LeetCode 풀기 - 1026. Maximum Difference Between Node and Ancestor

1026. Maximum Difference Between Node and Ancestor

https://leetcode.com/problems/maximum-difference-between-node-and-ancestor/

Maximum Difference Between Node and Ancestor - LeetCode

문제)

솔루션1) Recursive

Consistency is a key!!!

2021년 마지막 문제 풀이입니다.

# 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 maxAncestorDiff(self, root: Optional[TreeNode]) -> int:        
        def recur(node, min_val, max_val):
            if node is None:
                return 0
            
            max_diff = max(abs(min_val - node.val), abs(max_val - node.val))            
            min_val = min(min_val, node.val)
            max_val = max(max_val, node.val)
            return max(recur(node.left, min_val, max_val), recur(node.right, min_val, max_val), max_diff)
        
        return recur(root, root.val, root.val)