private static double conversion(double a, double b, double c, double d)
double one = (a + b + c + d);
public static void Main()
Console.WriteLine("please enter four numbers."); double two = double.Parse(Console.ReadLine());
double three = double.Parse(Console.ReadLine());
double four = double.Parse(Console.ReadLine());
double five = double.Parse(Console.ReadLine());
Console.WriteLine("your answer is" + conversion(two, three, four, five));
