True, no hexadecimal numbers are accepted by that solution, Random Tests gives it every 3-4 attempt, try it.

Sorry for a probably silly question, but if the length of the first and second is 0 - should i just skip the rest, or return 0 ? Thanks in advance

There is no issue, there is a trick, very nice and shiny :)

God when I actually understood what was the trick, that was awesome, so cool when you see it :)
Great Kata

Thanks

Kind Regards

Michail

Backwards Dec values order ;)