I know this thread is pretty old, but I just read it and saw a way to improve the code. One thing you could do that should speed things up is to store the results in a hash. You can then avoid using uniq and you will only be doing the matching operation on pieces you haven't yet seen.
#!/usr/bin/perl -w use strict; my $line; my %count; while ( defined ( $line = <> ) ) { chomp $line; for my $a ( 1 .. length ( $line ) ) { for my $b ( 1 .. ( length ( $line ) + 1 - $a ) ) { my $out = substr ( $line, $a - 1, $b ); next unless $count{ $out }; # so you don't have to use uniq next if ( $count{ $out } = () = $line =~ /$out/g ) > 1; print "length: $b digits: $out quantity: $count{ $out }"; } } }
I just glanced through the other comments and saw some good points in there too, so if you're using this code make sure to take those into account as well. I didn't want to rewrite the whole thing, but just wanted to point out how the hash could be useful.

In reply to Re: Longest repeated string... by redEvo
in thread Longest repeated string... by Yzzyx

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