Author: Tony Werten
Date: 11:23:34 07/31/03
Go up one level in this thread
On July 30, 2003 at 17:18:12, Rick Bischoff wrote: >>> >>>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 >> >>This is _way_ wrong. How can it be "exact"??? It is impossible for the >>search to return valid scores outside alpha/beta window as defined at the >>root. If you are returning an "edge" then it must be an upper or lower >>edge, not an exact score. > >Yes, I know it is wrong-- which is why I was asking the question to begin with >:-) What I do know is store anything quies returns as exact-- but you are >telling me I can't do that, right? (Forgive my ignorance!) You are correct (despite what the others say), but only if you use the failsoft version of alphabeta. Tony
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