int myst(int n, int m) {

         if (n == 1)
            return n;
         else 
            return n + myst(n-1,m);
      }

      main() 
         cout << myst(4,10);


      display() {
          Node *curr = front;
          while (curr != 0) {

             cout << curr->data;
             curr = curr->next;

          }
      }




      void display(Node *curr) {
           
          if (curr == 0) {  // base case
             ;
          } else {
             cout << curr->data;
             display(curr->next);
          }
         
      }

      void display() {
          display(front);
      }
      
----------------------------------
      main() {
          List myList;
          myList.display();
      }