mirror of
https://github.com/sockspls/badfish
synced 2025-05-01 01:03:09 +00:00
77 lines
2.3 KiB
C++
77 lines
2.3 KiB
C++
/*
|
|
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
|
|
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
|
|
Copyright (C) 2008 Marco Costalba
|
|
|
|
Stockfish is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
Stockfish is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
|
|
#if !defined(HISTORY_H_INCLUDED)
|
|
#define HISTORY_H_INCLUDED
|
|
|
|
////
|
|
//// Includes
|
|
////
|
|
|
|
#include "depth.h"
|
|
#include "move.h"
|
|
#include "piece.h"
|
|
|
|
|
|
////
|
|
//// Types
|
|
////
|
|
|
|
/// The History class stores statistics about how often different moves have
|
|
/// been successful or unsuccessful during the current search. These
|
|
/// statistics are used for reduction and move ordering decisions.
|
|
|
|
class History {
|
|
|
|
public:
|
|
History();
|
|
void clear();
|
|
void success(Piece p, Move m, Depth d);
|
|
void failure(Piece p, Move m);
|
|
int move_ordering_score(Piece p, Move m) const;
|
|
bool ok_to_prune(Piece p, Move m, Depth d) const;
|
|
|
|
private:
|
|
int history[16][64]; // [piece][square]
|
|
int successCount[16][64];
|
|
int failureCount[16][64];
|
|
};
|
|
|
|
|
|
////
|
|
//// Constants and variables
|
|
////
|
|
|
|
/// HistoryMax controls how often the history counters will be scaled down:
|
|
/// When the history score for a move gets bigger than HistoryMax, all
|
|
/// entries in the table are divided by 2. It is difficult to guess what
|
|
/// the ideal value of this constant is. Scaling down the scores often has
|
|
/// the effect that parts of the search tree which have been searched
|
|
/// recently have a bigger importance for move ordering than the moves which
|
|
/// have been searched a long time ago.
|
|
///
|
|
/// Note that HistoryMax should probably be changed whenever the constant
|
|
/// OnePly in depth.h is changed. This is somewhat annoying. Perhaps it
|
|
/// would be better to scale down the history table at regular intervals?
|
|
|
|
const int HistoryMax = 50000;
|
|
|
|
|
|
#endif // !defined(HISTORY_H_INCLUDED)
|