Author: Geoff
Date: 14:10:32 04/26/03
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Hello Tom
Thanks for putting me out of my misery, I still hadn't spotted the problem ;-)
You are correct that was what was causing the problem, I commented out the lines
if (ply && reps())
return 0;
just to prove the point and it then finds the correct solution
10: 9991 4034 30732760 g5c5 h5g5 c5f5 g5h5 f5g5 h5g5 a5g5 a6a5 g5a5
it makes sense that this test position showed up the problem as black has a move
sequence g5h5 h5g5 and white has a sequence a5g5 g5a5 even though there isn't an
actual board repeat.
Looks like that clever algorithm for reps detection was to too smart for its own
good. Pity as it looked speedy, guess I will have to put the hash code in now
instead, or maybe spot the flaw in the original algorithm
Thanks for the help.
Geoff
On April 26, 2003 at 15:02:47, Tom Kerrigan wrote:
>I wrote you an e-mail about this, but might as well post as well.
>
>The change between 1.7 and 1.8 in the search code is the repetition detection
>method. I know the 1.7 rep detector was buggy, so it must have thought there was
>some sort of repetition in the mating line.
>
>-Tom
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