#!/usr/bin/perl

use strict;
use warnings;

use NAT::PTD;

my $filename = shift;

my $ptd = NAT::PTD->new($filename);

my %h;

$ptd->downtr(
             sub {
                 my ($w, $c, %t) = @_;
                 $h{$w} = join(", ", sort { $t{$b} <=> $t{$a} } keys %t);
             }
            );


for (sort keys %h) {
    print "$_ / $h{$_}\n";
}