Fix reward of sparse setting

mujoco_maze/maze_env.py

@@ -565,15 +565,15 @@ def _reward_fn(maze_id: str, dense: str) -> callable:
     else:
         if maze_id in ["Maze", "Push", "BlockMaze"]:
             return (
-                lambda obs, goal: -0.001
+                lambda obs, goal: 1.0
                 if np.linalg.norm(obs[:2] - goal) <= 0.6
-                else 1.0
+                else -0.0001
             )
         elif maze_id == "Fall":
             return (
-                lambda obs, goal: -0.001
+                lambda obs, goal: 1.0
                 if np.linalg.norm(obs[:3] - goal) <= 0.6
-                else 1.0
+                else -0.0001
             )
         else:
             raise NotImplementedError(f"Unknown maze id: {maze_id}")