diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -19,7 +19,7 @@
         now = x
         while connects[now][0] != -1:
             now = connects[now][0]
-            front.append(now)
+            front.append(now + 1)
         now = x
         while connects[now][1] != -1:
             now = connects[now][1]
