#build the tree
my $root = Tree::DAG_Node->new;
$root->attributes({
    original=>"permit ip any any",
    source=>['0.0.0.0/0'],
    destination=>['0.0.0.0/0']
});
foreach my $node (@node_list){
	my $location;
	$root->walk_down({
			callback => sub {
				my $this_node = shift;
				if (compare_nodes($node,$this_node)){
					$location = $this_node->address;
					1;
				}
				else{
					0;
				}
			}

    });
	$root->address($location)->add_daughter($node)
      if defined $root->address($location);
}