sub fbhp {
    my $string = shift;
    my $seperator = shift || '-';

    my @elements = split /$seperator/, $string;
    my @status;
    my $count = $#elements;
    push @status, 0 for (0..$count); #kann man sich auch sparen
    my @ret;

    for (my $i = 1; $i <= 2 ** $count; ++$i) {
        my $this = $elements[0];
        for (my $j = 0; $j < $count; ++$j) {
            $this .= $seperator if ($status[$j]);
            if ($i % 2 ** $j == 0) {
               $status[$j] = (++$status[$j]) % 2;
            }
            $this .= $elements[$j+1];
        }
        push @ret, $this;
    }
}