[LeetCode] Maximum Depth of Binary Tree

链接https://leetcode.com/submissions/detail/136407355/

难度:Easy

题目:104. Maximum Depth of Binary Tree

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.

翻译:给定一棵二叉树,找到它的最大深度。最大深度是沿着从根节点到最远叶节点的最长路径的节点的数量。

思路:用深度优先搜索DFS递归遍历二叉树,搜索判断左右子树的深度孰大孰小即可,从根节点往下一层树的深度即自增1,遇到NULL时即返回0。

参考代码

Java

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/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
class Solution {
public int maxDepth(TreeNode root) {
if(root == null)
return 0;
return (1+Math.max(maxDepth(root.left), maxDepth(root.right)));
}
}