Levels are now expanded out as you travel down and the stairs are only placed at the end of the level instead of randomly.

point.hpp

@@ -15,7 +15,7 @@ struct Point {
 
 typedef std::vector<Point> PointList;
 
-struct PointHash {
+template<> struct std::hash<Point> {
   size_t operator()(const Point& p) const {
     return std::hash<int>()(p.x) ^ std::hash<int>()(p.y);
   }