题目

题解

# 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 rob(self, root: Optional[TreeNode]) -> int:memo = dict()if not root:return 0if root in memo:return memo[root]do_rob = root.valif root.left:do_rob += self.rob(root.left.left)do_rob += self.rob(root.left.right)if root.right:do_rob += self.rob(root.right.left)do_rob += self.rob(root.right.right)not_do_rob = self.rob(root.left) + self.rob(root.right)res = max(do_rob, not_do_rob)memo[root] = resreturn res