public void TestMethod18()
        {
            SNode n4 = new SNode {
                data = 5
            };
            SNode n3 = new SNode {
                data = 4
            };
            SNode n2 = new SNode {
                data = 3
            };
            SNode n1 = new SNode {
                data = 2
            };
            SNode head = new SNode {
                data = 1
            };

            head.next = n1;
            n1.next   = n2;
            n2.next   = n3;
            n3.next   = n4;

            Assert.AreEqual(-1, SinglyLinkedListOps.FindCycle(head));
        }
        public void TestMethod19()
        {
            SNode n1 = new SNode {
                data = 2
            };
            SNode head = new SNode {
                data = 1
            };

            head.next = n1;
            n1.next   = head;

            Assert.AreEqual(2, SinglyLinkedListOps.FindCycle(head));
        }