#include <iostream>
using namespace std;

class node {
public:
    int data;
    node* left;
    node* right;

    node(int d) {
        this->data = d;
        this->left = NULL;
        this->right = NULL;
    }
};

node* buildTree() {
    cout << "Enter the data (-1 for no node): "<<endl;
    int data;
    cin >> data;

    if (data == -1) {
        return NULL;
    }

    node* root = new node(data); // Create a new node

    cout << "Enter data for left child of " << data << ": "<<endl;
    root->left = buildTree();
    cout << "Enter data for right child of " << data << ": "<<endl;
    root->right = buildTree();
    
    return root;
}
 
int main() {
    node* root = buildTree(); // Create the tree starting from root
    return 0;
}