#!/usr/bin/perl use strict; use warnings; use NetAddr::IP; # Beware large IP sets... print join("\n", map { $_->addr } sort map { new NetAddr::IP $_ } ), "\n"; __DATA__ 10.1.5.2 10.1.1.2 10.1.0.1 10.1.1.0 10.1.1.1 10.1.5.1