(java)leetcode 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.

思路:本题就是最简单的树的遍历题，DFS和BFS都可以，我是采用的BFS

代码如下 (已通过leetcode)

/**
 * 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) {
int maxdepth=0;
if(root==null) return 0;
int l=maxDepth(root.left);
int r=maxDepth(root.right);
return l>r?l+1:r+1;
}
}