Without addressing parallelization nor performing any benchmarks, here's naive implementation. Hopefully, fuzzy matching implemented and optimized in C is fast. Maybe, re-writing this with String::Approx instead of re::engine::TRE (subroutine call instead of Perl regexp engine overhead) would be faster. Re-visiting fuzzy string matching was fun :). Solution below was more readable/clear before I tried to get to (perceived, no tests) optimizations like dropping blocks, reversing loop, + remembering that to use a reference to substr result is efficient (no idea if it holds in this case), etc., but here's FWIW.

use strict; use warnings; use feature 'say'; use constant ERR => 1; use re::engine::TRE max_cost => ERR, cost_ins => -1, # no insertions cost_del => -1, # no deletions ; my $suffix_source = 'abbaba'; my $prefix_source = 'babbaaaa'; my $max_len = 0; $prefix_source =~ /^${ \substr $suffix_source, -$_ }/ and $max_len = $_ and last for reverse ERR + 1 .. length $suffix_source; say substr( $suffix_source, -$max_len ), ' ', substr( $prefix_source, 0, $max_len ) if $max_len; __END__ baba babb

Update: crude benchmarks (~200 chars strings, ~10 errors allowed) reveal that, for this task, both modules I mentioned are hugely (some 10s of times) slower than "classic" Perl implementation by tybalt89 :)


In reply to Re: Suffix-prefix matching done right by vr
in thread Suffix-prefix matching done right by baxy77bax

Title:
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, details, 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, summary, 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.