#!/usr/bin/perl

use Compress::Zlib 'compress';

# Usage:   $arrayref = similarity( LIST)
# Returns: AoA reference to string similarity table for LIST
sub similarity {
    my (%single, @ret) = map {$_ => length compress $_} @_;
    for my $this (@_) {
        push @ret, [
            map {
               (length compress $this . $_)
                 / ($single{$this} + $single{$_})
            } @_ 
        ];
    }
    \@ret;
}

my @titles = (
    q(The Last Public Hanging In Old West Virginia - Flatt and Scruggs),
    q(Flatt_and_Scruggs__The_Last_Public_Hanging_In_Old_West_Virginia),
    q(Rainy Day Woman Number 12 and 35 - Flatt and Scruggs),
    q(Rainy Day Woman Number Twelve and Thirty-five - Bob Dylan),
);

my $results = similarity @titles;

for my $this (@$results) {
    print pack('A6' x @$this, map {sprintf '%4.3f', $_} @$this), $/;
}

__END__

0.529 0.715 0.784 0.841 
0.708 0.529 0.887 0.870 
0.784 0.863 0.536 0.748 
0.848 0.863 0.739 0.532