Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Another interesting Anti-Null move position (from a real game)

Author: Anthony Cozzie

Date: 18:45:44 06/14/04

Go up one level in this thread


On June 14, 2004 at 20:12:09, Omid David Tabibi wrote:

>On June 14, 2004 at 19:20:57, Anthony Cozzie wrote:
>
>>On June 14, 2004 at 16:31:17, Jaime Benito de Valle Ruiz wrote:
>>
>>>[d]8/8/1p4p1/p5kp/Pp1QP1Pq/1P6/6K1/8 w - - 0 62
>>>
>>>White moves and wins!
>>>Can your engine find the right answer and give the proper "crushing" score
>>>(around 9 pawns!) along with a proper PV? How long does it take?
>>>Mine doesn't find anything after a long long time (over an hour), but with
>>>null-move disabled, it takes only a few seconds to show the full PV.
>>>(Some engines find the right answer, but with a small score, an absurd PV, and
>>>they change their mind some plies later)
>>>
>>>In this position the black king is in a very delicate position: After a couple
>>>of moves, if the black queen moves, white checkmates inmediately, so both kings
>>>and queens must remain still while pawns play on their own.
>>>
>>>Any good suggestion to avoid this problem with null-move?
>>>
>>>Regards,
>>>
>>>  Jaime
>>
>>Zappa doesn't get it either (gxh5 @ 15 ply after 1 minute).  Zappa relies on
>>double nullmove for zugzwang avoidance.  This works find for positions with 1
>>zugzwang, but in this position black gets hit with about 10 of them :)
>
>Ehem, ehem, heard about verified null-move pruning? :)
>
>
>>
>>anthony


It's a possibility.  If I understand it correctly verifications performed
nonrecursively.

Right now, my goals are "Deep Zappa" aka "ParZappa" aka "Zappa-NUMA" aka "Zappa"
and the autotuning stuff; when I get some free time I'll try to give it a shot.

Oh, and I have to rewrite my eval again.

anthony



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.