leetcode 101.对称二叉树（不会做）

遇到递归就抓瞎# Definition for a binary tree node. # class TreeNode: # def __init__(self, val0, leftNone, rightNone): # self.val val # self.left left # self.right right class Solution: def isSymmetric(self, root: Optional[TreeNode]) - bool: if not root: return root return self.check(root.left,root.right) def check(self,left_node: Optional[TreeNode],right_node: Optional[TreeNode]): if left_node None and right_node None: return True if left_nodeNone or right_nodeNone: return False if left_node.val ! right_node.val: return False outside self.check(left_node.left,right_node.right) inside self.check(left_node.right,right_node.left) return outside and inside