Now fixed.

You should read again the description!

But, thence, 16 would be [4, 3, 3, 3, 3] instead of the given [4, 4, 4, 4, 0].

Also, I cannot derive the split [4, 4, 4, 4, 0] given the rules. It breaks the rule 'the fifth part has the longest length'.

I think 6 would be [2,1,1,1,1] and 7 would be [2,2,1,1,1] and 11 would be [3,2,2,2,2] mainly driven by the restriction that the fifth portion be as long as possible but less than or equal to the other 4.

Maybe I thought I could use negative numbers...

Have you tried logging the inputs to the console so you can see them?

Same question abuot length equals 7 or 11

Feel free to contribute such test case :)

Thanks :)