Update convert_binary_search_tree_to_doubly_linked_list.py

yingl · web-flow · commit 79d4efb57cc3 · 2017-04-25T18:38:31.000+08:00
diff --git a/convert_binary_search_tree_to_doubly_linked_list.py b/convert_binary_search_tree_to_doubly_linked_list.py
@@ -1,4 +1,4 @@
-# -*- coding: utf-8 -*-
+# coding: utf-8
 
 class Solution:
     def __init__(self):
@@ -21,4 +21,6 @@ def bstToDoublyList(self, root):
                 node.prev = self.tail
             self.tail = node
             self.bstToDoublyList(root.right)
-        return self.head
+        return self.head
+
+# medium: http://lintcode.com/zh-cn/problem/convert-binary-search-tree-to-doubly-linked-list/
