9
LeetCode: 104. Maximum Depth of Binary Tree
source link: https://mozillazg.com/2020/12/leetcode-104-maximum-depth-of-binary-tree.html
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.
题目¶
原题地址：https://leetcode.com/problems/maximum-depth-of-binary-tree/
Given the root of a binary tree, return its maximum depth.
A binary tree's maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
Example 1:
Input: root = [3,9,20,null,null,15,7] Output: 3
Example 2:
Input: root = [1,null,2] Output: 2
Example 3:
Input: root = [] Output: 0
Example 4:
Input: root = [0] Output: 1
Constraints:
- The number of nodes in the tree is in the range [0, 104].
- -100 <= Node.val <= 100
解法¶
求左右子树各自的最大深度，然后进行比较取最大值再加一，即为 root 节点的最大深度。
这个方法的 Python 代码类似下面这样:
# 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 maxDepth(self, root):
if root is None:
return 0
return 1 + max(self.maxDepth(root.left), self.maxDepth(root.right))
Recommend
About Joyk
Aggregate valuable and interesting links.
Joyk means Joy of geeK