Console.WriteLine("введите номер кашей карты");
            string cardNumber = Console.ReadLine();
            int count = cardNumber.Length;
            long card = long.Parse(cardNumber);
            if (13 <= count && count <= 16)
            {

                while (card > 10)
                {
                    card = card / 10;

                }
                Console.WriteLine(card);
                if (card == 4)
                {
                    Console.WriteLine("Your card type is Visa");
                }
                if (card == 5)
                {
                    Console.WriteLine("Your card type is MasterCard");
                }
                if (card == 6)
                {
                    Console.WriteLine("Your card type is Discover cards");
                }
                while (card > 100)
                {
                    long x = card % 100 / 10;
                    card = card / 100;
                    Console.WriteLine(x);
                }

            }


            else
            {

                Console.WriteLine("invalid card number");
            }