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Building on japhy's regex, this seems to work and it's fairly simple, though I haven't tested it's efficiency. It returns undef if there is no common substring.

Caveat: The strings mustn't contain nulls.

#! perl -slw use strict; sub lcs{ my $strings = join "\0", @_; my $lcs; for my $n ( 1 .. length $strings ) { my $re = "(.{$n})" . '.*\0.*\1' x ( @_ - 1 ); last unless $strings =~ $re; $lcs = $1 } return $lcs; } my @a = <DATA>; chomp @a; print "lcs: ", lcs( @a ); __DATA__ The quick brown fox jump over the lazy dog The quick brown fox jumps over the lazy jumps over the lazy dog The quick brown fox quick brown fox jumps over the lazy dog

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In reply to Re: finding longest common substring by BrowserUk
in thread finding longest common substring by revdiablo

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