+
+struct Board {
+ signed char board[BOARD_SIZE];
+ bool is_valid() const;
+ signed char hole() const;
+ InvertedBoard invert() const;
+ int distance(const Board& o) const;
+ int distance(const InvertedBoard& invo) const;
+};
+std::istream& operator>>(std::istream& is, Board& board);
+std::ostream& operator<<(std::ostream& os, const Board& board);
+
+extern signed char adjacent[BOARD_SIZE][5];
+
+#endif /* _SLIDING_TILE_LIB_H */