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Subject: Re: double nullmove??

Author: Inmann Werner

Date: 14:35:50 08/06/00

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Hello.

Where is the benefit in this doing nullmoves only, if the last 2 moves where no
nullmoves? (I do it, if the last move was no nullmove.)

Greetings

Werner


<snip>

>    /* double nullmove */
>   if( !incheck
>    && (realply <= 1  // first 2 ply you always can nullmove,
>        || movelist[realply-1]
>        || movelist[realply-2] ) {
>     /* so we do NOT nullmove if the previous 2 moves were nullmoves
>        or if we are in check
>      */
>     R = 2; /* in DIEP i'm using R=3, but i do checks in qsearch */
>     movelist[realply] = 0; /* 0 means we do nullmove this real move */
>     score = -pvs(depth-1-R,realply+1,side^1,-beta,-beta+1);
>     /* we nullmove with a nullwindow of  [beta-1,beta], as we are
>        only interested in getting a cutoff
>      */
>     if( score >= beta ) {
>       StoreHash(..);
>       return(score);
>     }
>   }

<snip>



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