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.

代码如下：

/** * Definition for a binary tree node. * struct TreeNode { *     int val; *     TreeNode *left; *     TreeNode *right; *     TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */class Solution {public:    int maxDepth(TreeNode* root) {        if(root == NULL)            return 0;       int depth = 1;       Depth(root,depth,1);       return depth;    }        void Depth(TreeNode* root,int& depth,int count)    {        if(root == NULL)            return;                    if(count > depth)            depth = count;                Depth(root->left,depth,count+1);        Depth(root->right,depth,count+1);    }};