What is the minimum (and how to calculate it?) number of bits required to perfectly hash/map pawn occupancy with black and white pawns treated differently (meaning a position with black pawns and white pawns doesn't equal the same position with the colors inverted)?
-1st comment: a square is either occupied by a black pawn or a white pawn or is empty, so I guess? three states.
-2nd comment: Both cases.
-1st answer: by the way optimization is highly important.