Mark const methods const.

[slidingtile] / sliding_tile_lib.h

diff --git a/sliding_tile_lib.h b/sliding_tile_lib.h
index 7e6004b4aad5b0a6b77140d5c957e986a1afb04b..4d6c0151e45d622c05e3a0ed98a528bbf80405c5 100644 (file)
--- a/sliding_tile_lib.h
+++ b/sliding_tile_lib.h
@@ -1,8 +1,18 @@
 #ifndef _SLIDING_TILE_LIB_H
 #define _SLIDING_TILE_LIB_H
 
+#include <istream>
+
 const int BOARD_DIM = 4;
 const int BOARD_SIZE = BOARD_DIM * BOARD_DIM;
+
+struct Board {
+  signed char board[BOARD_SIZE];
+  bool is_valid() const;
+  signed char hole() const;
+};
+std::istream& operator>>(std::istream& is, Board& board);
+
 extern signed char adjacent[BOARD_SIZE][5];
 
 #endif /* _SLIDING_TILE_LIB_H */