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Article #4977Small change to search.
From: Chua Kong Sian
Date: Tue, 23 Aug 1994 01:01
Date: Tue, 23 Aug 1994 01:01
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1117 bytes
Here is a small change to prune away unnecessary leaf nodes in gnuchess. In search.c, at lines 1010 or thereabouts, change for (pnt = pbst = TrPnt[ply]; pnt < TrPnt[ply + 1] && best <= beta; pnt++) to for (pnt = pbst = TrPnt[ply]; pnt < TrPnt[ply + 1] && best <= beta && best != 9999-ply; pnt++) I've seen up to 25% reduction in nodes search for some positions with plenty of mates. If there are no mates, there will be little improvement. Kong Sian
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X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 10d71d,3a04db19f883ca9d,start X-Google-Attributes: gid10d71d,public X-Google-ArrivalTime: 1994-08-22 19:11:05 PST Path: arc1-ca.pugleaf.net!bga.com!news.sprintlink.net!uunet!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!newsserver.jvnc.net!raffles.technet.sg!nuscc.nus.sg!nsrccks From: nsrccks@leonis.nus.sg (Chua Kong Sian) Newsgroups: gnu.chess Subject: Small change to search. Date: 23 Aug 1994 01:01:44 GMT Organization: National University of Singapore Lines: 15 Message-ID: <33bhpo$5vr@nuscc.nus.sg> NNTP-Posting-Host: leonis.nus.sg X-Newsreader: TIN [version 1.2 PL2]