my @typeset = ('P', 'K', 'L', 'G');
my $length = 10;
my @lchain = ();
strangemultiset($length, \@typeset, \@lchain);

exit 0;

sub strangemultiset
{
	my $len=$_[0];
	my @types=@{$_[1]};
	my @chain=@{$_[2]};
	my $ltype=shift(@types);
	my $var=$len - scalar(@chain) - scalar(@types);
	for(my $iter=1; $iter<=$var; ++$iter)
	{
	push(@chain, $ltype);
		if (scalar(@types) == 0)
		{
			if (scalar(@chain) == $len)
			{       # we have a valid set, print it.
				print join('.', @chain), "\n";
			}
		}
		else
		{
			strangemultiset($len, \@types, \@chain);
		}
	}
}