public ListNode removeFirst(ListNode head) 
{ 
  if (head == null) 
    throw new NoSuchElementException();
   ListNode temp = head.getNext();
   head.setNext(null); return temp;
}
public int size(ListNode head)
{
  for(int i = 0; i <= head.nodeCount; i++);
  return i;
}
public int size(ListNode head, Integer i)
{
  if(i < head.nodeCount)
    size(head, ++i);
  return i;
}
public ListNode add(ListNode head, Object value)
{
  ListNode newNode = new ListNode(value, null);
  if (head == null)
    head = newNode;
  else 
  { 
     ListNode node = head; 
     while (node.getNext() != null)
       node = node.getNext();
     node.setNext(newNode);
   }
   return head; 
}
public ListNode concatenateSTRINGS(lISTnODE HEAD)