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Comment by staunch | Hacker News Reader

Easy job for a regex:

    while ($string =~ /((\w+)\w?(??{reverse $2}))/g) { print "$1\n"; }

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fuckin nice. now I feel like a doofus for using ruby, when I thought it was straightforward.

I've done it ruby this way:

    text.scan(/(.)(.)(.)(.)(\3)(\2)(\1)/)

That's pretty frail. It won't catch palindromes with an even number of letters (e.g. ababbaba) and it'll only find those of at most 7 characters. Granted, you can use those matches to work outwards and search for more, but I didn't think the general solution was all that hard.

Oddly enough, it didn't even occur to me to try a regex and I like using them quite a bit.

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