public class hw5
{
   static ListElem insert(ListElem L, int v)
   {
      ListElem p;

      if ( L == null )
      {
         p = new ListElem(v);
         p.next = null;
         return(p);
      }
      else if ( v < L.value )
      {
         p = new ListElem(v);
         p.next = L;
         return(p);
      }
      else
      {
         p = insert(L.next, v);
         L.next = p;
         return(L);
      }
   }

   static ListElem delete(ListElem L, int v)
   {
      ListElem p;

      if ( L == null )
      {
         return(null);
      }
      else if ( L.value == v )
      {
         return(L.next);
      }
      else
      {
         p = delete(L.next, v);
         L.next = p;
         return(L);
      }
   }


   static void PrintList(ListElem L)
   {
      System.out.print("The list is ---> ");
      while (L != null)
      {
         System.out.print(L.value + " ");
         L = L.next;
      }
   }



   public static void main(String[] args)
   {
      ListElem L = null;

      L = insert(L, 1500);
      System.out.println("Test case: insert in empty list: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1500");
   
      L = insert(L, 2500);
      System.out.println("Test case: insert at tail: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1500 2500");

      L = insert(L, 1000);
      System.out.println("Test case: insert at head: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1000 1500 2500");
   
      L = insert(L, 2000);
      System.out.println("Test case: insert at middle: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1000 1500 2000 2500");


      L = delete(L, 5500);
      System.out.println("Test case: delete non-existing element: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1000 1500 2000 2500");

      L = delete(L, 1500);
      System.out.println("Test case: delete at middle: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1000 2000 2500");

      L = delete(L, 2500);
      System.out.println("Test case: delete at tail: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 1000 2000");

      L = delete(L, 1000);
      System.out.println("Test case: delete at head: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = 2000");

      L = delete(L, 2000);
      System.out.println("Test case: delete last element: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = (empty)");

      L = delete(L, 2000);
      System.out.println("Test case: delete from empty list: ");
      PrintList(L);
      System.out.println();
      System.out.println("Correct output = (empty)");
   }
}