StringBuilder newSB = new StringBuilder("");
            int count = int.Parse(Console.ReadLine());
            String someString = Console.ReadLine();
            for (int i = 0; i < count; i++)
            {
                if (char.IsLetter(someString[i]))
                    newSB.Append(someString[i]);

            }
            Console.WriteLine(newSB);
            Console.ReadKey();