could you give me some tricky tests please? i tried everything that came through my mind. Thanks.

I also experienced WA #29 (and WA #21 during attempts to fix it). IMHO, these tests have equal numbers in the end.

My data cases.

For WA29:
> 1 4
> 1 2 1 1

For WA21:
> 1 6
> 1 6 3 2 1 1

Increase your arrays length...