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Subject: Re: Does swap of Crafty find bad promotions

Author: Mike Byrne

Date: 17:55:32 01/11/04

Go up one level in this thread


On January 11, 2004 at 17:55:11, Uri Blass wrote:

>On January 11, 2004 at 16:52:09, Robert Hyatt wrote:
>
>>On January 11, 2004 at 15:47:04, Uri Blass wrote:
>>
>>>I do not see a word about promotions in swap.c of Crafty but maybe there is
>>>something that I do not understand.
>>>
>>>Uri
>>
>>Swap() will only find capture promotions.  It really doesn't do anything
>>with them, because the value is a pawn, not a queen, and the normal Swap()
>>code handles that just fine.  IE if you treat it as simply dxe8, that is
>>good enough, you are winning a piece.  If your opponent re-captures, he
>>only gets a pawn, not the queen you promoted to...
>
>If the pawn is pinned you may need to capture with something else.
>
>[D]rn6/P7/K7/8/8/6k1/1Q6/8 w - - 0 1
>
>If I understand correctly
>SEE of Crafty is going to consider QxN as a bad capture.
>
>Uri


sd=1
Black(1): rn6/P7/K7/8/8/6k1/1Q6/8 w - - 0 1
White(1): go
end-game phase
              clearing hash tables
              time surplus  29.75  time limit 22.87 (3:33)
              time surplus  29.75  time limit 22.87 (3:33)
              depth   time  score   variation (1)
                1     0.00  11.45   1. Qxb8+ Rxb8 2. axb8=Q+
                1->   0.00  11.45   1. Qxb8+ Rxb8 2. axb8=Q+
              time=0.00  cpu=100%  mat=2  n=39  fh=100%  nps=10K
              ext-> chk=1 cap=0 pp=0 1rep=0 mate=0
              predicted=1  nodes=39  evals=11
              endgame tablebase-> probes=0  hits=0
              SMP->  split=1  stop=0  data=1/64  cpu=0.00  elap=0.00

White(1): Qxb8+
              time used:   0.00
Black(1):






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