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Subject: Re: a comment and a question to anyone

Author: Charles Roberson

Date: 09:52:17 02/10/03

Go up one level in this thread


>>        v = -Search(-alpha,-beta)   // second value
>
>you mean (-beta,-alpha)
     Yes, I meant (-beta,-alpha)


>
>>  Adjusted algorithm:
>>     v = -Search(-alpha-1,-alpha);
>>     if ((v>alpha) && (v<beta))
>>     {
>>       int nalpha, nbeta;
>>       nalpha = v - (pawnvalue>>3);
>>       nbeta  = v + (pawnvalue>>3);
>
>perhaps you mean
>        nalpha = max (alpha, v - (pawnvalue>>3));
>        nbeta  = min (beta , v + (pawnvalue>>3));

       Actually, I typed what I did in this case. But, you are correct the
       proper way to do it is with the use of min and max as you have.
       So, I retried and I have similar results on plys<= 8 and a 79% speedup
       on the 9ply searches.

>
>>       v = -Search(-nbeta,-nalpha);
>>
>>       if ((v<nalpha) || (v>nbeta))
>>          v = -Search(-beta, -alpha);
>>     }
>




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