#!/usr/bin/perl

use warnings;
use strict;

my $num = 1_002_345;

my $total = $num + 1000;

##</code><code>##

sub commify {
    my $text = reverse $_[0];
    $text =~ s/(\d\d\d)(?=\d)(?!\d*\.)/$1,/g;
    return scalar reverse $text;
}