题目来源:https://leetcode.com/problems/maximum-depth-of-binary-tree/
LeetCode官方题解及解析:104. Maximum Depth of Binary Tree
题目难度:Easy
题目
Given a binary tree, find its maximum depth.
The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
Note: A leaf is a node with no children.
Example:
Given binary tree [3,9,20,null,null,15,7]
,
1 | 3 |
return its depth = 3.