public void OJ019_RemoveNthNodeFromEndOfListTest3()
 {
     ListNode l1 = new ListNode(1);
     l1.next = new ListNode(2);
     ListNode result = new OJ019_RemoveNthNodeFromEndOfList().RemoveNthFromEnd(l1, 2);
     Assert.AreEqual(2, result.val);
 }
 public void OJ019_RemoveNthNodeFromEndOfListTest2()
 {
     ListNode l1 = new ListNode(1);
     ListNode result = new OJ019_RemoveNthNodeFromEndOfList().RemoveNthFromEnd(l1, 1);
     Assert.AreEqual(null, result);
 }