X-Git-Url: http://git.scottworley.com/slidingtile/blobdiff_plain/cada47bfe401f2084c4248df10cdf0488bc8750a..49358f3664c36c346dba758ae1b7da9106c42e3b:/sliding_tile_lib.h

diff --git a/sliding_tile_lib.h b/sliding_tile_lib.h
index d144789..c926761 100644
--- a/sliding_tile_lib.h
+++ b/sliding_tile_lib.h
@@ -2,19 +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() 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];
+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);
+
 
 #endif /* _SLIDING_TILE_LIB_H */