diff --git a/wozek.py b/wozek.py
index 98a6dfe..8507242 100644
--- a/wozek.py
+++ b/wozek.py
@@ -280,7 +280,8 @@ def bfs(isstate,final):
         explored.append(node)
         successors=succ(node)
         for successor in successors:
-            fringe.append(successor)
+            if (successor not in fringe and successor not in explored):
+                fringe.append(successor)
 
 # Main game loop
 def game_loop():