Author: Peter Alloysius
Date: 06:04:16 07/28/04
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>>>I visited Aske Plaat's site and slapped MTD(f) into my >>>program, keeping the existing PVS/NEGASCOUNT in lieu of implementing >>>his AlphaBetaWithMemory(). This is perfectly okay according to Aske. >>> >> >>you should implement his AlphaBetaWithMemory(), or your program will take >>9999999 iterations to find mate value. If value found by alphabeta is above beta >>or below alpha, return that real value, not the alpha/beta. > >Exactly. And things do look somewhat better with the return alpha/beta >vs. return value under conditional compilation. > >As the other author has pointed out, instabilities still abound with >the current implementation and it is no where near PVSNEGASCOUT in >performance nor reliability in its early form, obviously. > >But good call and a good laugh. I think that Plaat's AlphaBetaWithMemory() is somewhat what we called fail-soft ab, right? (if i don't mistaken it, i'm still confused with those terms) with that, my mtd(f) engine *always* need only two iterations to find mate value, one to get upperbound and another to get lowerbound. So, if you need hundred iteration to find mate value, then your search() surely return alpha/beta instead of true value (in this case is mate value). Return that true value and no need to worry about accelerator or instability in your case. CMIIW
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