extern Bitboard SquareBB[SQUARE_NB];
extern Bitboard FileBB[FILE_NB];
extern Bitboard RankBB[RANK_NB];
-extern Bitboard AdjacentFilesBB[FILE_NB];
extern Bitboard ForwardRanksBB[COLOR_NB][RANK_NB];
extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
extern Bitboard LineBB[SQUARE_NB][SQUARE_NB];
/// adjacent files of the given one.
inline Bitboard adjacent_files_bb(File f) {
- return AdjacentFilesBB[f];
+ return shift<EAST>(FileBB[f]) | shift<WEST>(FileBB[f]);
}