Beefy Boxes and Bandwidth Generously Provided by pair Networks
Do you know where your variables are?

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

I don't know if this will be as fast as pemungkah's approach, but the Perl regex engine builds a trie for alternations, so even quite large alternations (354K words in Moby file) are very fast. The big time sink is reading all the words and building the alternation string in the first place, but of course this could be done in a separate step and the resulting joined string saved to a file for later quick access. (Also note that the dictionary file I'm using has oddities such as 'words' like "d's" and "e's", and apparently every letter of the alphabet appears as a word.)

>perl -wMstrict -le "my $wordlist = shift // die 'no wordlist filename given'; open my $fh_wordlist, '<', $wordlist or die qq{opening '$wordlist': $!}; my $words = join '|', sort { length($b) <=> length($a) } map { chomp; $_; } <$fh_wordlist> ; close $fh_wordlist or die qq{closing '$wordlist': $!}; ;; my @lexicon = qw( no now know known unknown antidisestablishment husband wife husband's wife's xyzzy a ); for my $word (@lexicon) { my ($longest_at_end) = $word =~ m{ \B ($words) \z }xms; print qq{'$word' -> '$longest_at_end'}; } " ..\..\moby\mwords\354984si.ngl 'no' -> 'o' 'now' -> 'ow' 'know' -> 'now' 'known' -> 'own' 'unknown' -> 'known' 'antidisestablishment' -> 'disestablishment' 'husband' -> 'band' 'wife' -> 'ife' 'husband's' -> 'd's' 'wife's' -> 'e's' 'xyzzy' -> 'y' Use of uninitialized value $longest_at_end in concatenation (.) or str +ing at -e line 1. 'a' -> ''

In reply to Re: Longest String Matching by AnomalousMonk
in thread Longest String Matching by Dr Manhattan

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?

    What's my password?
    Create A New User
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others meditating upon the Monastery: (5)
    As of 2019-10-19 16:29 GMT
    Find Nodes?
      Voting Booth?