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bsamseth / Goldfish

Goldfish - Stockfish's very distant and not so bright cousin - a UCI chess engine
MIT License
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Use zero width window search in null move pruning #22

Closed bsamseth closed 5 years ago

bsamseth commented 5 years ago

In null move pruning, we only really care about a lower bound. If this exceeds beta, then great, we have a cutoff. The exact value in [alpha, beta] is not that important.

coveralls commented 5 years ago

Coverage Status

Coverage remained the same at 86.027% when pulling 59403541ee77a99da38f33f6e7ef112aaeba3ffe on null-move-pruning into 03c4d3479284b7719571f403434a32d67a4d5e81 on master.

bsamseth commented 5 years ago

Merging without play strength check because this is the correct way. Even if by chance this reduces strength some, we would rather have a correct engine than fast and incorrect (unstable).