public static void D() { Console.WriteLine("(D) Using BigToLong method."); BigNum bigNumC1 = new BigNum(35L); long? num1 = bigNumC1.BigToLong(); Console.WriteLine(num1); BigNum bigNumC2 = new BigNum(9223372036854775807L); long? num2 = bigNumC2.BigToLong(); Console.WriteLine(num2); BigNum bigNumD = new BigNum(); bigNumD.Complement(); long?num3 = bigNumD.BigToLong(); Console.WriteLine(num3); Console.WriteLine(); }