public void Add(Node node)
 {
     if (head == null)
     {
         head = node;
         current = node;
     }
     else
     {
         current.Next = node;
         current = node;
     }
 }
        private LinkedList _ConstructLinkedListWithLoop()
        {
            Node n1 = new Node(10);
            Node n2 = new Node(20);
            Node n3 = new Node(30);
            Node n4 = new Node(40);
            Node n5 = new Node(50);
            Node n6 = new Node(60);

            n1.Next = n2;
            n2.Next = n3;
            n3.Next = n4;
            n4.Next = n5;
            n5.Next = n6;
            n6.Next = n3;

            LinkedList lnkdLst = new LinkedList();
            lnkdLst.head = n1;

            return lnkdLst;
        }