Author: Dann Corbit
Date: 10:04:47 07/29/03
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On July 29, 2003 at 11:38:40, Russell Reagan wrote: >On July 29, 2003 at 03:07:18, Dann Corbit wrote: > >>Well, you are right. For a repetition hash table no need to bother storing any >>depth information. It's irrelevant. > >>Sure. But it's rare. If you are going to use a hash table to detect >>repetitions you will have to: >> Live with an occasional blunder due to overwrite > >This may be the source of my confusion -> Did you mean A) use the main >transposition hash table to detect repetitions, or B) use a seperate, smaller >hash table to detect repetitions, as Bruce does in Gerbil? Separate table. I have used the same hash functions to manipulate all different hash tables, though. >I assumed you meant A (not sure why), but I use B. I think that by using a small >hash table, you are safe. Even if there are 600 positions that occured in the >game, if you use a 64-bit key, that is...gosh, really good odds :) You will never have to worry about more than 100 of them, since every capture or pawn push resets the list. Collisions are more frequent than people imagine because of the birthday paradox. You start running into trouble at around sqrt(key_size) stores, typically.
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