/* 
* Copyright (c) 2011 alexingcool. All Rights Reserved. 
*/ 
#include <iostream>

using namespace std;

struct Node {
 Node(int i = 0, Node *l = NULL, Node *r = NULL) : data(i), left(l), right(r) {}

 int data;
 Node *left;
 Node *right;
};

Node* Construct() {
 Node *node4 = new Node(7, NULL, new Node(3));
 Node *node3 = new Node(4);
 Node *node2 = new Node(12);
 Node *node1 = new Node(5, node3, node4);
 Node *root = new Node(10, node1, node2);
 return root;
}

int GetTreeHeight(Node *root) {
 if(root == NULL)
 return 0;
 return max(GetTreeHeight(root->left) + 1, GetTreeHeight(root->right) + 1);
}

void main() {
 Node *root = Construct();
 int height = GetTreeHeight(root);
 cout << "tree height is: " << height << endl;
}