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Subject: Re: Why hash tables? Where do programs spend the majority of the CPU ti

Author: John Coffey

Date: 15:31:14 09/16/98

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On September 16, 1998 at 18:23:09, Robert Hyatt wrote:
>You apparently misunderstand the concept.  "hash tables" (more correctly
>called transposition/refutation tables) store the results of searches at
>nodes inside the tree.  so that if I search the move path Nf3 Nf6 Ng5 and
>search some more stuff deeper into the tree, when I get back to the position
>after these three moves I store the search result in the hash table.  Then
>when search the moves Nh3 Nf6 Ng5 I reach the same position by different
>moves, but I find the result of the other search from this position and
>don't have to repeat it...

Thanks for the response.

Is there a limit to the depth that you will store positions into the
hash table?  Does the hash table add much overhead?

Back to my other question:  Do programs spend more time evaluating the positions
than they do traversing the tree?

John Coffey



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