Longest palindromic substrings: Difference between revisions
Content deleted Content added
m added related tasks. |
m →{{header|REXX}}: shortened a long statement (line), add/changed comments and whitespace. |
||
Line 733: | Line 733: | ||
<lang rexx>/*REXX program finds and displays the longest palindromic string(s) in a given string. */ |
<lang rexx>/*REXX program finds and displays the longest palindromic string(s) in a given string. */ |
||
parse arg s /*obtain optional argument from the CL.*/ |
parse arg s /*obtain optional argument from the CL.*/ |
||
if s=='' |
if s==''|s=="," then s='babaccd rotator reverse forever several palindrome abaracadaraba' |
||
/* [↑] the case of strings is respected*/ |
/* [↑] the case of strings is respected*/ |
||
do i=1 for words(s); x= word(s, i) /*obtain a string to be examined. */ |
|||
L= length(x); m= 0 /*get the string's length; Set max len.*/ |
|||
do LL=2 for L-1 /*start with palindromes of length two.*/ |
|||
m= 0 |
|||
if find(1) then m= max(m, LL) /*Found a palindrome? Set M=new length*/ |
|||
end /*LL*/ |
|||
⚫ | |||
end /*LL*/ |
|||
call find 0 /*find all palindromes with length LL.*/ |
|||
⚫ | |||
⚫ | |||
call find . |
|||
⚫ | |||
⚫ | |||
do n=1 for words(@) /*show longest palindromic substrings. */ |
|||
⚫ | |||
say ' (length='LL") " word(@, n) /*display a " substring. */ |
|||
say |
end /*n*/; say; say /*display a two─blank separation fence.*/ |
||
end /*i*/ |
|||
end /*i*/ |
|||
exit 0 /*stick a fork in it, we're all done. */ |
exit 0 /*stick a fork in it, we're all done. */ |
||
/*──────────────────────────────────────────────────────────────────────────────────────*/ |
/*──────────────────────────────────────────────────────────────────────────────────────*/ |
||
find: parse arg short /*if SHORT==1, only find 1 palindrome.*/ |
find: parse arg short /*if SHORT==1, only find 1 palindrome.*/ |
||
@= /*initialize palindrome list to a null.*/ |
@= /*initialize palindrome list to a null.*/ |
||
do j=1 for L-LL+1; $= substr(x, j, LL) /*obtain a possible palindromic substr.*/ |
|||
if $\==reverse($) then iterate /*Not a palindrome? Then skip it.*/ |
|||
@= @ $ /*add a palindromic substring to a list*/ |
|||
if short then return 1 /*we have found one palindrome. */ |
|||
end /*j*/; return 0 /* " " " some palindrome(s). */</lang> |
|||
end /*j*/; return 0 /* " " some palindrome(s). */</lang> |
|||
{{out|output|text= when using the default input:}} |
{{out|output|text= when using the default input:}} |
||
<pre> |
<pre> |