using System;

public class Program

{

    public static void Main()

    {

        double x = 20, y = 3.5, z = 4;

        double ans;

        ans = x + y;

        Console.WriteLine(ans);

        ans = x - y;

        Console.WriteLine(ans);

        ans = x * y;

        Console.WriteLine(ans);

        ans = x / y;

        Console.WriteLine(ans);

        ans = y / z;

        Console.WriteLine(ans);

        ans = x / z;

        Console.WriteLine(ans);

        ans = x / 6;

        Console.WriteLine(ans);

        double a = 20, b = 6;

        ans = a + b;

        Console.WriteLine(ans);

        ans = a - b;

        Console.WriteLine(ans);

        ans = a * b;

        Console.WriteLine(ans);

        ans = a / b;

        Console.WriteLine(ans);

        ans = b / a;

        Console.WriteLine(ans);

        double c = x + y;

    }

}