Update 0102.二叉树的层序遍历.md

problems/0102.二叉树的层序遍历.md

@@ -178,12 +178,11 @@ python3代码：
 #         self.val = val
 #         self.left = left
 #         self.right = right
-from collections import deque
 class Solution:
     def levelOrder(self, root: Optional[TreeNode]) -> List[List[int]]:
         if not root:
             return []
-        queue = deque([root])
+        queue = collections.deque([root])
         result = []
         while queue:
             level = []