From 918d0ec0faf27870212b11c4820d4ae956ba8da3 Mon Sep 17 00:00:00 2001
From: jianghongcheng <35664721+jianghongcheng@users.noreply.github.com>
Date: Wed, 3 May 2023 20:40:43 -0500
Subject: [PATCH] =?UTF-8?q?Update=200101.=E5=AF=B9=E7=A7=B0=E4=BA=8C?=
 =?UTF-8?q?=E5=8F=89=E6=A0=91.md?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 problems/0101.对称二叉树.md | 40 ++++++++++++++++++--------------
 1 file changed, 23 insertions(+), 17 deletions(-)

diff --git a/problems/0101.对称二叉树.md b/problems/0101.对称二叉树.md
index b75e9ff2..81ca79a2 100644
--- a/problems/0101.对称二叉树.md
+++ b/problems/0101.对称二叉树.md
@@ -442,25 +442,31 @@ class Solution:
 层次遍历
 ```python
 class Solution:
-    def isSymmetric(self, root: Optional[TreeNode]) -> bool:
+    def isSymmetric(self, root: TreeNode) -> bool:
         if not root:
             return True
-
-        que = [root]
-        while que:
-            this_level_length = len(que)
-            for i in range(this_level_length // 2):
-                # 要么其中一个是None但另外一个不是
-                if (not que[i] and que[this_level_length - 1 - i]) or (que[i] and not que[this_level_length - 1 - i]):
-                    return False
-                # 要么两个都不是None
-                if que[i] and que[i].val != que[this_level_length - 1 - i].val:
-                    return False
-            for i in range(this_level_length):
-                if not que[i]: continue
-                que.append(que[i].left)
-                que.append(que[i].right)
-            que = que[this_level_length:]
+        
+        queue = collections.deque([root.left, root.right])
+        
+        while queue:
+            level_size = len(queue)
+            
+            if level_size % 2 != 0:
+                return False
+            
+            level_vals = []
+            for i in range(level_size):
+                node = queue.popleft()
+                if node:
+                    level_vals.append(node.val)
+                    queue.append(node.left)
+                    queue.append(node.right)
+                else:
+                    level_vals.append(None)
+                    
+            if level_vals != level_vals[::-1]:
+                return False
+            
         return True
 ```