creating a binary tree and entering the nodes
Node * root = newNode ( 1 ) ; root -> left = newNode ( 2 ) ; root -> right = newNode ( 3 ) ; root -> left -> left = newNode ( 4 ) ; root -> left -> right = newNode ( 5 ) ; cout << " Size ▁ of ▁ the ▁ tree ▁ is ▁ " << sizeoftree ( root ) << endl ; return 0 ; }