[easy] Maximum Depth of Binary Tree

难度: 简单 标题:二叉树最大深度

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.

思路

root == null时深度为0;最大深度为左/右的最大深度+1;

代码

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/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public int maxDepth(TreeNode root) {
if(root == null) return 0;
if(root.left == null && root.right == null) return 1;
int DL = maxDepth(root.left);
int DR = maxDepth(root.right);
return (DL>DR?DL:DR)+1;

}
}

链接

https://leetcode.com/problems/maximum-depth-of-binary-tree/