I thought I had fixed this, seems not, can you tell me the quanity of the boxes left in the end with multiple solutions? are it just 4 or more then that? Either way, when you’re in such a situation any possible solution will be taken as a good solution, so you wont have to try many times. One try is enough. If you’re sure that there are two possibilities left at one spot, you can enter either of them and still get a good solution. If in the end it seems you chose wrong, then your assumption seemed false and there was only one possibility for that box.
I’ll look at it when I have the time, as I said I thought I’d fixed that annoying bug, seems I underestimated randomness :/
"The absence of rules is the enemy of art." ~Orson Wells
