I originally went your way and tried to write an algorithm with different scores and it worked, but it didn't always fit perfectly into 16 moves. Then I thought, I needed a stable solution and I thought about creating an endgame table for this problem. And actually for me it was not trivial, finding the right algorithm and implementing it to make things work relatively fast is not an easy task, especially debugging caused a lot of pain given the number of possible states. All these attempts took quite a long time, I returned to this problem intermittently for 6 months, so for me it's 1kuy. By the way funny fact, if you look at other users' solutions, about half of the solutions have hardcoded tables.

looks resolved

Coming from other languages: this made my head explode. Well done!

Use spoiler flag next time, please.

Most parantheses are unneeded

Looks like you like golf :D

Both braincells were fully activated for sure.

You're not stupid, or maybe I'm stupid the exact same way. :P

Scala translation

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