Telerik Exam. Secret Code 2-4-8

namespace _1._2_4_8
{
    using System;

    public class SecretCode
    {
        public static void Main(string[] args)
        {
            checked
            {
                ulong numA = ulong.Parse(Console.ReadLine());
                byte numB = byte.Parse(Console.ReadLine());
                ulong numC = ulong.Parse(Console.ReadLine());

                ulong result = 0;
                if (numB == 2)
                {
                    result = numA % numC;
                }
                else if (numB == 4)
                {
                    result = numA + numC;
                }
                else
                {
                    result = numA * numC;
                }

                if ((result % 4) == 0)
                {
                    Console.WriteLine(result / 4);
                }
                else
                {
                    Console.WriteLine(result % 4);
                }

                Console.WriteLine(result);
            }
        }
    }
}