public void TestMalfromedDblLinkedList2()
        {
            var d = new MalformedDblLinkedList.Node<char> { Value = 'D' };
            var c = new MalformedDblLinkedList.Node<char> { Value = 'C', Next = d };
            var b = new MalformedDblLinkedList.Node<char> { Value = 'B', Next = c };
            var a = new MalformedDblLinkedList.Node<char> { Value = 'A', Next = b };
            b.BackPtr = d;
            c.BackPtr = b;
            d.BackPtr = a;

            DeepCopyVerify(a);
        }
        public void TestMalfromedDblLinkedList3()
        {
            var e = new MalformedDblLinkedList.Node<char> { Value = 'E' };
            var d = new MalformedDblLinkedList.Node<char> { Value = 'D', Next = e };
            var c = new MalformedDblLinkedList.Node<char> { Value = 'C', Next = d };
            var b = new MalformedDblLinkedList.Node<char> { Value = 'B', Next = c };
            var a = new MalformedDblLinkedList.Node<char> { Value = 'A', Next = b };
            b.BackPtr = a;
            c.BackPtr = e;
            d.BackPtr = c;
            e.Next = null; e.BackPtr = b;

            DeepCopyVerify(a);
        }