X-Git-Url: http://git.scottworley.com/slidingtile/blobdiff_plain/f3f55aff4e3346b297215050c2076c821fd60c83..f548f940f95af83b788abf75625d5a5e7fe5617c:/sliding_tile_lib.h

diff --git a/sliding_tile_lib.h b/sliding_tile_lib.h
index 84d422e..c926761 100644
--- a/sliding_tile_lib.h
+++ b/sliding_tile_lib.h
@@ -2,17 +2,35 @@
 #define _SLIDING_TILE_LIB_H
 
 #include <istream>
+#include <memory>
+#include <ostream>
+#include <vector>
 
 const int BOARD_DIM = 4;
 const int BOARD_SIZE = BOARD_DIM * BOARD_DIM;
 
+struct InvertedBoard {
+  signed char pos[BOARD_SIZE];
+};
+
 struct Board {
   signed char board[BOARD_SIZE];
-  bool is_valid();
-  signed char hole();
+  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);
+
+struct Step {
+  Board board;
+  std::shared_ptr<Step> prev;
+  std::vector<Step*> successors(std::shared_ptr<Step> shared_this);
+  static signed char adjacent[BOARD_SIZE][5];
+};
+std::ostream& operator<<(std::ostream& os, const Step& step);
 
-extern signed char adjacent[BOARD_SIZE][5];
 
 #endif /* _SLIDING_TILE_LIB_H */