Driver program
int main ( ) { Node * root = new Node ( 1 ) ; root -> left = new Node ( 2 ) ; root -> right = new Node ( 3 ) ; root -> left -> left = new Node ( 4 ) ; root -> right -> left = new Node ( 5 ) ; root -> right -> right = new Node ( 6 ) ; root -> right -> left -> right = new Node ( 7 ) ; root -> right -> right -> right = new Node ( 8 ) ; root -> right -> left -> right -> left = new Node ( 9 ) ;