(牛客网)二叉树的深度

输入一棵二叉树，求该树的深度。从根结点到叶结点依次经过的结点（含根、叶结点）形成树的一条路径，最长路径的长度为树的深度。

/*struct TreeNode {    int val;    struct TreeNode *left;    struct TreeNode *right;    TreeNode(int x) :            val(x), left(NULL), right(NULL) {    }};*/class Solution {public:    int TreeDepth(TreeNode* pRoot)    {        int left,right;        left=right=1;        if(pRoot==NULL )            return 0;        left += TreeDepth(pRoot->left);        right += TreeDepth(pRoot->right);        return left>right? left :right;    }};