Author: Rick Bischoff
Date: 14:00:48 07/30/03
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Hi, What is happening exactly: a. at depth 3- hash table is empty for this position. alpha = -INF, beta = +INF a. all requirements for null move are met a. makes null move: int e = -alphabeta(depth - 3, -beta, -beta +1); b. now we are at depth 0, alpha = -INF, beta = -INF + 1 b. we call quies(alpha, beta) c. e = static eval is, oh say, 1. c. e >= beta, return beta b. store this position in the hash table as -INF + 1, exact, depth = 0, return -INF + 1 (at which point the program threw an exeption because I didn't want out of bounds scores stored as exact..) a. e = -(-INF + 1) = INF - 1 a. e is not greater than beta, so do normal search. >Are you backing up values correctly? At the next search you will fail >high, which will back up a fail-low value to the current ply, meaning >the null-move search fails low and you just wasted some nodes.
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