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Subject: Re: Weird things with hash tables.

Author: Larry Griffiths

Date: 02:35:08 02/25/99

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On February 24, 1999 at 22:19:04, William Bryant wrote:

>On February 24, 1999 at 21:44:34, Larry Griffiths wrote:
>>William,
>>
>>Very nice output!  May I inquire as to how you are able to retain
>>the principle continuation when using hash tables?  Mine seems to
>>get messed up when using a hash table.
>>
>>Larry   :-}
>
>I don't very often at the lower plies.  Note that at 18 plies on the first
>example, the principle continuation is only 5 moves long.  The longer PC(or PV
>as case may be) occurs when the search goes beyond the previous hashed search
>and starts to back up the moves.
>
>I am trying a suggestion of Dr. Hyatt's and not hashing the QSearch code, trying
>to keep the QSearch lean.
>
>He also suggest rebuilding the the PV from the hash table entries if they are
>not overwritten.  I may try this soon (on the list, a long list :)  ) but I am
>concerned about that reduction in speed it may require.
>
>If you come up with a good trick or suggestion, let me know.
>
>William
>wbryant@ix.netcom.com


Thanks William,

At least I know that it is a problem now.  I ran that first position
thru my program and it does the first 16 or 18 plys quickly but then
hits the wall at 20 to 22 plys.  If I try to play the position, then it
gets even worse as I am assuming one of those pawns queens.
My program still beats me as I have not figured out how to win the
opposition when playing that first King and Pawns position.

Larry   :-)




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