/*

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)

    {

        if(pRoot == NULL) return ;

        return max(+TreeDepth(pRoot->left), +TreeDepth(pRoot->right));

    }

};