Author: Tony Werten
Date: 01:33:43 07/04/02
Go up one level in this thread
On July 04, 2002 at 04:19:13, Christophe Drieu wrote:
>On July 03, 2002 at 17:39:25, Art Basham wrote:
>
>>Here is a good link to help anyone new here...
>>
>>http://www.seanet.com/~brucemo/topics/nullmove.htm
>>
>>I am still working on it...:-)
>
>Great, but what MakeNullMove() function do ?
Switch side to move, clear en passant, increase current ply ( to make sure that
everything you stack is on the right place ie. all even plycounters of the
killertable contain white to move ) etc.
Basicly everything you do when you do make a move but now without a move. It
helps if you actually have a nullmove. In my program I use from_sq:=o, to_sq:=0,
from_piece:=0, to_piece:=0 defined as klote_zet ( shitty move ) wich I also use
to initiallize best_move at the start if each search.
Tony
>
>#define R 2
>
>int AlphaBeta(int depth, int alpha, int beta)
>{
> if (depth == 0)
> return Evaluate();
> MakeNullMove();
> val = -AlphaBeta(depth - 1 - R, -beta, -beta + 1);
> UnmakeNullMove();
> if (val >= beta)
> return beta;
> GenerateLegalMoves();
> while (MovesLeft()) {
> MakeNextMove();
> val = -AlphaBeta(depth - 1, -beta, -alpha);
> UnmakeMove();
> if (val >= beta) // Delete these to get straight
> return beta; // min-max instead of alpha-beta.
> if (val > alpha)
> alpha = val;
> }
> return alpha;
>}
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.