#!/usr/bin/perl -w
use strict;
han('A','B','C',$ARGV[0]);
sub han{
    return if $_[3] <= 0;
    han($_[0],$_[2],$_[1],$_[3]-1);
    print "Move disc $_[3] from $_[0] to $_[2]\n";
    han($_[1],$_[0],$_[2],$_[3]-1);
}