X-Git-Url: http://git.scottworley.com/slidingtile/blobdiff_plain/9c32325fbc48baf135d0d7840e99ded70cb738f5..49358f3664c36c346dba758ae1b7da9106c42e3b:/sliding_tile_lib.h

diff --git a/sliding_tile_lib.h b/sliding_tile_lib.h
index c5d0a8b..c926761 100644
--- a/sliding_tile_lib.h
+++ b/sliding_tile_lib.h
@@ -2,7 +2,9 @@
 #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;
@@ -22,6 +24,13 @@ struct Board {
 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 */