Determine if a string is collapsible: Difference between revisions
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* On the Interface Pane, in the Command Center, type "demo" and hit enter. |
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Revision as of 14:31, 18 April 2022
You are encouraged to solve this task according to the task description, using any language you may know.
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 ╚════════════════════════════════════════════════════════════════════════╝
- Metrics
- 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
11l
<lang 11l>F collapse(s)
V cs = ‘’ V last = Char("\0") L(c) s I c != last cs ‘’= c last = c R cs
V 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 ’, ‘The better the 4-wheel drive, the further you'll be from help when ya get stuck!’, ‘headmistressship’, ‘aardvark’
]
L(s) strings
V c = collapse(s) print(‘original : length = ’s.len‘, string = <<<’s‘>>>’) print(‘collapsed : length = ’c.len‘, string = <<<’c‘>>>’) print()</lang>
- Output:
original : length = 0, string = <<<>>> collapsed : length = 0, string = <<<>>> original : length = 72, string = <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> collapsed : length = 70, string = <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> original : length = 72, string = <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> collapsed : length = 4, string = <<<.178>>> original : length = 72, string = <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> collapsed : length = 69, string = <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> original : length = 72, string = <<< --- Harry S Truman >>> collapsed : length = 17, string = <<< - Hary S Truman >>> original : length = 80, string = <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> collapsed : length = 77, string = <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> original : length = 16, string = <<<headmistressship>>> collapsed : length = 14, string = <<<headmistreship>>> original : length = 8, string = <<<aardvark>>> collapsed : length = 7, string = <<<ardvark>>>
8080 Assembly
<lang 8080asm>bdos: equ 5 puts: equ 9 org 100h jmp main ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Collapse the $-terminated string at [HL] colaps: mov b,m ; B = last character seen inx h ; First character never collapses mov d,h ; DE = output pointer mov e,l mov a,b ; Empty string? cpi '$' rz ; Then do nothing cloop: mov a,m ; Get character inx h ; Advance pointer cmp b ; Same as last one? jz cloop ; Then keep scanning mov b,a ; Otherwise, it is a new one stax d ; Store it, inx d ; and increment output pointer. cpi '$' ; Reached the end? jnz cloop ; If not, next character ret ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Code to print the output in the required format main: lxi h,strs ; List of string pointers loop: mov e,m ; DE = string pointer inx h mov d,m inx h mov a,e ; If zero, end ora d rz push h ; Keep the list pointer push d ; Keep the string pointer call brstr ; Print original string in brackets pop h ; Retrieve string pointer push h call colaps ; Collapse the string pop d ; Retrieve string pointer call brstr ; Print the collapsed string in brackets pop h ; Retrieve the list pointer jmp loop ; Next string ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Print string at DE in brackets with length brstr: push d ; Store string pointer mvi c,puts ; Print opening brackets lxi d,open call bdos pop d ; Print original string push d mvi c,puts call bdos mvi c,puts ; Print closing brackets lxi d,close call bdos pop h call strlen ; Find string length mov a,b jmp prnum ; Print string length ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Figure out the length of a string (max 255) strlen: mvi b,0 ; Counter mvi a,'$' ; Terminator sloop: cmp m ; Reached the end yet? rz ; If so, stop inr b ; If not, increment counter, inx h ; and pointer, jmp sloop ; and check next byte. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Print number in A as decimal prnum: lxi d,num ; End of number string prdgt: mvi b,-1 ; Quotient ploop: inr b ; Increment quotient sui 10 ; Subtract 10 jnc ploop ; Subtract until negative adi '0'+10 ; Make ASCII digit dcx d ; Store in number string stax d mov a,b ; If more digits, ana a jnz prdgt ; find next digit mvi c,puts ; When done, print string jmp bdos ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Formatting strings open: db '<<<$' close: db '>>> $' db '***' num: db 13,10,'$' ;;; Input strings strs: dw str1,str2,str3,str4,str5,0 str1: db '$' ; Empty string str2: db '"If I were two-faced, would I be wearing ' db 'this one?" --- Abraham Lincoln $' str3: db '..111111111111111111111111111111111111111' db '1111111111111111111111117777888$' str4: db 'I never give ',39,'em hell, I just tell the truth, ' db 'and they think it',39,'s hell. $' str5: db ' ' db ' --- Harry S Truman $'</lang>
- Output:
<<<>>> 0 <<<>>> 0 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> 72 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> 70 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> 72 <<<.178>>> 4 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> 72 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> 69 <<< --- Harry S Truman >>> 72 <<< - Hary S Truman >>> 17
Action!
<lang Action!>PROC Collapse(CHAR ARRAY in,out)
BYTE i,j CHAR c
j=1 c=0 FOR i=1 TO in(0) DO IF in(i)#c THEN c=in(i) out(j)=c j==+1 FI OD out(0)=j-1
RETURN
PROC Test(CHAR ARRAY s)
CHAR ARRAY c(100) BYTE CH=$02FC ;Internal hardware value for last key pressed
Collapse(s,c) PrintF("<<<%S>>> (len=%B)%E",s,s(0)) PrintF("<<<%S>>> (len=%B)%E",c,c(0)) PutE() PrintE("Press any key to continue") PutE()
DO UNTIL CH#$FF OD CH=$FF
RETURN
PROC Main()
Test("") Test("""If I were two-faced, would I be wearing this one?"" --- Abraham Lincoln ") Test("..1111111111111111111111111111111111111111111111111111111111111117777888") Test("I never give 'em hell, I just tell the truth, and they think it's hell. ") Test(" --- Harry S Truman ")
RETURN</lang>
- Output:
Screenshot from Atari 8-bit computer
<<<>>> (len=0) <<<>>> (len=0) <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> (len=72) <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> (len=70) <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (len=72) <<<.178>>> (len=4) <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (len=72) <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (len=69) <<< --- Harry S Truman >>> (len=72) <<< - Hary S Truman >>> (len=17)
Ada
<lang Ada>with Ada.Text_IO; use Ada.Text_IO; procedure Test_Collapsible is
procedure Collapse (S : in String) is Res : String (1 .. S'Length); Len : Natural := 0; begin Put_Line ("Input = <<<" & S & ">>>, length =" & S'Length'Image); for I in S'Range loop if Len = 0 or else S(I) /= Res(Len) then Len := Len + 1; Res(Len) := S(I); end if; end loop; Put_Line ("Output = <<<" & Res (1 .. Len) & ">>>, length =" & Len'Image); end Collapse;
begin
Collapse (""); Collapse ("""If I were two-faced, would I be wearing this one?"" --- Abraham Lincoln "); Collapse ("..1111111111111111111111111111111111111111111111111111111111111117777888"); Collapse ("I never give 'em hell, I just tell the truth, and they think it's hell. "); Collapse (" --- Harry S Truman ");
end Test_Collapsible; </lang>
- Output:
Input = <<<>>>, length = 0 Output = <<<>>>, length = 0 Input = <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>>, length = 72 Output = <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>>, length = 70 Input = <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>>, length = 72 Output = <<<.178>>>, length = 4 Input = <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>>, length = 72 Output = <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>>, length = 69 Input = <<< --- Harry S Truman >>>, length = 72 Output = <<< - Hary S Truman >>>, length = 17
ALGOL 68
<lang algol68>BEGIN
# returns a collapsed version of s # # i.e. s with adjacent duplicate characters removed # PROC collapse = ( STRING s )STRING: IF s = "" THEN "" # empty string # ELSE # non-empty string # [ LWB s : UPB s ]CHAR result; INT r pos := LWB result; result[ r pos ] := s[ LWB s ]; FOR s pos FROM LWB s + 1 TO UPB s DO IF result[ r pos ] /= s[ s pos ] THEN r pos +:= 1; result[ r pos ] := s[ s pos ] FI OD; result[ LWB result : r pos ] FI # callapse # ; # task test cases # []STRING tests = ( "" , """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 t pos FROM LWB tests TO UPB tests DO STRING s = tests[ t pos ]; STRING c = collapse( s ); print( ( " <<<", s, ">>> (length ", whole( ( UPB s + 1 ) - LWB s, 0 ), ")", newline ) ); print( ( "result <<<", c, ">>> (length ", whole( ( UPB c + 1 ) - LWB c, 0 ), ")", newline ) ) OD
END </lang>
- Output:
<<<>>> (length 0) result <<<>>> (length 0) <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> (length 72) result <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> (length 70) <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (length 72) result <<<.178>>> (length 4) <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (length 72) result <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (length 69) <<< --- Harry S Truman >>> (length 72) result <<< - Hary S Truman >>> (length 17)
APL
<lang APL>task←{
⍝ Collapse a string collapse←{(1,¯1↓⍵≠1⌽⍵)/⍵}
⍝ Given a function ⍺⍺, display a string in brackets, ⍝ along with its length, and do the same for the result ⍝ of applying ⍺⍺ to the string. display←{ bracket←{(⍕⍴⍵),' «««',⍵,'»»»'} ↑(⊂bracket ⍵),(⊂bracket ⍺⍺ ⍵) }
⍝ Strings from the task s1← s2←'"If I were two-faced, would I be wearing this one?"' s2,←' --- Abraham Lincoln ' s3←'..1111111111111111111111111111111111111111111111111' s3,←'111111111111117777888' s4←'I never give em hell, I just tell the truth, ' s4,←'and they think its hell. ' s5←' ' s5,←' --- Harry S Truman ' strs←s1 s2 s3 s4 s5
⍝ Collapse each string and display it as specified ↑collapse display¨ strs
}</lang>
- Output:
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 »»»
AutoHotkey
<lang AutoHotkey>collapsible_string(str){ for i, ch in StrSplit(str){ if (ch <> prev) res .= ch prev := ch } return "original string:`t" StrLen(str) " characters`t«««" str "»»»`nresultant string:`t" StrLen(res) " characters`t«««" res "»»»" }</lang> Examples:<lang AutoHotkey>data := ["" , """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 i, v in data MsgBox % := collapsible_string(v) return</lang>
Outputs:
----------------------------------------- original string: 0 characters «««»»» resultant string: 0 characters «««»»» ----------------------------------------- original string: 72 characters «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» resultant string: 70 characters «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» ----------------------------------------- original string: 72 characters «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» resultant string: 4 characters «««.178»»» ----------------------------------------- original string: 72 characters «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» resultant string: 69 characters «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» ----------------------------------------- original string: 72 characters ««« --- Harry S Truman »»» resultant string: 17 characters ««« - Hary S Truman »»» -----------------------------------------
AWK
<lang AWK>
- syntax: GAWK -f DETERMINE_IF_A_STRING_IS_COLLAPSIBLE.AWK
BEGIN {
for (i=1; i<=9; i++) { for (j=1; j<=i; j++) { arr[0] = arr[0] i } } arr[++n] = "" arr[++n] = "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln " arr[++n] = "..1111111111111111111111111111111111111111111111111111111111111117777888" arr[++n] = "I never give 'em hell, I just tell the truth, and they think it's hell. " arr[++n] = " --- Harry S Truman " arr[++n] = "The better the 4-wheel drive, the further you'll be from help when ya get stuck!" arr[++n] = "headmistressship" for (i=0; i<=n; i++) { main(arr[i]) } exit(0)
} function main(str, c,i,new_str,prev_c) {
for (i=1; i<=length(str); i++) { c = substr(str,i,1) if (prev_c != c) { prev_c = c new_str = new_str c } } printf("old: %2d <<<%s>>>\n",length(str),str) printf("new: %2d <<<%s>>>\n\n",length(new_str),new_str)
} </lang>
- Output:
old: 45 <<<122333444455555666666777777788888888999999999>>> new: 9 <<<123456789>>> old: 0 <<<>>> new: 0 <<<>>> old: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> new: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> old: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> new: 4 <<<.178>>> old: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> new: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> old: 72 <<< --- Harry S Truman >>> new: 17 <<< - Hary S Truman >>> old: 80 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> new: 77 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> old: 16 <<<headmistressship>>> new: 14 <<<headmistreship>>>
BaCon
<lang bacon>DATA "" DATA "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln " DATA "..1111111111111111111111111111111111111111111111111111111111111117777888" DATA "I never give 'em hell, I just tell the truth, and they think it's hell. " DATA " --- Harry S Truman " DATA "The better the 4-wheel drive, the further you'll be from help when ya get stuck!" DATA "headmistressship"
DOTIMES 7
READ x$ found = 0 PRINT "<<<", x$, ">>> - length: ", LEN(x$) PRINT "<<<"; FOR y = 1 TO LEN(x$) IF MID$(x$, y, 1) <> MID$(x$, y+1, 1) THEN PRINT MID$(x$, y, 1); INCR found ENDIF NEXT PRINT ">>> - length: ", found
DONE</lang>
- Output:
<<<>>> - length: 0 <<<>>> - length: 0 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> - length: 72 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> - length: 70 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> - length: 72 <<<.178>>> - length: 4 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> - length: 72 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> - length: 69 <<< --- Harry S Truman >>> - length: 72 <<< - Hary S Truman >>> - length: 17 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> - length: 80 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> - length: 77 <<<headmistressship>>> - length: 16 <<<headmistreship>>> - length: 14
BASIC
<lang basic>10 READ N% 20 FOR A% = 1 TO N% 30 READ I$: GOSUB 100 40 PRINT LEN(I$); "<<<"; I$; ">>>" 50 PRINT LEN(O$); "<<<"; O$; ">>>" 55 PRINT 60 NEXT 70 END 100 REM Collapse I$ into O$ 105 IF I$="" THEN O$=I$: RETURN 110 O$=SPACE$(LEN(I$)) 120 P$=LEFT$(I$,1) 130 MID$(O$,1,1)=P$ 140 O%=2 150 FOR I%=2 TO LEN(I$) 160 C$=MID$(I$,I%,1) 170 IF P$<>C$ THEN MID$(O$,O%,1)=C$: O%=O%+1: P$=C$ 180 NEXT 190 O$=LEFT$(O$,O%-1) 200 RETURN 400 DATA 5: REM There are 5 strings 410 DATA "" 420 DATA "'If I were two-faced, would I be wearing this one?' --- Abraham Lincoln " 430 DATA "..1111111111111111111111111111111111111111111111111111111111111117777888" 440 DATA "I never give 'em hell, I just tell the truth, and they think it's hell. " 450 DATA " --- Harry S Truman "</lang>
- Output:
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 >>>
BCPL
<lang bcpl>get "libhdr"
// Collapse a string let collapse(in, out) = valof $( let o = 0
for i = 1 to in%0 unless i>1 & in%i = in%(i-1) $( o := o + 1 out%o := in%i $) out%0 := o resultis out
$)
// Print string with brackets and length let brackets(s) be
writef("%N: <<<%S>>>*N", s%0, s)
// Print original and collapsed version let show(s) be $( let v = vec 1+255/BYTESPERWORD
brackets(s) brackets(collapse(s, v)) wrch('*N')
$)
let start() be $( show("")
show("*"If I were two-faced, would I be wearing this one?*" --- Abraham Lincoln ") show("..1111111111111111111111111111111111111111111111111111111111111111111788") show("I never give 'em hell, I just tell the truth, and they think it's hell. ") show(" --- Harry S Truman ")
$)</lang>
- Output:
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: <<<..1111111111111111111111111111111111111111111111111111111111111111111788>>> 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 >>>
Bracmat
<lang Bracmat> ( colapse
= previous . str $ ( vap $ ( ( = . !arg:!previous& | !arg:?previous ) . !arg ) ) )
& ( testcolapse
= len . (len=.@(!arg:? [?arg)&!arg) & out$(str$(««« !arg "»»» " len$!arg)) & colapse$!arg:?arg & out$(str$(««« !arg "»»» " len$!arg)) )
& testcolapse$ & testcolapse
$ "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln "
& testcolapse
$ "..1111111111111111111111111111111111111111111111111111111111111117777888"
& testcolapse
$ "I never give 'em hell, I just tell the truth, and they think it's hell. "
& testcolapse
$ " --- Harry S Truman "</lang>
Output
«««»»» 0 «««»»» 0 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» 72 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» 70 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» 72 «««.178»»» 4 «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» 72 «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» 69 ««« --- Harry S Truman »»» 72 ««« - Hary S Truman »»» 17
C
Identical implementation as in Determine_if_a_string_is_squeezable, as both tasks are very similar. The Lincoln quote contains backslashes to accommodate the double quotes via the command line. strcmpi is not part of the C Standard Library, thus comment out the definition in the code if testing on a system where it is already included.
<lang C>
- include<string.h>
- include<stdlib.h>
- include<stdio.h>
- define COLLAPSE 0
- define SQUEEZE 1
typedef struct charList{
char c; struct charList *next;
} charList;
/* Implementing strcmpi, the case insensitive string comparator, as it is not part of the C Standard Library.
Comment this out if testing on a compiler where it is already defined.
- /
int strcmpi(char* str1,char* str2){
int len1 = strlen(str1), len2 = strlen(str2), i;
if(len1!=len2){ return 1; }
else{ for(i=0;i<len1;i++){ if((str1[i]>='A'&&str1[i]<='Z')&&(str2[i]>='a'&&str2[i]<='z')&&(str2[i]-65!=str1[i])) return 1; else if((str2[i]>='A'&&str2[i]<='Z')&&(str1[i]>='a'&&str1[i]<='z')&&(str1[i]-65!=str2[i])) return 1; else if(str1[i]!=str2[i]) return 1; } }
return 0;
}
charList *strToCharList(char* str){
int len = strlen(str),i;
charList *list, *iterator, *nextChar;
list = (charList*)malloc(sizeof(charList)); list->c = str[0]; list->next = NULL;
iterator = list;
for(i=1;i<len;i++){ nextChar = (charList*)malloc(sizeof(charList)); nextChar->c = str[i]; nextChar->next = NULL;
iterator->next = nextChar; iterator = nextChar; }
return list;
}
char* charListToString(charList* list){
charList* iterator = list; int count = 0,i; char* str;
while(iterator!=NULL){ count++; iterator = iterator->next; }
str = (char*)malloc((count+1)*sizeof(char)); iterator = list;
for(i=0;i<count;i++){ str[i] = iterator->c; iterator = iterator->next; }
free(list); str[i] = '\0';
return str;
}
char* processString(char str[100],int operation, char squeezeChar){
charList *strList = strToCharList(str),*iterator = strList, *scout;
if(operation==SQUEEZE){ while(iterator!=NULL){ if(iterator->c==squeezeChar){ scout = iterator->next;
while(scout!=NULL && scout->c==squeezeChar){ iterator->next = scout->next; scout->next = NULL; free(scout); scout = iterator->next; } } iterator = iterator->next; } }
else{ while(iterator!=NULL && iterator->next!=NULL){ if(iterator->c == (iterator->next)->c){ scout = iterator->next; squeezeChar = iterator->c;
while(scout!=NULL && scout->c==squeezeChar){ iterator->next = scout->next; scout->next = NULL; free(scout); scout = iterator->next; } } iterator = iterator->next; } }
return charListToString(strList);
}
void printResults(char originalString[100], char finalString[100], int operation, char squeezeChar){
if(operation==SQUEEZE){ printf("Specified Operation : SQUEEZE\nTarget Character : %c",squeezeChar); }
else printf("Specified Operation : COLLAPSE");
printf("\nOriginal %c%c%c%s%c%c%c\nLength : %d",174,174,174,originalString,175,175,175,(int)strlen(originalString)); printf("\nFinal %c%c%c%s%c%c%c\nLength : %d\n",174,174,174,finalString,175,175,175,(int)strlen(finalString));
}
int main(int argc, char** argv){
int operation; char squeezeChar;
if(argc<3||argc>4){ printf("Usage : %s <SQUEEZE|COLLAPSE> <String to be processed> <Character to be squeezed, if operation is SQUEEZE>\n",argv[0]); return 0; }
if(strcmpi(argv[1],"SQUEEZE")==0 && argc!=4){ scanf("Please enter characted to be squeezed : %c",&squeezeChar); operation = SQUEEZE; }
else if(argc==4){ operation = SQUEEZE; squeezeChar = argv[3][0]; }
else if(strcmpi(argv[1],"COLLAPSE")==0){ operation = COLLAPSE; }
if(strlen(argv[2])<2){ printResults(argv[2],argv[2],operation,squeezeChar); }
else{ printResults(argv[2],processString(argv[2],operation,squeezeChar),operation,squeezeChar); } return 0;
} </lang> Output :
C:\My Projects\networks>a collapse "The better the 4-wheel drive, the further you'll be from help when ya get stuck!" Specified Operation : COLLAPSE Original «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» Length : 80 Final «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» Length : 77 C:\My Projects\networks>a collapse headmistressship Specified Operation : COLLAPSE Original «««headmistressship»»» Length : 16 Final «««headmistreship»»» Length : 14 C:\My Projects\networks>a collapse "" Specified Operation : COLLAPSE Original «««»»» Length : 0 Final «««»»» Length : 0 C:\My Projects\networks>a collapse "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln" Specified Operation : COLLAPSE Original «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln»»» Length : 71 Final «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln»»» Length : 69 C:\My Projects\networks>a collapse ..1111111111111111111111111111111111111111111111111111111111111117777888 Specified Operation : COLLAPSE Original «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» Length : 72 Final «««.178»»» Length : 4 C:\My Projects\networks>a collapse "I never give 'em hell, I just tell the truth, and they think it's hell." Specified Operation : COLLAPSE Original «««I never give 'em hell, I just tell the truth, and they think it's hell.»»» Length : 71 Final «««I never give 'em hel, I just tel the truth, and they think it's hel.»»» Length : 68 C:\My Projects\networks>a collapse " --- Harry S Truman" Specified Operation : COLLAPSE Original ««« --- Harry S Truman»»» Length : 70 Final ««« - Hary S Truman»»» Length : 16
C#
<lang csharp>using System; using static System.Linq.Enumerable;
public class Program {
static void Main() { 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 " }; foreach (string s in input) { Console.WriteLine($"old: {s.Length} «««{s}»»»"); string c = Collapse(s); Console.WriteLine($"new: {c.Length} «««{c}»»»"); } }
static string Collapse(string s) => string.IsNullOrEmpty(s) ? "" : s[0] + new string(Range(1, s.Length - 1).Where(i => s[i] != s[i - 1]).Select(i => s[i]).ToArray());
}</lang>
- Output:
old: 0 «««»»» new: 0 «««»»» old: 80 «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» new: 77 «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» old: 16 «««headmistressship»»» new: 14 «««headmistreship»»» old: 72 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» new: 70 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» old: 72 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» new: 4 «««.178»»» old: 72 «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» new: 69 «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» old: 72 ««« --- Harry S Truman »»» new: 17 ««« - Hary S Truman »»»
C++
The solution is a straightforward application of the standard library function "unique". <lang cpp>#include <string>
- include <iostream>
- include <algorithm>
template<typename char_type> std::basic_string<char_type> collapse(std::basic_string<char_type> str) {
auto i = std::unique(str.begin(), str.end()); str.erase(i, str.end()); return str;
}
void test(const std::string& str) {
std::cout << "original string: <<<" << str << ">>>, length = " << str.length() << '\n'; std::string collapsed(collapse(str)); std::cout << "result string: <<<" << collapsed << ">>>, length = " << collapsed.length() << '\n'; std::cout << '\n';
}
int main(int argc, char** argv) {
test(""); test("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln "); test("..1111111111111111111111111111111111111111111111111111111111111117777888"); test("I never give 'em hell, I just tell the truth, and they think it's hell. "); test(" --- Harry S Truman "); return 0;
}</lang>
- Output:
original string: <<<>>>, length = 0 result string: <<<>>>, length = 0 original string: <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>>, length = 72 result string: <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>>, length = 70 original string: <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>>, length = 72 result string: <<<.178>>>, length = 4 original string: <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>>, length = 72 result string: <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>>, length = 69 original string: <<< --- Harry S Truman >>>, length = 72 result string: <<< - Hary S Truman >>>, length = 17
Clojure
<lang Clojure> (defn collapse [s]
(let [runs (partition-by identity s)] (apply str (map first runs))))
(defn run-test [s]
(let [out (collapse s)] (str (format "Input: <<<%s>>> (len %d)\n" s (count s)) (format "becomes: <<<%s>>> (len %d)\n" out (count out)))))
</lang>
- Output:
Input: <<<>>> (len 0) becomes: <<<>>> (len 0) Input: <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> (len 72) becomes: <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> (len 70) Input: <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (len 72) becomes: <<<.178>>> (len 4) Input: <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (len 72) becomes: <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (len 69) Input: <<< --- Harry S Truman >>> (len 72) becomes: <<< - Hary S Truman >>> (len 17)
CLU
<lang clu>% Collapse a string collapse = proc (s: string) returns (string)
out: array[char] := array[char]$[] last: char := '\000' for c: char in string$chars(s) do if c ~= last then last := c array[char]$addh(out,c) end end return (string$ac2s(out))
end collapse
% Show a string in brackets, with its length brackets = proc (s: string)
stream$putl(stream$primary_output(), int$unparse(string$size(s)) || " <<<" || s || ">>>")
end brackets
% Show a string and its collapsed version, and the corresponding lengths show = proc (s: string)
brackets(s) brackets(collapse(s)) stream$putl(stream$primary_output(), "")
end show
% Try the examples from the task description start_up = proc ()
examples: array[string] := array[string]$[ "", "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ", "..1111111111111111111111111111111111111111111111111111111111111117777888", "I never give 'em hell, I just tell the truth, and they think it's hell. ", " --- Harry S Truman " ] for ex: string in array[string]$elements(examples) do show(ex) end
end start_up</lang>
- Output:
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 >>>
Cowgol
<lang cowgol>include "cowgol.coh"; include "strings.coh";
- Collapse the string at in, and store the result in the given buffer
sub collapse(in: [uint8], out: [uint8]) is
var ch := [in]; in := @next in; loop if ch == 0 then [out] := 0; return; elseif [in] != ch then [out] := ch; out := @next out; ch := [in]; end if; in := @next in; end loop;
end sub;
- Given a string, collapse it and print all required output
sub show(str: [uint8]) is
sub bracket_length(str: [uint8]) is print_i32(StrLen(str) as uint32); print(" <<<"); print(str); print(">>>"); print_nl(); end sub; var buf: uint8[256]; collapse(str, &buf[0]); bracket_length(str); bracket_length(&buf[0]); print_nl();
end sub;
- Strings from the task
var strings: [uint8][] := { "", "\"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 and print each string
var i: @indexof strings := 0; while i < @sizeof strings loop
show(strings[i]); i := i + 1;
end loop;</lang>
- Output:
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 >>>
D
<lang d>import std.stdio;
void collapsible(string s) {
writeln("old: <<<", s, ">>>, length = ", s.length);
write("new: <<<"); char last = '\0'; int len = 0; foreach (c; s) { if (c != last) { write(c); len++; } last = c; } writeln(">>>, length = ", len);
writeln;
}
void main() {
collapsible(``); collapsible(`"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln `); collapsible(`..1111111111111111111111111111111111111111111111111111111111111117777888`); collapsible(`I never give 'em hell, I just tell the truth, and they think it's hell. `); collapsible(` --- Harry S Truman `);
}</lang>
- Output:
old: <<<>>>, length = 0 new: <<<>>>, length = 0 old: <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>>, length = 72 new: <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>>, length = 70 old: <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>>, length = 72 new: <<<.178>>>, length = 4 old: <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>>, length = 72 new: <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>>, length = 69 old: <<< --- Harry S Truman >>>, length = 72 new: <<< - Hary S Truman >>>, length = 17
Delphi
<lang Delphi> program Determine_if_a_string_is_collapsible;
{$APPTYPE CONSOLE}
uses
System.SysUtils;
procedure collapsible(s: string); var
c, last: char; len: Integer;
begin
writeln('old: <<<', s, '>>>, length = ', s.length); write('new: <<<'); last := #0; len := 0; for c in s do begin if c <> last then begin write(c); inc(len); end; last := c; end; writeln('>>>, length = ', len, #10);
end;
begin
collapsible(); collapsible('"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln '); collapsible('..1111111111111111111111111111111111111111111111111111111111111117777888'); collapsible('I never give em hell, I just tell the truth, and they think its hell. '); collapsible(' --- Harry S Truman '); readln;
end.</lang>
F#
<lang fsharp> // Collapse a String. Nigel Galloway: June 9th., 2020 //As per the task description a function which 'determines if a character string is collapsible' by testing if any consecutive characters are the same. let isCollapsible n=n|>Seq.pairwise|>Seq.tryFind(fun(n,g)->n=g) //As per the task description a function which 'if the string is collapsable, collapses the string (by removing immediately repeated characters). let collapse n=match isCollapsible n with
Some _->let i=Seq.head n let fN=let mutable g=i in (fun n->if n=g then false else g<-n; true) let g=System.String([|yield i;yield! Seq.tail n|>Seq.filter fN|]) printfn "<<<%s>>> (length %d) colapses to <<<%s>>> (length %d)" n n.Length g g.Length | _->printfn "<<<%s>>> (length %d) does not colapse" n n.Length
collapse "" collapse "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln " collapse "..1111111111111111111111111111111111111111111111111111111111111117777888" collapse "I never give 'em hell, I just tell the truth, and they think it's hell. " collapse " --- Harry S Truman " collapse "withoutConsecutivelyRepeatedCharacters" </lang>
- Output:
<<<>>> (length 0) does not colapse <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> (length 72) collapses to <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> (length 70) <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (length 72) collapses to <<<.178>>> (length 4) <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (length 72) collapses to <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (length 69) <<< --- Harry S Truman >>> (length 72) collapses to <<< - Hary S Truman >>> (length 17) <<<withoutConsecutivelyRepeatedCharacters>>> (length 38) does not collapse
Factor
<lang factor>USING: formatting io kernel sbufs sequences strings ; IN: rosetta-code.string-collapse
- (collapse) ( str -- str )
unclip-slice 1string >sbuf [ over last over = [ drop ] [ suffix! ] if ] reduce >string ;
- collapse ( str -- str ) [ "" ] [ (collapse) ] if-empty ;
- .str ( str -- ) dup length "«««%s»»» (length %d)\n" printf ;
- show-collapse ( str -- )
[ "Before collapse: " write .str ] [ "After collapse: " write collapse .str ] bi nl ;
- collapse-demo ( -- )
{ "" "\"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" "😍😀🙌💃😍😍😍🙌" } [ show-collapse ] each ;
MAIN: collapse-demo</lang>
- Output:
(Using some extra test cases from the Go entry.)
Before collapse: «««»»» (length 0) After collapse: «««»»» (length 0) Before collapse: «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» (length 72) After collapse: «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» (length 70) Before collapse: «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» (length 72) After collapse: «««.178»»» (length 4) Before collapse: «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» (length 72) After collapse: «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» (length 69) Before collapse: ««« --- Harry S Truman »»» (length 72) After collapse: ««« - Hary S Truman »»» (length 17) Before collapse: «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» (length 80) After collapse: «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» (length 77) Before collapse: «««headmistressship»»» (length 16) After collapse: «««headmistreship»»» (length 14) Before collapse: «««aardvark»»» (length 8) After collapse: «««ardvark»»» (length 7) Before collapse: «««😍😀🙌💃😍😍😍🙌»»» (length 8) After collapse: «««😍😀🙌💃😍🙌»»» (length 6)
FreeBASIC
<lang freebasic>Const numCad = 5 Data "" Data "'If I were two-faced, would I be wearing this one?' --- Abraham Lincoln " Data "..1111111111111111111111111111111111111111111111111111111111111117777888" Data "I never give 'em hell, I just tell the truth, and they think it's hell. " Data " --- Harry S Truman "
Dim Shared As String cadIN, cadOUT
Sub Collapse
Dim As String a, b If cadIN = "" Then cadOUT = cadIN: Exit Sub cadOUT = Space(Len(cadIN)) a = Left(cadIN,1) Mid(cadOUT,1,1) = a Dim As Integer txtOUT = 2 For i As Integer = 2 To Len(cadIN) b = Mid(cadIN,i,1) If a <> b Then Mid(cadOUT,txtOUT,1) = b: txtOUT += 1: a = b Next i cadOUT = Left(cadOUT,txtOUT-1)
End Sub
For j As Integer = 1 To numCad
Read cadIN Collapse Print " <<<"; cadIN; ">>> (longitud "; Len(cadIN); _ !")\n se pliega a:\n <<<"; cadOUT; ">>> (longitud "; Len(cadOUT); !")\n"
Next j Sleep </lang>
- Output:
<<<>>> (longitud 0) se pliega a: <<<>>> (longitud 0) <<<'If I were two-faced, would I be wearing this one?' --- Abraham Lincoln >>> (longitud 72) se pliega a: <<<'If I were two-faced, would I be wearing this one?' - Abraham Lincoln >>> (longitud 70) <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (longitud 72) se pliega a: <<<.178>>> (longitud 4) <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (longitud 72) se pliega a: <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (longitud 69) <<< --- Harry S Truman >>> (longitud 72) se pliega a: <<< - Hary S Truman >>> (longitud 17)
Go
<lang go>package main
import "fmt"
// Returns collapsed string, original and new lengths in // unicode code points (not normalized). func collapse(s string) (string, int, int) {
r := []rune(s) le, del := len(r), 0 for i := le - 2; i >= 0; i-- { if r[i] == r[i+1] { copy(r[i:], r[i+1:]) del++ } } if del == 0 { return s, le, le } r = r[:le-del] return string(r), le, len(r)
}
func main() {
strings:= []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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌", } for _, s := range strings { cs, olen, clen := collapse(s) fmt.Printf("original : length = %2d, string = «««%s»»»\n", olen, s) fmt.Printf("collapsed: length = %2d, string = «««%s»»»\n\n", clen, cs) }
}</lang>
- Output:
original : length = 0, string = «««»»» collapsed: length = 0, string = «««»»» original : length = 72, string = «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» collapsed: length = 70, string = «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» original : length = 72, string = «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» collapsed: length = 4, string = «««.178»»» original : length = 72, string = «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» collapsed: length = 69, string = «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» original : length = 72, string = ««« --- Harry S Truman »»» collapsed: length = 17, string = ««« - Hary S Truman »»» original : length = 80, string = «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» collapsed: length = 77, string = «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» original : length = 16, string = «««headmistressship»»» collapsed: length = 14, string = «««headmistreship»»» original : length = 8, string = «««aardvark»»» collapsed: length = 7, string = «««ardvark»»» original : length = 8, string = «««😍😀🙌💃😍😍😍🙌»»» collapsed: length = 6, string = «««😍😀🙌💃😍🙌»»»
Groovy
<lang groovy>class StringCollapsible {
static void main(String[] args) { for ( String 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 ", "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 input) { StringBuilder sb = new StringBuilder() for ( int i = 0 ; i < input.length() ; i++ ) { if ( i == 0 || input.charAt(i-1) != input.charAt(i) ) { sb.append(input.charAt(i)) } } return sb.toString() }
}</lang>
- Output:
old: 0 <<<>>> new: 0 <<<>>> old: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> new: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> old: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> new: 4 <<<.178>>> old: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> new: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> old: 72 <<< --- Harry S Truman >>> new: 17 <<< - Hary S Truman >>> old: 45 <<<122333444455555666666777777788888888999999999>>> new: 9 <<<123456789>>> old: 80 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> new: 77 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> old: 16 <<<headmistressship>>> new: 14 <<<headmistreship>>>
Haskell
<lang 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</lang>
- Output:
old: 0 «««»»» new: 0 «««»»» old: 80 «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» new: 77 «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» old: 16 «««headmistressship»»» new: 14 «««headmistreship»»» old: 72 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» new: 70 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» old: 72 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» new: 4 «««.178»»» old: 72 «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» new: 69 «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» old: 72 ««« --- Harry S Truman »»» new: 17 ««« - Hary S Truman »»» old: 8 «««😍😀🙌💃😍😍😍🙌»»» new: 6 «««😍😀🙌💃😍🙌»»»
Note that we can also directly define a predicate, and a rewrite, in terms of Data.List group,
<lang haskell>import Data.List (group)
isCollapsible :: String -> Bool isCollapsible = any ((1 <) . length) . group
collapsed :: String -> String collapsed = map head . group</lang>
or, without imports, in terms of pattern matching:
<lang haskell>isCollapsible :: String -> Bool isCollapsible [] = False isCollapsible [_] = False isCollapsible (h:t@(x:_)) = h == x || isCollapsible t
collapsed :: String -> String collapsed [] = [] collapsed [x] = [x] collapsed (h:t@(x:_))
| h == x = collapsed t | otherwise = h : collapsed t</lang>
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 >>>| | |+--+------------------------------------------------------------------------------+|+--+-----------------------+ | +-----------------------------------------------------------------------------------+---------------------------------------------------------------------------------+
Java
<lang 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(); }
} </lang>
- Output:
old: 0 <<<>>> new: 0 <<<>>> old: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> new: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> old: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> new: 4 <<<.178>>> old: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> new: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> old: 72 <<< --- Harry S Truman >>> new: 17 <<< - Hary S Truman >>> old: 45 <<<122333444455555666666777777788888888999999999>>> new: 9 <<<123456789>>> old: 80 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> new: 77 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> old: 16 <<<headmistressship>>> new: 14 <<<headmistreship>>>
JavaScript
<lang 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})`);
} </lang>
- Output:
«««»»» (0) «««»»» (0) «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» (72) «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» (70) «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» (72) «««.178»»» (4) «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» (72) «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» (69) ««« --- Harry S Truman »»» (72) ««« - Hary S Truman »»» (17)
jq
Here we can use the Unix-like `uniq` function defined on (JSON) arrays to define `collapse` on (JSON) strings: <lang 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; </lang>
The program for the given task can now be written in three lines:
<lang jq>def Guillemets: "«««\(.)»»»";
"Original: \(Guillemets) has length \(length)", (collapse | "Collapsed \(Guillemets) has length \(length)") </lang>
Using the following invocation on the five "raw" (i.e. unquoted) strings yields the results as shown:
jq -Rrf program.jq raw.txt
<lang sh>Original: «««»»» has length 0 Collapsed «««»»» has length 0 Original: «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» has length 72 Collapsed «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» has length 70 Original: «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» has length 72 Collapsed «««.178»»» has length 4 Original: «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» has length 72 Collapsed «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» has length 69 Original: ««« --- Harry S Truman »»» has length 72 Collapsed ««« - Hary S Truman »»» has length 17</lang>
Julia
<lang 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 $len2).\n") end
end
testcollapse(teststrings)
</lang>
- Output:
«««»»» (length 0) collapses to: «««»»» (length 0). «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» (length 72) collapses to: «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» (length 70). «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» (length 72) collapses to: «««.178»»» (length 4). «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» (length 72) collapses to: «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» (length 69). ««« --- Harry S Truman »»» (length 72) collapses to: ««« - Hary S Truman »»» (length 17).
Condensed version:
<lang julia>const teststrings = [
"", """"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln """, "..1111111111111111111111111111111111111111111111111111111111111117777888", """I never give 'em hell, I just tell the truth, and they think it's hell. """, " --- Harry S Truman "]
collapse(s) = (t = isempty(s) ? "" : s[1:1]; for c in s if c != t[end] t *= c end; end; t)
for s in teststrings
n, t = length(s), collapse(s) println("«««$s»»» (length $n)\n collapses to:\n«««$t»»» (length $(length(t))).\n")
end </lang>
Kotlin
<lang scala>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() }
}</lang>
- Output:
original : length = 0, string = «««»»» collapsed : length = 0, string = «««»»» original : length = 72, string = «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» collapsed : length = 70, string = «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» original : length = 72, string = «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» collapsed : length = 4, string = «««.178»»» original : length = 72, string = «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» collapsed : length = 69, string = «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» original : length = 72, string = ««« --- Harry S Truman »»» collapsed : length = 17, string = ««« - Hary S Truman »»» original : length = 80, string = «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» collapsed : length = 77, string = «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» original : length = 16, string = «««headmistressship»»» collapsed : length = 14, string = «««headmistreship»»» original : length = 8, string = «««aardvark»»» collapsed : length = 7, string = «««ardvark»»»
Ksh
<lang ksh>
- !/bin/ksh
- Determine if a string is collapsible (repeated letters)
- # Variables:
typeset -a strings strings[0]="" strings[1]='"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln' strings[2]="..1111111111111111111111111111111111111111111111111111111111111117777888" strings[3]="I never give 'em hell, I just tell the truth, and they think it's hell." strings[4]=" --- Harry S Truman"
typeset -a Guillemet=( "«««" "»»»" )
- # Functions:
- # Function _collapse(str) - return colapsed version of str
function _collapse { typeset _str ; _str="$1" typeset _i _buff ; integer _i
for ((_i=1; _i<${#_str}; _i++)); do if [[ "${_str:$((_i-1)):1}" == "${_str:${_i}:1}" ]]; then continue else _buff+=${_str:$((_i-1)):1} fi done [[ "${_str:$((_i-1)):1}" != "${_str:${_i}:1}" ]] && _buff+=${_str:$((_i-1)):1} echo "${_buff}" }
######
- main #
######
for ((i=0; i<${#strings[*]}; i++)); do str=$(_collapse "${strings[i]}") print ${#strings[i]} "${Guillemet[0]}${strings[i]}${Guillemet[1]}" print ${#str} "${Guillemet[0]}${str}${Guillemet[1]}\n" done</lang>
- Output:
0 «««»»»0 «««»»»
71 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln»»» 69 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln»»»
72 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» 4 «««.178»»»
71 «««I never give 'em hell, I just tell the truth, and they think it's hell.»»» 68 «««I never give 'em hel, I just tel the truth, and they think it's hel.»»»
70 ««« --- Harry S Truman»»» 16 ««« - Hary S Truman»»»
Lua
<lang lua>function collapse(s)
local ns = "" local last = nil for c in s:gmatch"." do if last then if last ~= c then ns = ns .. c end last = c else ns = ns .. c last = c end end return ns
end
function test(s)
print("old: " .. s:len() .. " <<<" .. s .. ">>>") local a = collapse(s) print("new: " .. a:len() .. " <<<" .. a .. ">>>")
end
function main()
test("") test("The better the 4-wheel drive, the further you'll be from help when ya get stuck!") test("headmistressship") test("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ") test("..1111111111111111111111111111111111111111111111111111111111111117777888") test("I never give 'em hell, I just tell the truth, and they think it's hell. ") test(" --- Harry S Truman ")
end
main()</lang>
- Output:
old: 0 <<<>>> new: 0 <<<>>> old: 80 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> new: 77 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> old: 16 <<<headmistressship>>> new: 14 <<<headmistreship>>> old: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> new: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> old: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> new: 4 <<<.178>>> old: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> new: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> old: 72 <<< --- Harry S Truman >>> new: 17 <<< - Hary S Truman >>>
Mathematica / Wolfram Language
<lang Mathematica>ClearAll[StringCollapse] StringCollapse[s_String] := FixedPoint[StringReplace[y_ ~~ y_ :> y], s] 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 "}; Do[
Print["«««" <> s <> "»»»"]; Print["Length = ", StringLength[s]]; Print["«««" <> StringCollapse[s] <> "»»»"]; Print["Length = ", StringLength[StringCollapse[s]]] , {s, strings} ]</lang>
- Output:
«««»»» Length = 0 «««»»» Length = 0 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» Length = 72 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» Length = 70 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» Length = 72 «««.178»»» Length = 4 «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» Length = 72 «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» Length = 69 ««« --- Harry S Truman »»» Length = 72 ««« - Hary S Truman »»» Length = 17
MATLAB / Octave
<lang Matlab> function r = collapse(s)
ix=find((s(1:end-1)==s(2:end))+1; r=s; r(ix)=[];
fprintf(1,'Input: <<<%s>>> length: %d\n',s,length(s)); fprintf(1,'Output: <<<%s>>> length: %d\n',r,length(r)); fprintf(1,'Character to be squeezed: "%s"\n',c);
end
collapse(, ' ')
collapse('║╚═══════════════════════════════════════════════════════════════════════╗', '-')
collapse('║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║', '7')
collapse('║..1111111111111111111111111111111111111111111111111111111111111117777888║', '.')
collapse('║I never give em hell, I just tell the truth, and they think its hell. ║', '.')
collapse('║ --- Harry S Truman ║', '.')
collapse('║ --- Harry S Truman ║', '-')
collapse('║ --- Harry S Truman ║', 'r')
</lang>
- Output:
Input: <<<>>> length: 0 Output: <<<>>> length: 0 ans = Input: <<<║╚═══════════════════════════════════════════════════════════════════════╗>>> length: 222 Output: <<<║╚═══════════════════════════════════════════════════════════════════════╗>>> length: 222 ans = ║╚═══════════════════════════════════════════════════════════════════════╗ Input: <<<║"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ║>>> length: 78 Output: <<<║"If I were two-faced, would I be wearing this one?" - Abraham Lincoln ║>>> length: 76 ans = ║"If I were two-faced, would I be wearing this one?" - Abraham Lincoln ║ Input: <<<║..1111111111111111111111111111111111111111111111111111111111111117777888║>>> length: 78 Output: <<<║.178║>>> length: 10 ans = ║.178║ Input: <<<║I never give 'em hell, I just tell the truth, and they think it's hell. ║>>> length: 78 Output: <<<║I never give 'em hel, I just tel the truth, and they think it's hel. ║>>> length: 75 ans = ║I never give 'em hel, I just tel the truth, and they think it's hel. ║ Input: <<<║ --- Harry S Truman ║>>> length: 78 Output: <<<║ - Hary S Truman ║>>> length: 23 ans = ║ - Hary S Truman ║ Input: <<<║ --- Harry S Truman ║>>> length: 78 Output: <<<║ - Hary S Truman ║>>> length: 23 ans = ║ - Hary S Truman ║ Input: <<<║ --- Harry S Truman ║>>> length: 78 Output: <<<║ - Hary S Truman ║>>> length: 23 ans = ║ - Hary S Truman ║ PASSES 1 out of 1 test
Modula-2
<lang modula2>MODULE StrCollapse; FROM InOut IMPORT WriteString, WriteCard, WriteLn; FROM Strings IMPORT Length;
(* Collapse a string *) PROCEDURE Collapse(in: ARRAY OF CHAR; VAR out: ARRAY OF CHAR);
VAR i, o: CARDINAL;
BEGIN
i := 0; o := 0; WHILE (i < HIGH(in)) AND (in[i] # CHR(0)) DO IF (o = 0) OR (out[o-1] # in[i]) THEN out[o] := in[i]; INC(o); END; INC(i); END; out[o] := CHR(0);
END Collapse;
(* Display a string and collapse it as stated in the task *) PROCEDURE Task(s: ARRAY OF CHAR);
VAR buf: ARRAY [0..127] OF CHAR; PROCEDURE LengthAndBrackets(s: ARRAY OF CHAR); BEGIN WriteCard(Length(s), 2); WriteString(" <<<"); WriteString(s); WriteString(">>>"); WriteLn(); END LengthAndBrackets;
BEGIN
LengthAndBrackets(s); Collapse(s, buf); LengthAndBrackets(buf); WriteLn();
END Task;
BEGIN
Task(""); Task('"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln '); Task("..1111111111111111111111111111111111111111111111111111111111111117777888"); Task("I never give 'em hell, I just tell the truth, and they think it's hell. "); Task(" --- Harry S Truman ");
END StrCollapse.</lang>
- Output:
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 >>>
NetLogo
* Enter the code below into the Code Pane of NetLogo * On the Interface Pane, in the Command Center, type "demo" and hit enter.
<lang NetLogo> to-report split [ string ]
;; utility reporter to split a string into a list report n-values length string [ [ n ] -> item n string ]
end
to-report collapse [ string ]
;; reporter that actually does the collapse function ifelse ( string = "" ) [ report "" ] [ report reduce [ [ a b ] -> (word a ifelse-value last a != b [ b ] [ "" ] ) ] split string ]
end
to-report format [ string ]
;; reporter to format the output as required report ( word "<<<" string ">>> " length string )
end
to demo-collapse [ string ]
;; procedure to display the required output output-print format string output-print format collapse string output-print ""
end
to demo
;; procedure to perform the test cases foreach [ "" "\"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 " ] demo-collapse
end </lang>
- Output:
observer> demo <<<>>> 0 <<<>>> 0 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> 72 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> 70 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> 72 <<<.178>>> 4 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> 72 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> 69 <<< --- Harry S Truman >>> 72 <<< - Hary S Truman >>> 17
Nim
<lang Nim>import unicode, strformat
proc collapse(s: string) =
let original = s.toRunes echo fmt"Original: length = {original.len}, string = «««{s}»»»" var previous = Rune(0) var collapsed: seq[Rune] for rune in original: if rune != previous: collapsed.add(rune) previous = rune echo fmt"Collapsed: length = {collapsed.len}, string = «««{collapsed}»»»" echo ""
const 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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌",]
for s in Strings:
s.collapse()</lang>
- Output:
Original: length = 0, string = «««»»» Collapsed: length = 0, string = «««»»» Original: length = 72, string = «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» Collapsed: length = 70, string = «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» Original: length = 72, string = «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» Collapsed: length = 4, string = «««.178»»» Original: length = 72, string = «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» Collapsed: length = 69, string = «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» Original: length = 72, string = ««« --- Harry S Truman »»» Collapsed: length = 17, string = ««« - Hary S Truman »»» Original: length = 80, string = «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» Collapsed: length = 77, string = «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» Original: length = 16, string = «««headmistressship»»» Collapsed: length = 14, string = «««headmistreship»»» Original: length = 8, string = «««aardvark»»» Collapsed: length = 7, string = «««ardvark»»» Original: length = 8, string = «««😍😀🙌💃😍😍😍🙌»»» Collapsed: length = 6, string = «««😍😀🙌💃😍🙌»»»
Perl
<lang perl>use strict; use warnings; use utf8; binmode STDOUT, ":utf8";
my @lines = split "\n", <<~'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 The American people have a right to know if their president is a crook. --- Richard Nixon AАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑ AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA STRINGS
for (@lines) {
my $squish = s/(.)\1+/$1/gr; printf "\nLength: %2d <<<%s>>>\nCollapsible: %s\nLength: %2d <<<%s>>>\n", length($_), $_, $_ ne $squish ? 'True' : 'False', length($squish), $squish
}</lang>
- Output:
Length: 0 <<<>>> Collapsible: False Length: 0 <<<>>> Length: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> Collapsible: True Length: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> Length: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> Collapsible: True Length: 4 <<<.178>>> Length: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> Collapsible: True Length: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> Length: 72 <<< --- Harry S Truman >>> Collapsible: True Length: 17 <<< - Hary S Truman >>> Length: 72 <<<The American people have a right to know if their president is a crook. >>> Collapsible: True Length: 71 <<<The American people have a right to know if their president is a crok. >>> Length: 72 <<< --- Richard Nixon >>> Collapsible: True Length: 17 <<< - Richard Nixon >>> Length: 120 <<<AАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑ>>> Collapsible: False Length: 120 <<<AАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑ>>> Length: 72 <<<AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA>>> Collapsible: True Length: 1 <<<A>>>
Phix
There is already a builtin we can abuse for this. The documentation of unique() [added for 0.8.1] states:
`If "PRESORTED" is specified, but s is not actually sorted, then only adjacent duplicates are removed.`
If you don't have builtins/punique.e to hand, you may want to take a quick look at squeeze() in
[[1]], but obviously w/o ch.
with javascript_semantics constant tests = {"", `"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 "}, fmt = """ length %2d input: <<<%s>>> length %2d output: <<<%s>>> """ for i=1 to length(tests) do string ti = tests[i], ci = unique(ti, "PRESORTED") printf(1,fmt,{length(ti),ti,length(ci),ci}) end for function collapsible(string t) -- sequence utf32 = utf8_to_utf32(t) -- maybe -- for i=2 to length(utf32) do -- """ -- if utf32[i]=utf32[i-1] then -- """ for i=2 to length(t) do if t[i]=t[i-1] then return true end if end for return false end function puts(1,"\nAs predicate: ") for i=1 to length(tests) do printf(1,"%t ",collapsible(tests[i])) end for puts(1,"\n")
- Output:
length 0 input: <<<>>> length 0 output: <<<>>> length 72 input: <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> length 70 output: <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> length 72 input: <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> length 4 output: <<<.178>>> length 72 input: <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> length 69 output: <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> length 72 input: <<< --- Harry S Truman >>> length 17 output: <<< - Hary S Truman >>> As predicate: false true true true true
PHP
<lang PHP><?php
function collapseString($string) {
$previousChar = null; $collapse = ; $charArray = preg_split('//u', $string, -1, PREG_SPLIT_NO_EMPTY); for ($i = 0 ; $i < count($charArray) ; $i++) { $currentChar = $charArray[$i]; if ($previousChar !== $currentChar) { $collapse .= $charArray[$i]; } $previousChar = $currentChar; } return $collapse;
}
function isCollapsible($string) {
return ($string !== collapseString($string));
}
$strings = array(
, 'another non colapsing string', '"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ', '..1111111111111111111111111111111111111111111111111111111111111117777888', "I never give 'em hell, I just tell the truth, and they think it's hell. ", ' --- Harry S Truman ', '0112223333444445555556666666777777778888888889999999999', "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", 'headmistressship', "😍😀🙌💃😍😍😍🙌",
);
foreach ($strings as $original) {
echo 'Original : <<<', $original, '>>> (len=', mb_strlen($original), ')', PHP_EOL; if (isCollapsible($original)) { $collapse = collapseString($original); echo 'Collapse : <<<', $collapse, '>>> (len=', mb_strlen($collapse), ')', PHP_EOL, PHP_EOL; } else { echo 'Collapse : string is not collapsing...', PHP_EOL, PHP_EOL; }
}</lang>
- Output:
Original : <<<>>> (len=0) Collapse : string is not collapsing... Original : <<<another non colapsing string>>> (len=28) Collapse : string is not collapsing... Original : <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> (len=72) Collapse : <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> (len=70) Original : <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> (len=72) Collapse : <<<.178>>> (len=4) Original : <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> (len=72) Collapse : <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> (len=69) Original : <<< --- Harry S Truman >>> (len=72) Collapse : <<< - Hary S Truman >>> (len=17) Original : <<<0112223333444445555556666666777777778888888889999999999>>> (len=55) Collapse : <<<0123456789>>> (len=10) Original : <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> (len=80) Collapse : <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> (len=77) Original : <<<headmistressship>>> (len=16) Collapse : <<<headmistreship>>> (len=14) Original : <<<😍😀🙌💃😍😍😍🙌>>> (len=8) Collapse : <<<😍😀🙌💃😍🙌>>> (len=6)
PL/M
Because of the limited character set supported by the PL/M-80 compiler,
uppercase letters have been substituted for lowercase letters,
the question mark for the period,
and the single quotation mark for the double quotation mark.
This has no other effect on the output.
While it would be possible to write the ASCII values as numbers, this would make the code less clear.
The COLLAPSE
procedure compares bytes and would be fine with any 8-bit input.
<lang plm>100H: BDOS: PROCEDURE (FN, ARG); DECLARE FN BYTE, ARG ADDRESS; GO TO 5; END BDOS; EXIT: PROCEDURE; CALL BDOS(0,0); END EXIT; PRINT: PROCEDURE (S); DECLARE S ADDRESS; CALL BDOS(9, S); END PRINT;
/* PRINT NUMBER */ PRINT$NUMBER: PROCEDURE (N);
DECLARE S (6) BYTE INITIAL ('.....$'); DECLARE (N, P) ADDRESS, C BASED P BYTE; P = .S(5);
DIGIT:
P = P - 1; C = N MOD 10 + '0'; N = N / 10; IF N > 0 THEN GO TO DIGIT; CALL PRINT(P);
END PRINT$NUMBER;
/* STRING LENGTH */ STR$LEN: PROCEDURE (STR) ADDRESS;
DECLARE (STR, I) ADDRESS, S BASED STR BYTE; I = 0; DO WHILE S(I) <> '$'; I = I + 1; END; RETURN I;
END STR$LEN;
/* COLLAPSE */ COLLAPSE: PROCEDURE (IN, OUT);
DECLARE (IN, OUT) ADDRESS, (I BASED IN, O BASED OUT, C) BYTE; C = I; DO WHILE C <> '$'; IN = IN + 1; IF I <> C THEN DO; O = C; OUT = OUT + 1; C = I; END; END; O = '$';
END COLLAPSE;
/* PRINT STRING AND LENGTH WITH BRACKETS */ PRINT$BRACKETS: PROCEDURE (S);
DECLARE S ADDRESS; CALL PRINT$NUMBER(STR$LEN(S)); CALL PRINT(.' <<<$'); CALL PRINT(S); CALL PRINT(.('>>>',13,10,'$'));
END PRINT$BRACKETS;
/* GIVEN A STRING, PRINT IT AND ITS COLLAPSED FORM */ SHOW: PROCEDURE (S);
DECLARE S ADDRESS, BUFFER (256) BYTE; CALL COLLAPSE(S, .BUFFER); CALL PRINT$BRACKETS(S); CALL PRINT$BRACKETS(.BUFFER); CALL PRINT(.(13,10,'$'));
END SHOW;
/* STRINGS FROM THE TASK */ DECLARE X (5) ADDRESS; X(0)=.'$'; X(1)=.(IF I WERE TWO-FACED, WOULD I BE WEARING ',
'THIS ONE. --- ABRAHAM LINCOLN $');
X(2)=.('..111111111111111111111111111111111111111',
'1111111111111111111111117777888$');
X(3)=.('I NEVER GIVE EM HELL, I JUST TELL THE TR',
'UTH, AND THEY THINK ITS HELL. $');
X(4)=.(' ',
' --- HARRY S TRUMAN $');
DECLARE I BYTE; DO I=0 TO LAST(X);
CALL SHOW(X(I));
END; CALL EXIT; EOF </lang>
- Output:
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 >>>
Prolog
<lang prolog>collapse_( [], [] ). collapse_( [A], [A] ). collapse_( [A,A|T], R ) :- collapse_( [A|T], R ). collapse_( [A,B|T], [A|R] ) :- dif( A, B ), collapse_( [B|T], R ).
collapse( Str, Collapsed ) :-
string_chars( Str, Chars ), collapse_( Chars, Result ), string_chars( Collapsed, Result ).</lang>
- Output:
?- collapse("122333444455555666666777777788888888999999999", New). New = "123456789" . ?- collapse("", New). New = "" . ?- collapse("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ", New). New = "\"If I were two-faced, would I be wearing this one?\" - Abraham Lincoln " . ?- collapse("..1111111111111111111111111111111111111111111111111111111111111117777888", New). New = ".178" . ?- collapse("I never give 'em hell, I just tell the truth, and they think it's hell. ", New). New = "I never give 'em hel, I just tel the truth, and they think it's hel. " . ?- collapse(" --- Harry S Truman ", New). New = " - Hary S Truman " . ?- collapse("The better the 4-wheel drive, the further you'll be from help when ya get stuck!", New). New = "The beter the 4-whel drive, the further you'l be from help when ya get stuck!" . 33 ?- collapse("headmistressship", New). New = "headmistreship" .
To determine if a string is collapsed or not, query if the result string is the same as the starting string. eg:
35 ?- S = "122333444455555666666777777788888888999999999", collapse(S,S). false. 37 ?- S = "123456789", collapse(S,S). S = "123456789" .
PureBasic
<lang PureBasic>EnableExplicit DataSection
STR1: Data.s "" STR2: Data.s "'If I were two-faced, would I be wearing this one?' --- Abraham Lincoln " STR3: Data.s "..1111111111111111111111111111111111111111111111111111111111111117777888" STR4: Data.s "I never give 'em hell, I just tell the truth, and they think it's hell. " STR5: Data.s " --- Harry S Truman "
EndDataSection
Procedure.s collapse(txt$)
Define *c.Character=@txt$, last.c=0, result$ While *c\c If *c\c<>last result$+Chr(*c\c) last=*c\c EndIf *c+SizeOf(Character) Wend ProcedureReturn result$
EndProcedure
OpenConsole("") Define *p_data=?STR1, buf$ While *p_data<=?STR4+StringByteLength(PeekS(?STR4))+2
buf$=PeekS(*p_data) PrintN("Before collapse: «««"+buf$+"»»» (length: "+Str(Len(buf$))+")") buf$=collapse(PeekS(*p_data)) PrintN("After collapse: «««"+buf$+~"»»» (length: "+Str(Len(buf$))+~")\n") *p_data+StringByteLength(PeekS(*p_data))+2
Wend Input()</lang>
- Output:
Before collapse: «««»»» (length: 0) After collapse: «««»»» (length: 0) Before collapse: «««'If I were two-faced, would I be wearing this one?' --- Abraham Lincoln »»» (length: 72) After collapse: «««'If I were two-faced, would I be wearing this one?' - Abraham Lincoln »»» (length: 70) Before collapse: «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» (length: 72) After collapse: «««.178»»» (length: 4) Before collapse: «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» (length: 72) After collapse: «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» (length: 69) Before collapse: ««« --- Harry S Truman »»» (length: 72) After collapse: ««« - Hary S Truman »»» (length: 17)
Python
<lang python>from itertools import groupby
def collapser(txt):
return .join(item for item, grp in groupby(txt))
if __name__ == '__main__':
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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌", ] for txt in strings: this = "Original" print(f"\n{this:14} Size: {len(txt)} «««{txt}»»»" ) this = "Collapsed" sqz = collapser(txt) print(f"{this:>14} Size: {len(sqz)} «««{sqz}»»»" )</lang>
- Output:
Original Size: 0 «««»»» Collapsed Size: 0 «««»»» Original Size: 72 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» Collapsed Size: 70 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» Original Size: 72 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» Collapsed Size: 4 «««.178»»» Original Size: 72 «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» Collapsed Size: 69 «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» Original Size: 72 ««« --- Harry S Truman »»» Collapsed Size: 17 ««« - Hary S Truman »»» Original Size: 80 «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» Collapsed Size: 77 «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» Original Size: 16 «««headmistressship»»» Collapsed Size: 14 «««headmistreship»»» Original Size: 8 «««aardvark»»» Collapsed Size: 7 «««ardvark»»» Original Size: 8 «««😍😀🙌💃😍😍😍🙌»»» Collapsed Size: 6 «««😍😀🙌💃😍🙌»»»
and for the missing predicate, foregrounded in the task title, and already forgotten in the listing of tests:
<lang python>Determining if a string is collapsible
from operator import eq
- isCollapsible :: String -> Bool
def isCollapsible(s):
True if s contains any consecutively repeated characters. return False if 2 > len(s) else ( any(map(eq, s, s[1:])) )
- ------------------------- TEST --------------------------
- main :: IO ()
def main():
Determining whether each string is collapsible xs = [ "", '"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", "😍😀🙌💃😍😍😍🙌", "abcdefghijklmnopqrstuvwxyz" ] print([ isCollapsible(x) for x in xs ])
- MAIN ---
if __name__ == '__main__':
main()</lang>
- Output:
[False, True, True, True, True, True, True, True, True, False]
Quackery
<lang Quackery> [ false -1 rot
witheach [ 2dup = iff [ drop dip not conclude ] else nip ] drop ] is collapsible ( $ --> b ) [ [] -1 rot witheach [ 2dup = iff drop else [ nip dup dip join ] ] drop ] is collapse ( $ --> $ )
[ dup collapsible iff [ dup collapse swap 2 ] else [ say "(Not collapsible.)" cr 1 ] times [ say "<<<" dup echo$ say ">>>" cr say " Length: " size echo say " characters" cr cr ] cr ] is task ( $ --> )
$ "" task $ '"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln ' task $ "..1111111111111111111111111111111111111111111111111111111111111117777888" task $ "I never give 'em hell, I just tell the truth, and they think it's hell. " task $ " --- Harry S Truman " task</lang>
- Output:
(Not collapsible.) <<<>>> Length: 0 characters <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> Length: 72 characters <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> Length: 70 characters <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> Length: 72 characters <<<.178>>> Length: 4 characters <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> Length: 72 characters <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> Length: 69 characters <<< --- Harry S Truman >>> Length: 72 characters <<< - Hary S Truman >>> Length: 17 characters
R
<lang R>collapse_string <- function(string){
str_iterable <- strsplit(string, "")1 message(paste0("Original String: ", "<<<", string, ">>>\n", "Length: ", length(str_iterable))) detect <- rep(TRUE, length(str_iterable)) for(i in 2:length(str_iterable)){ if(length(str_iterable)==0) break if(str_iterable[i] == str_iterable[i-1]) detect[i] <- FALSE } collapsed_string <- paste(str_iterable[detect],collapse = "") message(paste0("Collapsed string: ", "<<<",collapsed_string, ">>>\n", "Length: ", length(str_iterable[detect])), "\n")
}
test_strings <- c(
"", "'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", "Ciao Mamma, guarda come mi diverto!!"
)
for(test in test_strings){
collapse_string(test)
}
</lang>
- Output:
Original String: <<<>>> Length: 0 Collapsed string: <<<>>> Length: 0 Original String: <<<'If I were two-faced, would I be wearing this one?' --- Abraham Lincoln >>> Length: 72 Collapsed string: <<<'If I were two-faced, would I be wearing this one?' - Abraham Lincoln >>> Length: 70 Original String: <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> Length: 72 Collapsed string: <<<.178>>> Length: 4 Original String: <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> Length: 72 Collapsed string: <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> Length: 69 Original String: <<< --- Harry S Truman >>> Length: 72 Collapsed string: <<< - Hary S Truman >>> Length: 17 Original String: <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> Length: 80 Collapsed string: <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> Length: 77 Original String: <<<headmistressship>>> Length: 16 Collapsed string: <<<headmistreship>>> Length: 14 Original String: <<<aardvark>>> Length: 8 Collapsed string: <<<ardvark>>> Length: 7 Original String: <<<Ciao Mamma, guarda come mi diverto!!>>> Length: 36 Collapsed string: <<<Ciao Mama, guarda come mi diverto!>>> Length: 34
Racket
<lang Racket>#lang racket
(define (collapse text)
(if (< (string-length text) 2) text (string-append (if (equal? (substring text 0 1) (substring text 1 2)) "" (substring text 0 1)) (collapse (substring text 1)))))
- Test cases
(define tcs
'("" "\"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 ([text tcs])
(let ([collapsed (collapse text)]) (display (format "Original (size ~a): «««~a»»»\nCollapsed (size ~a): «««~a»»»\n\n" (string-length text) text (string-length collapsed) collapsed))))
</lang>
- Output:
Original (size 0): «««»»» Collapsed (size 0): «««»»» Original (size 72): «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» Collapsed (size 70): «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» Original (size 72): «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» Collapsed (size 4): «««.178»»» Original (size 72): «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» Collapsed (size 69): «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» Original (size 72): ««« --- Harry S Truman »»» Collapsed (size 17): ««« - Hary S Truman »»» Original (size 80): «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» Collapsed (size 77): «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» Original (size 16): «««headmistressship»»» Collapsed (size 14): «««headmistreship»»» Original (size 8): «««aardvark»»» Collapsed (size 7): «««ardvark»»» Original (size 8): «««😍😀🙌💃😍😍😍🙌»»» Collapsed (size 6): «««😍😀🙌💃😍🙌»»»
Raku
(formerly Perl 6)
Technically, the task is asking for a boolean. "Determine if a string is collapsible" is answerable with True/False, so return a boolean as well.
<lang perl6>map {
my $squish = .comb.squish.join; printf "\nLength: %2d <<<%s>>>\nCollapsible: %s\nLength: %2d <<<%s>>>\n", .chars, $_, .chars != $squish.chars, $squish.chars, $squish
}, lines
q:to/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 The American people have a right to know if their president is a crook. --- Richard Nixon AАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑ AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA STRINGS
</lang>
- Output:
Length: 0 <<<>>> Collapsible: False Length: 0 <<<>>> Length: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> Collapsible: True Length: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> Length: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> Collapsible: True Length: 4 <<<.178>>> Length: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> Collapsible: True Length: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> Length: 72 <<< --- Harry S Truman >>> Collapsible: True Length: 17 <<< - Hary S Truman >>> Length: 72 <<<The American people have a right to know if their president is a crook. >>> Collapsible: True Length: 71 <<<The American people have a right to know if their president is a crok. >>> Length: 72 <<< --- Richard Nixon >>> Collapsible: True Length: 17 <<< - Richard Nixon >>> Length: 72 <<<AАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑ>>> Collapsible: False Length: 72 <<<AАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑAАΑ>>> Length: 72 <<<AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA>>> Collapsible: True Length: 1 <<<A>>>
REXX
<lang rexx>/*REXX program "collapses" all immediately repeated characters in a string (or strings).*/ @.= /*define a default for the @. array. */ parse arg x /*obtain optional argument from the CL.*/ if x\= then @.1= x /*if user specified an arg, use that. */
else do; @.1= @.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 ' end
do j=1; L= length(@.j) /*obtain the length of an array element*/ say copies('═', 105) /*show a separator line between outputs*/ if j>1 & L==0 then leave /*if arg is null and J>1, then leave. */ new= collapse(@.j) say 'string' word("isn't is",1+collapsible) 'collapsible' /*display semaphore value*/ say ' length='right(L, 3) " input=«««" || @.j || '»»»' w= length(new) say ' length='right(w, 3) " output=«««" || new || '»»»' end /*j*/
exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ collapse: procedure expose collapsible; parse arg y 1 $ 2 /*get the arg; get 1st char. */
do k=2 to length(y) /*traipse through almost all the chars.*/ _= substr(y, k, 1) /*pick a character from Y (1st arg). */ if _==right($, 1) then iterate /*Is this the same character? Skip it.*/ $= $ || _ /*append the character, it's different.*/ end /*j*/ collapsible= y\==$; return $ /*set boolean to true if collapsible.*/</lang>
- output when using the internal default inputs:
═════════════════════════════════════════════════════════════════════════════════════════════════════════ string isn't collapsible length= 0 input=«««»»» length= 0 output=«««»»» ═════════════════════════════════════════════════════════════════════════════════════════════════════════ string is collapsible length= 72 input=«««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» length= 70 output=«««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» ═════════════════════════════════════════════════════════════════════════════════════════════════════════ string is collapsible length= 72 input=«««..1111111111111111111111111111111111111111111111111111111111111117777888»»» length= 4 output=«««.178»»» ═════════════════════════════════════════════════════════════════════════════════════════════════════════ string is collapsible length= 72 input=«««I never give 'em hell, I just tell the truth, and they think it's hell. »»» length= 69 output=«««I never give 'em hel, I just tel the truth, and they think it's hel. »»» ═════════════════════════════════════════════════════════════════════════════════════════════════════════ string is collapsible length= 72 input=««« --- Harry S Truman »»» length= 17 output=««« - Hary S Truman »»» ═════════════════════════════════════════════════════════════════════════════════════════════════════════
Ring
<lang ring> load "stdlib.ring"
see "working..." + nl + nl str = ["The better the 4-wheel drive, the further you'll be from help when ya get stuck!",
"I never give 'em hell, I just tell the truth, and they think it's hell.", "..1111111111111111111111111111111111111111111111111111111111111117777888"]
strsave = str for n = 1 to len(str)
for m = 1 to len(str[n])-1 if substr(str[n],m,1) = substr(str[n],m+1,1) str[n] = left(str[n],m) + right(str[n],len(str[n])-m-1) for p = len(str[n]) to 2 step -1 if substr(str[n],p,1) = substr(str[n],p-1,1) str[n] = left(str[n],p-1) + right(str[n],len(str[n])-p) ok next ok next
next
for n = 1 to len(str)
see "" + len(strsave[n]) + "«««" + strsave[n] + "»»»" + nl see "" + len(str[n]) + "«««" + str[n] + "»»»" + nl + nl
next
see "done..." + nl </lang> Output:
working... 80«««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» 77«««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» 71«««I never give 'em hell, I just tell the truth, and they think it's hell.»»» 68«««I never give 'em hel, I just tel the truth, and they think it's hel.»»» 72«««..1111111111111111111111111111111111111111111111111111111111111117777888»»» 4«««.178»»» done...
Ruby
This is built in since at least a decade under the method name 'squeeze'. squeeze(" ") would only squeeze spaces. <lang ruby>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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌",]
strings.each do |str|
puts "«««#{str}»»» (size #{str.size})" ssq = str.squeeze puts "«««#{ssq}»»» (size #{ssq.size})" puts
end </lang>
- Output:
«««»»» (size 0) «««»»» (size 0) «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» (size 72) «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» (size 70) «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» (size 72) «««.178»»» (size 4) «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» (size 72) «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» (size 69) ««« --- Harry S Truman »»» (size 72) ««« - Hary S Truman »»» (size 17) «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» (size 80) «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» (size 77) «««headmistressship»»» (size 16) «««headmistreship»»» (size 14) «««aardvark»»» (size 8) «««ardvark»»» (size 7) «««😍😀🙌💃😍😍😍🙌»»» (size 8) «««😍😀🙌💃😍🙌»»» (size 6)
Rust
<lang rust>fn collapse_string(val: &str) -> String {
let mut output = String::new(); let mut chars = val.chars().peekable();
while let Some(c) = chars.next() { while let Some(&b) = chars.peek() { if b == c { chars.next(); } else { break; } }
output.push(c); }
output
}
fn main() {
let tests = [ "122333444455555666666777777788888888999999999", "", "\"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", ];
for s in &tests { println!("Old: {:>3} <<<{}>>>", s.len(), s); let collapsed = collapse_string(s); println!("New: {:>3} <<<{}>>>", collapsed.len(), collapsed);
println!(); }
}</lang>
- Output:
Old: 45 <<<122333444455555666666777777788888888999999999>>> New: 9 <<<123456789>>> Old: 0 <<<>>> New: 0 <<<>>> Old: 72 <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> New: 70 <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> Old: 72 <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> New: 4 <<<.178>>> Old: 72 <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> New: 69 <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> Old: 72 <<< --- Harry S Truman >>> New: 17 <<< - Hary S Truman >>> Old: 80 <<<The better the 4-wheel drive, the further you'll be from help when ya get stuck!>>> New: 77 <<<The beter the 4-whel drive, the further you'l be from help when ya get stuck!>>> Old: 16 <<<headmistressship>>> New: 14 <<<headmistreship>>>
Scala
Pure imperative programming 😃
<lang Scala>object CollapsibleString {
/**Collapse a string (if possible)*/ def collapseString (s : String) : String = { var res = s var isOver = false var i = 0 if(res.size == 0) res else while(!isOver){ if(res(i) == res(i+1)){ res = res.take(i) ++ res.drop(i+1) i-=1 } i+=1 if(i==res.size-1) isOver = true } res }
/**Check if a string is collapsible*/ def isCollapsible (s : String) : Boolean = collapseString(s).length != s.length
/**Display results as asked in the task*/ def reportResults (s : String) : String = { val sCollapsed = collapseString(s) val originalRes = "ORIGINAL : length = " + s.length() + ", string = «««" + s + "»»»" val collapsedRes = "COLLAPSED : length = " + sCollapsed.length() + ", string = «««" + sCollapsed + "»»»" //In order to avoid useless computations, the function isCollapsible isn't called if(s.length != sCollapsed.length) originalRes + "\n" + collapsedRes + "\n" + "This string IS collapsible !" else originalRes + "\n" + collapsedRes + "\n" + "This string is NOT collapsible !" }
def main(args: Array[String]): Unit = { println(reportResults("")) println("------------") println(reportResults("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ")) println("------------") println(reportResults("..1111111111111111111111111111111111111111111111111111111111111117777888")) println("------------") println(reportResults("I never give 'em hell, I just tell the truth, and they think it's hell. ")) println("------------") println(reportResults(" --- Harry S Truman ")) println("------------") println(reportResults("The better the 4-wheel drive, the further you'll be from help when ya get stuck!")) println("------------") println(reportResults("headmistressship")) println("------------") println(reportResults("aardvark")) }
}</lang>
- Output:
ORIGINAL : length = 0, string = «««»»» COLLAPSED : length = 0, string = «««»»» This string is NOT collapsible ! ------------ ORIGINAL : length = 72, string = «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» COLLAPSED : length = 70, string = «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» This string IS collapsible ! ------------ ORIGINAL : length = 72, string = «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» COLLAPSED : length = 4, string = «««.178»»» This string IS collapsible ! ------------ ORIGINAL : length = 72, string = «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» COLLAPSED : length = 69, string = «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» This string IS collapsible ! ------------ ORIGINAL : length = 72, string = ««« --- Harry S Truman »»» COLLAPSED : length = 17, string = ««« - Hary S Truman »»» This string IS collapsible ! ------------ ORIGINAL : length = 80, string = «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» COLLAPSED : length = 77, string = «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» This string IS collapsible ! ------------ ORIGINAL : length = 16, string = «««headmistressship»»» COLLAPSED : length = 14, string = «««headmistreship»»» This string IS collapsible ! ------------ ORIGINAL : length = 8, string = «««aardvark»»» COLLAPSED : length = 7, string = «««ardvark»»» This string IS collapsible !
Sidef
<lang ruby>func squeeze(str) {
str.gsub(/(.)\1+/, {|s1| s1 })
}
var 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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌"]
strings.each {|str|
var ssq = squeeze(str) say "«««#{str}»»» (length: #{str.len})" say "«««#{ssq}»»» (length: #{ssq.len})\n"
}</lang>
- Output:
«««»»» (length: 0) «««»»» (length: 0) «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» (length: 72) «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» (length: 70) «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» (length: 72) «««.178»»» (length: 4) «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» (length: 72) «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» (length: 69) ««« --- Harry S Truman »»» (length: 72) ««« - Hary S Truman »»» (length: 17) «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» (length: 80) «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» (length: 77) «««headmistressship»»» (length: 16) «««headmistreship»»» (length: 14) «««aardvark»»» (length: 8) «««ardvark»»» (length: 7) «««😍😀🙌💃😍😍😍🙌»»» (length: 8) «««😍😀🙌💃😍🙌»»» (length: 6)
Smalltalk
<lang smalltalk>#(
'The better the 4-wheel drive, the further youll be from help when ya get stuck!' 'headmistressship' 'aardvark' '😍😀🙌💃😍😍😍🙌'
) do:[:eachWord |
|shortened|
shortened := String streamContents:[:out | eachWord inject:nil into:[:prev :this | prev ~= this ifTrue:[out nextPut:this]. this ] ]. Transcript showCR:( eachWord,'(length:',eachWord size,')' ); showCR:( shortened,'(length:',shortened size,')' ).
]</lang>
- Output:
The better the 4-wheel drive, the further you'll be from help when ya get stuck!(length:80) The beter the 4-whel drive, the further you'l be from help when ya get stuck!(length:77) headmistressship(length:16) headmistreship(length:14) aardvark(length:8) ardvark(length:7) 😍😀🙌💃😍😍😍🙌(length:8) 😍😀🙌💃😍🙌(length:6)
Swift
<lang Swift>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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌" ]
let collapsedStrings = strings.map { $0.replacingOccurrences( of: #"(.)\1*"#, with: "$1", options: .regularExpression)}
for (original, collapsed) in zip(strings, collapsedStrings) { print (String(format: "%03d «%@»\n%03d «%@»\n", original.count, original, collapsed.count, collapsed)) }</lang>
- Output:
000 «» 000 «» 072 «"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln » 070 «"If I were two-faced, would I be wearing this one?" - Abraham Lincoln » 072 «..1111111111111111111111111111111111111111111111111111111111111117777888» 004 «.178» 072 «I never give 'em hell, I just tell the truth, and they think it's hell. » 069 «I never give 'em hel, I just tel the truth, and they think it's hel. » 072 « --- Harry S Truman » 017 « - Hary S Truman » 080 «The better the 4-wheel drive, the further you'll be from help when ya get stuck!» 077 «The beter the 4-whel drive, the further you'l be from help when ya get stuck!» 016 «headmistressship» 014 «headmistreship» 008 «aardvark» 007 «ardvark» 008 «😍😀🙌💃😍😍😍🙌» 006 «😍😀🙌💃😍🙌»
Tcl
Please note the ;# ' comments, there appears to be a syntax hightlighting bug with RC <lang tcl>set test {
{} {"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}
}
foreach {str} $test {
# Uses regexp lookbehind to detect repeated characters set sub [regsub -all {(.)(\1+)} $str {\1}]
# Output puts [format "Original (length %3d): %s" [string length $str] $str] puts [format "Subbed (length %3d): %s" [string length $sub] $sub] puts ----------------------
} </lang>
- Output:
Original (length 0): Subbed (length 0): ---------------------- Original (length 72): "If I were two-faced, would I be wearing this one?" --- Abraham Lincoln Subbed (length 70): "If I were two-faced, would I be wearing this one?" - Abraham Lincoln ---------------------- Original (length 72): ..1111111111111111111111111111111111111111111111111111111111111117777888 Subbed (length 4): .178 ---------------------- Original (length 72): I never give 'em hell, I just tell the truth, and they think it's hell. Subbed (length 69): I never give 'em hel, I just tel the truth, and they think it's hel. ---------------------- Original (length 72): --- Harry S Truman Subbed (length 17): - Hary S Truman ---------------------- Original (length 80): The better the 4-wheel drive, the further you'll be from help when ya get stuck! Subbed (length 77): The beter the 4-whel drive, the further you'l be from help when ya get stuck! ---------------------- Original (length 16): headmistressship Subbed (length 14): headmistreship ----------------------
Visual Basic .NET
<lang vbnet>Module Module1
Function Collapse(s As String) As String If String.IsNullOrEmpty(s) Then Return "" End If Return s(0) + New String(Enumerable.Range(1, s.Length - 1).Where(Function(i) s(i) <> s(i - 1)).Select(Function(i) s(i)).ToArray) End Function
Sub Main() Dim input() = { "", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", ControlChars.Quote + "If I were two-faced, would I be wearing this one?" + ControlChars.Quote + " --- Abraham Lincoln ", "..1111111111111111111111111111111111111111111111111111111111111117777888", "I never give 'em hell, I just tell the truth, and they think it's hell. ", " --- Harry S Truman " } For Each s In input Console.WriteLine($"old: {s.Length} «««{s}»»»") Dim c = Collapse(s) Console.WriteLine($"new: {c.Length} «««{c}»»»") Next End Sub
End Module</lang>
- Output:
old: 0 «««»»» new: 0 «««»»» old: 80 «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» new: 77 «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» old: 16 «««headmistressship»»» new: 14 «««headmistreship»»» old: 72 «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» new: 70 «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» old: 72 «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» new: 4 «««.178»»» old: 72 «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» new: 69 «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» old: 72 ««« --- Harry S Truman »»» new: 17 ««« - Hary S Truman »»»
VBA
Function : <lang vb>Function Collapse(strIn As String) As String Dim i As Long, strOut As String
If Len(strIn) > 0 Then strOut = Mid$(strIn, 1, 1) For i = 2 To Len(strIn) If Mid$(strIn, i, 1) <> Mid$(strIn, i - 1, 1) Then strOut = strOut & Mid$(strIn, i, 1) End If Next i End If Collapse = strOut
End Function</lang> To Call : <lang vb>Sub CallCollapse() Dim S As String
S = vbNullString Debug.Print "String : <<<" & S & ">>>", "Lenght : " & Len(S) Debug.Print "Collapsed : <<<" & Collapse(S) & ">>>", "Lenght : " & Len(Collapse(S)) S = """If I were two-faced, would I be wearing this one?"" --- Abraham Lincoln " Debug.Print "String : <<<" & S & ">>>", "Lenght : " & Len(S) Debug.Print "Collapsed : <<<" & Collapse(S) & ">>>", "Lenght : " & Len(Collapse(S)) S = "..1111111111111111111111111111111111111111111111111111111111111117777888" Debug.Print "String : <<<" & S & ">>>", "Lenght : " & Len(S) Debug.Print "Collapsed : <<<" & Collapse(S) & ">>>", "Lenght : " & Len(Collapse(S)) S = "I never give 'em hell, I just tell the truth, and they think it's hell. " Debug.Print "String : <<<" & S & ">>>", "Lenght : " & Len(S) Debug.Print "Collapsed : <<<" & Collapse(S) & ">>>", "Lenght : " & Len(Collapse(S)) S = " --- Harry S Truman " Debug.Print "String : <<<" & S & ">>>", "Lenght : " & Len(S) Debug.Print "Collapsed : <<<" & Collapse(S) & ">>>", "Lenght : " & Len(Collapse(S))
End Sub</lang>
- Output:
String : <<<>>> Lenght : 0 Collapsed : <<<>>> Lenght : 0 String : <<<"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln >>> Lenght : 72 Collapsed : <<<"If I were two-faced, would I be wearing this one?" - Abraham Lincoln >>> Lenght : 70 String : <<<..1111111111111111111111111111111111111111111111111111111111111117777888>>> Lenght : 72 Collapsed : <<<.178>>> Lenght : 4 String : <<<I never give 'em hell, I just tell the truth, and they think it's hell. >>> Lenght : 72 Collapsed : <<<I never give 'em hel, I just tel the truth, and they think it's hel. >>> Lenght : 69 String : <<< --- Harry S Truman >>> Lenght : 72 Collapsed : <<< - Hary S Truman >>> Lenght : 17
Wren
<lang ecmascript>import "/fmt" for Fmt
// Returns collapsed string, original and new lengths in // unicode code points (not normalized). var collapse = Fn.new { |s|
var c = s.codePoints.toList var le = c.count if (le < 2) return [s, le, le] for (i in le-2..0) { if (c[i] == c[i+1]) c.removeAt(i) } var cc = c.reduce("") { |acc, cp| acc + String.fromCodePoint(cp) } return [cc, le, cc.count]
}
var 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 ", "The better the 4-wheel drive, the further you'll be from help when ya get stuck!", "headmistressship", "aardvark", "😍😀🙌💃😍😍😍🙌"
]
for (s in strings) {
var r = collapse.call(s) System.print("original : length = %(Fmt.d(2, r[1])), string = «««%(s)»»»") System.print("collapsed: length = %(Fmt.d(2, r[2])), string = «««%(r[0])»»»\n")
}</lang>
- Output:
original : length = 0, string = «««»»» collapsed: length = 0, string = «««»»» original : length = 72, string = «««"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln »»» collapsed: length = 70, string = «««"If I were two-faced, would I be wearing this one?" - Abraham Lincoln »»» original : length = 72, string = «««..1111111111111111111111111111111111111111111111111111111111111117777888»»» collapsed: length = 4, string = «««.178»»» original : length = 72, string = «««I never give 'em hell, I just tell the truth, and they think it's hell. »»» collapsed: length = 69, string = «««I never give 'em hel, I just tel the truth, and they think it's hel. »»» original : length = 72, string = ««« --- Harry S Truman »»» collapsed: length = 17, string = ««« - Hary S Truman »»» original : length = 80, string = «««The better the 4-wheel drive, the further you'll be from help when ya get stuck!»»» collapsed: length = 77, string = «««The beter the 4-whel drive, the further you'l be from help when ya get stuck!»»» original : length = 16, string = «««headmistressship»»» collapsed: length = 14, string = «««headmistreship»»» original : length = 8, string = «««aardvark»»» collapsed: length = 7, string = «««ardvark»»» original : length = 8, string = «««😍😀🙌💃😍😍😍🙌»»» collapsed: length = 6, string = «««😍😀🙌💃😍🙌»»»
zkl
<lang zkl>fcn collapsible(str){ // no Unicode
sink:=Sink(String); str.reduce('wrap(c1,c2){ if(c1!=c2) sink.write(c2); c2 },""); // prime with \0 cstr:=sink.close(); return(str.len()!=cstr.len(), cstr);
}</lang> <lang zkl>strings:= 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
The American people have a right to know if their president is a crook.
--- Richard Nixon
The better the 4-wheel drive, the further you'll be from help when ya get stuck! headmistressship aardvark^ .split("\n");
- <<<
foreach s in (strings){
println("Before: %3d >>>%s<<<".fmt(s.len(),s)); _,cstr:=collapsible(s); println("After: %3d >>>%s<<<\n".fmt(cstr.len(),cstr));
}</lang>
- Output:
Before: 0 >>><<< After: 0 >>><<< Before: 72 >>>"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln <<< After: 70 >>>"If I were two-faced, would I be wearing this one?" - Abraham Lincoln <<< Before: 72 >>>..1111111111111111111111111111111111111111111111111111111111111117777888<<< After: 4 >>>.178<<< Before: 72 >>>I never give 'em hell, I just tell the truth, and they think it's hell. <<< After: 69 >>>I never give 'em hel, I just tel the truth, and they think it's hel. <<< Before: 72 >>> --- Harry S Truman <<< After: 17 >>> - Hary S Truman <<< Before: 72 >>>The American people have a right to know if their president is a crook. <<< After: 71 >>>The American people have a right to know if their president is a crok. <<< Before: 72 >>> --- Richard Nixon <<< After: 17 >>> - Richard Nixon <<< Before: 80 >>>The better the 4-wheel drive, the further you'll be from help when ya get stuck!<<< After: 77 >>>The beter the 4-whel drive, the further you'l be from help when ya get stuck!<<< Before: 16 >>>headmistressship<<< After: 14 >>>headmistreship<<< Before: 8 >>>aardvark<<< After: 7 >>>ardvark<<<
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