianDate = object
year: int
yearday: YeardayRange
case isSaintTibsDay: bool
of false:
seasondayZero: int
seasonZero: int
weekday: ErisianWeekDay
else:
nil
#---------------------------------------------------------------------------------------------------
proc toDiscordianDate(gdate: DateTime): DiscordianDate =
## Convert a DateTime to a discordian date.
## All the time fields are ignored.
# Create the object.
result = DiscordianDate(isSaintTibsDay: gdate.isLeapDay)
# The yearday field is unchanged.
result.yearday = gdate.yearday
# The year is simply translated.
result.year = gdate.year - DiscordianOrigin
# For remaining fields, we must take in account leap years.
if not result.isSaintTibsDay:
var yearday = result.yearday
if gdate.year.isLeapYear and result.yearday > 59:
dec yearday
# Now, we have simply to use division and modulo using the corrected yearday.
result.seasonZero = yearday div SeasonDayRange.high
result.seasondayZero = yearday mod SeasonDayRange.high
result.weekday = ErisianWeekDay(yearday mod 5)
#---------------------------------------------------------------------------------------------------
proc `$`(date: DiscordianDate): string =
## Convert a discordian date to a string.
if date.isSaintTibsDay:
result = SaintTibsDay
else:
result = fmt"{date.weekday}, {Season(date.seasonZero + 1)} {date.seasondayZero + 1}"
result &= fmt", {date.year} YOLD"
#---------------------------------------------------------------------------------------------------
proc showDiscordianDate(year, month, day: Natural) =
## Show the discordian date corresponding to a gregorian date.
let gdate = initDateTime(year = year, month = Month(month), monthday = day,
hour = 0, minute = 0, second = 0)
echo gdate.format("YYYY-MM-dd"), ": ", $gdate.toDiscordianDate()
#———————————————————————————————————————————————————————————————————————————————————————————————————
showDiscordianDate(2100, 12, 31)
showDiscordianDate(2012, 02, 28)
showDiscordianDate(2012, 02, 29)
showDiscordianDate(2012, 03, 01)
showDiscordianDate(2010, 07, 22)
showDiscordianDate(2012, 09, 02)
showDiscordianDate(2012, 12, 31) |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path problem for a graph with non-negative edge path costs, producing a shortest path tree.
This algorithm is often used in routing and as a subroutine in other graph algorithms.
For a given source vertex (node) in the graph, the algorithm finds the path with lowest cost (i.e. the shortest path) between that vertex and every other vertex.
For instance
If the vertices of the graph represent cities and edge path costs represent driving distances between pairs of cities connected by a direct road, Dijkstra's algorithm can be used to find the shortest route between one city and all other cities.
As a result, the shortest path first is widely used in network routing protocols, most notably:
IS-IS (Intermediate System to Intermediate System) and
OSPF (Open Shortest Path First).
Important note
The inputs to Dijkstra's algorithm are a directed and weighted graph consisting of 2 or more nodes, generally represented by:
an adjacency matrix or list, and
a start node.
A destination node is not specified.
The output is a set of edges depicting the shortest path to each destination node.
An example, starting with
a──►b, cost=7, lastNode=a
a──►c, cost=9, lastNode=a
a──►d, cost=NA, lastNode=a
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►b so a──►b is added to the output.
There is a connection from b──►d so the input is updated to:
a──►c, cost=9, lastNode=a
a──►d, cost=22, lastNode=b
a──►e, cost=NA, lastNode=a
a──►f, cost=14, lastNode=a
The lowest cost is a──►c so a──►c is added to the output.
Paths to d and f are cheaper via c so the input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
a──►f, cost=11, lastNode=c
The lowest cost is a──►f so c──►f is added to the output.
The input is updated to:
a──►d, cost=20, lastNode=c
a──►e, cost=NA, lastNode=a
The lowest cost is a──►d so c──►d is added to the output.
There is a connection from d──►e so the input is updated to:
a──►e, cost=26, lastNode=d
Which just leaves adding d──►e to the output.
The output should now be:
[ d──►e
c──►d
c──►f
a──►c
a──►b ]
Task
Implement a version of Dijkstra's algorithm that outputs a set of edges depicting the shortest path to each reachable node from an origin.
Run your program with the following directed graph starting at node a.
Write a program which interprets the output from the above and use it to output the shortest path from node a to nodes e and f.
Vertices
Number
Name
1
a
2
b
3
c
4
d
5
e
6
f
Edges
Start
End
Cost
a
b
7
a
c
9
a
f
14
b
c
10
b
d
15
c
d
11
c
f
2
d
e
6
e
f
9
You can use numbers or names to identify vertices in your program.
See also
Dijkstra's Algorithm vs. A* Search vs. Concurrent Dijkstra's Algorithm (youtube)
| #PARI.2FGP | PARI/GP | shortestPath(G, startAt=1)={
my(n=#G[,1],dist=vector(n,i,9e99),prev=dist,Q=2^n-1);
dist[startAt]=0;
while(Q,
my(t=vecmin(vecextract(dist,Q)),u);
if(t==9e99, break);
for(i=1,#v,if(dist[i]==t && bittest(Q,i-1), u=i; break));
Q-=1<<(u-1);
for(i=1,n,
if(!G[u,i],next);
my(alt=dist[u]+G[u,i]);
if (alt < dist[i],
dist[i]=alt;
prev[i]=u;
)
)
);
dist
}; |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displaystyle X}
has only one digit.
The additive persistence is the number of summations required to obtain the single digit.
The task is to calculate the additive persistence and the digital root of a number, e.g.:
627615
{\displaystyle 627615}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
39390
{\displaystyle 39390}
has additive persistence
2
{\displaystyle 2}
and digital root of
6
{\displaystyle 6}
;
588225
{\displaystyle 588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
3
{\displaystyle 3}
;
393900588225
{\displaystyle 393900588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
The digital root may be calculated in bases other than 10.
See
Casting out nines for this wiki's use of this procedure.
Digital root/Multiplicative digital root
Sum digits of an integer
Digital root sequence on OEIS
Additive persistence sequence on OEIS
Iterated digits squaring
| #J | J | digrot=: +/@(#.inv~&10)^:_
addper=: _1 + [: # +/@(#.inv~&10)^:a: |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displaystyle X}
has only one digit.
The additive persistence is the number of summations required to obtain the single digit.
The task is to calculate the additive persistence and the digital root of a number, e.g.:
627615
{\displaystyle 627615}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
39390
{\displaystyle 39390}
has additive persistence
2
{\displaystyle 2}
and digital root of
6
{\displaystyle 6}
;
588225
{\displaystyle 588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
3
{\displaystyle 3}
;
393900588225
{\displaystyle 393900588225}
has additive persistence
2
{\displaystyle 2}
and digital root of
9
{\displaystyle 9}
;
The digital root may be calculated in bases other than 10.
See
Casting out nines for this wiki's use of this procedure.
Digital root/Multiplicative digital root
Sum digits of an integer
Digital root sequence on OEIS
Additive persistence sequence on OEIS
Iterated digits squaring
| #Java | Java | import java.math.BigInteger;
class DigitalRoot
{
public static int[] calcDigitalRoot(String number, int base)
{
BigInteger bi = new BigInteger(number, base);
int additivePersistence = 0;
if (bi.signum() < 0)
bi = bi.negate();
BigInteger biBase = BigInteger.valueOf(base);
while (bi.compareTo(biBase) >= 0)
{
number = bi.toString(base);
bi = BigInteger.ZERO;
for (int i = 0; i < number.length(); i++)
bi = bi.add(new BigInteger(number.substring(i, i + 1), base));
additivePersistence++;
}
return new int[] { additivePersistence, bi.intValue() };
}
public static void main(String[] args)
{
for (String arg : args)
{
int[] results = calcDigitalRoot(arg, 10);
System.out.println(arg + " has additive persistence " + results[0] + " and digital root of " + results[1]);
}
}
} |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
{\displaystyle 0}
.
While
m
{\displaystyle m}
has more than one digit:
Find a replacement
m
{\displaystyle m}
as the multiplication of the digits of the current value of
m
{\displaystyle m}
.
Increment
i
{\displaystyle i}
.
Return
i
{\displaystyle i}
(= MP) and
m
{\displaystyle m}
(= MDR)
Task
Tabulate the MP and MDR of the numbers 123321, 7739, 893, 899998
Tabulate MDR versus the first five numbers having that MDR, something like:
MDR: [n0..n4]
=== ========
0: [0, 10, 20, 25, 30]
1: [1, 11, 111, 1111, 11111]
2: [2, 12, 21, 26, 34]
3: [3, 13, 31, 113, 131]
4: [4, 14, 22, 27, 39]
5: [5, 15, 35, 51, 53]
6: [6, 16, 23, 28, 32]
7: [7, 17, 71, 117, 171]
8: [8, 18, 24, 29, 36]
9: [9, 19, 33, 91, 119]
Show all output on this page.
Similar
The Product of decimal digits of n page was redirected here, and had the following description
Find the product of the decimal digits of a positive integer n, where n <= 100
The three existing entries for Phix, REXX, and Ring have been moved here, under ===Similar=== headings, feel free to match or ignore them.
References
Multiplicative Digital Root on Wolfram Mathworld.
Multiplicative digital root on The On-Line Encyclopedia of Integer Sequences.
What's special about 277777788888899? - Numberphile video
| #Sidef | Sidef | func mdroot(n) {
var (mdr, persist) = (n, 0)
while (mdr >= 10) {
mdr = mdr.digits.prod
++persist
}
[mdr, persist]
}
say "Number: MDR MP\n====== === =="
[123321, 7739, 893, 899998].each{|n| "%6d: %3d %3d\n" \
.printf(n, mdroot(n)...) }
var counter = Hash()
Inf.times { |j|
counter{mdroot(j).first} := [] << j
break if counter.values.all {|v| v.len >= 5 }
}
say "\nMDR: [n0..n4]\n=== ========"
10.times {|i| "%3d: %s\n".printf(i, counter{i}.first(5)) } |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of expression are valued.
Examples may be be split into "setup", "problem statement", and "output" sections where the ease and naturalness of stating the problem and getting an answer, as well as the ease and flexibility of modifying the problem are the primary concerns.
Example output should be shown here, as well as any comments on the examples flexibility.
The problem
Baker, Cooper, Fletcher, Miller, and Smith live on different floors of an apartment house that contains only five floors.
Baker does not live on the top floor.
Cooper does not live on the bottom floor.
Fletcher does not live on either the top or the bottom floor.
Miller lives on a higher floor than does Cooper.
Smith does not live on a floor adjacent to Fletcher's.
Fletcher does not live on a floor adjacent to Cooper's.
Where does everyone live?
| #Picat | Picat | import util.
import cp.
dinesman_cp =>
println(dinesman_cp),
N = 5,
X = [Baker, Cooper, Fletcher, Miller, Smith],
X :: 1..N,
all_different(X),
% Baker does not live on the fifth floor.
Baker #!= 5,
% Cooper does not live on the first floor.
Cooper #!= 1,
% Fletcher does not live on either the fifth or the first floor.
Fletcher #!= 5,
Fletcher #!= 1,
% Miller lives on a higher floor than does Cooper.
Miller #> Cooper,
% Smith does not live on a floor adjacent to Fletcher'.
abs(Smith-Fletcher) #> 1,
% Fletcher does not live on a floor adjacent to Cooper's.
abs(Fletcher-Cooper) #> 1,
solve(X),
println([baker=Baker, cooper=Cooper, fletcher=Fletcher, miller=Miller, smith=Smith]). |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot product of two vectors directly:
each vector must be the same length
multiply corresponding terms from each vector
sum the products (to produce the answer)
Related task
Vector products
| #Icon_and_Unicon | Icon and Unicon | procedure main()
write("a dot b := ",dotproduct([1, 3, -5],[4, -2, -1]))
end
procedure dotproduct(a,b) #: return dot product of vectors a & b or error
if *a ~= *b & type(a) == type(b) == "list" then runerr(205,a) # invalid value
every (dp := 0) +:= a[i := 1 to *a] * b[i]
return dp
end |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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
| #Lua | Lua | function squeezable(s, rune)
print("squeeze: `" .. rune .. "`")
print("old: <<<" .. s .. ">>>, length = " .. string.len(s))
local last = nil
local le = 0
io.write("new: <<<")
for c in s:gmatch"." do
if c ~= last or c ~= rune then
io.write(c)
le = le + 1
end
last = c
end
print(">>>, length = " .. le)
print()
end
function main()
squeezable("", ' ');
squeezable("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ", '-')
squeezable("..1111111111111111111111111111111111111111111111111111111111111117777888", '7')
squeezable("I never give 'em hell, I just tell the truth, and they think it's hell. ", '.')
local s = " --- Harry S Truman "
squeezable(s, ' ')
squeezable(s, '-')
squeezable(s, 'r')
end
main() |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead of any character that is immediately repeated.
If a character string has a specified immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
A specified immediately repeated character is any specified character that is immediately
followed by an identical character (or characters). Another word choice could've been duplicated
character, but that might have ruled out (to some readers) triplicated characters ··· or more.
{This Rosetta Code task was inspired by a newly introduced (as of around
November 2019) PL/I BIF: squeeze.}
Examples
In the following character string with a specified immediately repeated character of e:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!
Only the 2nd e is an specified repeated character, indicated by an underscore
(above), even though they (the characters) appear elsewhere in the character string.
So, after squeezing the string, the result would be:
The better the 4-whel drive, the further you'll be from help when ya get stuck!
Another example:
In the following character string, using a specified immediately repeated character s:
headmistressship
The "squeezed" string would be:
headmistreship
Task
Write a subroutine/function/procedure/routine··· to locate a specified immediately repeated character
and squeeze (delete) them from the character string. The
character string can be processed from either direction.
Show all output here, on this page:
the specified repeated character (to be searched for and possibly squeezed):
the original string and its length
the resultant string and its length
the above strings should be "bracketed" with <<< and >>> (to delineate blanks)
«««Guillemets may be used instead for "bracketing" for the more artistic programmers, shown used here»»»
Use (at least) the following five strings, all strings are length seventy-two (characters, including blanks), except
the 1st string:
immediately
string repeated
number character
( ↓ a blank, a minus, a seven, a period)
╔╗
1 ║╚═══════════════════════════════════════════════════════════════════════╗ ' ' ◄■■■■■■ a null string (length zero)
2 ║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║ '-'
3 ║..1111111111111111111111111111111111111111111111111111111111111117777888║ '7'
4 ║I never give 'em hell, I just tell the truth, and they think it's hell. ║ '.'
5 ║ --- Harry S Truman ║ (below) ◄■■■■■■ has many repeated blanks
╚════════════════════════════════════════════════════════════════════════╝ ↑
│
│
For the 5th string (Truman's signature line), use each of these specified immediately repeated characters:
• a blank
• a minus
• a lowercase r
Note: there should be seven results shown, one each for the 1st four strings, and three results for
the 5th string.
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
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[Squeeze]
Squeeze[s_String,sq_String]:=StringReplace[s,x:(sq..):>sq]
s={
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I never give 'em hell, I just tell the truth, and they think it's hell. ",
" --- Harry S Truman "
};
Squeeze[s[[1]],""]
Squeeze[s[[2]],"-"]
Squeeze[s[[3]],"7"]
Squeeze[s[[4]],"."]
Squeeze[s[[5]]," "]
Squeeze[s[[5]],"-"]
Squeeze[s[[5]],"r"] |
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