最深二叉树 （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： 给定一个二叉树，找到其深度。

此题比较简单，实现如下:

/**
* Definition for binary tree
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public int maxDepth(TreeNode root) {
if(null == root) return 0;

return Math.max(maxDepth(root.left), maxDepth(root.right)) + 1;
}
}