using System;

public class Program

{

    static double GetDiscriminant(double a, double b, double c) {

        // don't ask why we need static - you will know later

        return b * b - 4 * a * c;

    }

    public static void Main()

    {

        double a = 2, b = 4, c = 2;

        double d = GetDiscriminant(a,b,c);

        Console.WriteLine("d: {0}",d);

        if (d > 0) {

            double root1 = (-b + Math.Sqrt(d))/(2*a);

            double root2 = (-b - Math.Sqrt(d))/(2*a);

            Console.WriteLine("Roots: {0},{1}",root1,root2);

        } else if (d == 0) {

            double root = -b/(2*a);

            Console.WriteLine("Double root: {0}",root);

        } else {

            Console.WriteLine("No real roots");

        }

    }

}