public static void Main(string[] s) { bool tr = true; LinkedList ll=new LinkedList(); while (tr) { System.Console.WriteLine("\nEnter a choice\n1.Add\n2.Delete\n3.Print Linked List\n4.Print Length of List\n5.Exit"); int a = int.Parse(System.Console.ReadLine()); switch (a) { case 1: bool tr1 = true; while (tr1) { System.Console.WriteLine("\nPlease enter a choice:\n1.Add at Beginning\n2.Add in middle\n3.Add at end\n4.Print Linked List\n5.Print Length of List\n6.Back"); int sw = int.Parse(System.Console.ReadLine()); switch (sw) { case 1: System.Console.WriteLine("Enter element to enter:"); int ad = int.Parse(System.Console.ReadLine()); ll.addFirst(ad); break; case 2: System.Console.WriteLine("Enter element to enter:"); ad = int.Parse(System.Console.ReadLine()); System.Console.WriteLine("Enter the index :"); int n = int.Parse(System.Console.ReadLine()); ll.addIndex(ad, n); System.Console.WriteLine(); break; case 3: System.Console.WriteLine("\nEnter element to enter:"); ad = int.Parse(System.Console.ReadLine()); ll.addLast(ad); break; case 4: ll.printList(first); break; case 5: System.Console.WriteLine(ll.printLength()); break; case 6: tr1 = false; break; default: System.Console.WriteLine("Invalid Choice!!!"); break; } } break; case 2: bool tr2 = true; while (tr2) { System.Console.WriteLine("\nPlease enter a choice:\n1.Delete at Beginning\n2.Delete in middle\n3.Delete at end\n4.Print Linked List\n5.Print Length of List\n6.Back"); int sw = int.Parse(System.Console.ReadLine()); switch (sw) { case 1: ll.deleteFirst(); break; case 2: System.Console.WriteLine("Enter pos to del the element:"); int ps = int.Parse(System.Console.ReadLine()); ll.deleteIndex(ps); break; case 3: ll.deleteLast(); break; case 4: ll.printList(first); break; case 5: System.Console.WriteLine(ll.printLength()); break; case 6: tr2 = false; break; default: System.Console.WriteLine("Invalid Option!!"); break; } } break; case 3: ll.printList(first); break; case 4: System.Console.WriteLine(ll.printLength()); break; case 5: tr = false; break; default: System.Console.WriteLine("Invalid Option!!"); break; } } }