I'm not drunk enough to fully understand the code, but the math called me.
Perl v5.18.0 required--this is only v5.14.2, stopped at q line 2.

:(

I feel left out, because your code does not run on my system (an up-to-date Debian Stable release), it seems all you do is use "say", which means you should change
use 5.018;
into
use v5.10;
And it runs for me too..

:)

Certainly interesting. Going beyond a mere wordcount.
You also may want to throw in a undef $/; to slurp in more than the first line (or did you plan to enhance the algorithm to seek inserted lines, a bit what diff does)?
You can also count the hash like this 

$F1{$_}++ for @F1;
$F1{$_}-- for @F2;

[download]

if equal it is 0, if positive, the second file was missing it (or one ocurrance), if negative... well.. And depending on the farness from 0 you can build your stats. Takes less mem too.

In reply to Re: File Similarity Concept by FreeBeerReekingMonk
in thread File Similarity Concept by ww

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