题解 | #对称的二叉树#

# -*- coding:utf-8 -*-
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None
class Solution:
    def isSymmetrical(self, pRoot):
        # write code here
        if not pRoot:
            return True
        return self.check(pRoot.left,pRoot.right)
    
    def check(self,left,right):
        if not left and not right:
            return True
        if not left or not right or left.val!=right.val:
            return False
        return self.check(left.left,right.right) and self.check(left.right,right.left)```