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.

求树的最大深度，也就是求左子树或右子树的最大深度，通过递归，得到最大深度。

public class Solution {    public int maxDepth(TreeNode root) {        if(root==null)           return 0;        if(root.left==null&&root.right==null)           return 1;        else        {            return (1+Math.max(maxDepth(root.left),maxDepth(root.right)));        }    }}