use Data::Dumper;

#    1
#   / \
#  2   3
# / \
#4   5 


my ($root) = (@ARGV);

if (!$root) {
	$root = 1;
}
$ret = get_all_paths($root);
print Dumper($ret);

sub get_branches
{
	my ($i) = (@_);
	if ($i==1) {
		return [2, 3];
	}
	if ($i==2) {
		return [4, 5];
	}
	return [];
}

sub get_all_paths
{
	my ($root) = (@_);
	my @allroutes;
	my $branches;
	$branches = get_branches($root);
	if (@$branches == 0) { # we've reached the end/leaf node
		return [ [$root]];
	}
	foreach my $branch (@$branches) {
		my $partial_routes = get_all_paths($branch);
		foreach my $route (@$partial_routes) {
			my @newroute;
			push @newroute, $root;
			push @newroute, @$route;
			push @allroutes, \@newroute;
		}
	}
	return \@allroutes;
}