leetCode 104.Maximum Depth of Binary Tree（二叉树最大深度） 解题思路和方法

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：非常基础的一个题。DFS就可以。代码例如以下：

/**
* 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) {
//没有根节点
if(root == null){
return 0;
}
int dep1 = maxDepth(root.left);
int dep2 = maxDepth(root.right);
return dep1 > dep2 ? dep1+1:dep2+1;
}
}