题目浅析

  • 想查看原题可以点击题目链接。

  • 简单地说，就是判断一个二叉树是否轴对称。

思路分享

代码解答（强烈建议自行解答后再看）

  • 参考题解
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def isSame(self, p: Optional[TreeNode], q: Optional[TreeNode]) -> bool:
        if p is None or q is None:
            return p is q
        return p.val == q.val and self.isSame(p.left, q.right) and self.isSame(p.right, q.left) 
    def isSymmetric(self, root: Optional[TreeNode]) -> bool:
        if root is None:
            return True
        return self.isSame(root.left, root.right)