C# test

Question

Hello everyone. I am trying to learn C# and I got the right answer but I don't know how to implement it in a way to get all cases correct.

I am trying to pass this code project.
https://www.sololearn.com/learning/eom-project/1080/1016

Here is my code which gives me the first case correct but if I uncomment the other code, then I get all of them wrong but the answers are correct.

Can someone help me understand why is not working? Thanks.

static void Main(string[] args)
{
const double pi = 3.14;
double radius;

//your code goes here
static double areaOfCircle(double radius)
{
return pi * radius * radius;
}
Console.WriteLine(areaOfCircle(5));
//Console.WriteLine(areaOfCircle(6.4));
//Console.WriteLine(areaOfCircle(10));
}

Answer 1

//your code goes here .. Area of the circle

radius = Convert.ToDouble(Console.ReadLine());
double area = pi * Math.Pow(radius,2); //or double area = pi * (radius*radius);
Console.WriteLine(area);

Answer 2

You need to get user input rather than hard code all the test

Answer 3

// Thank you very much for the help. Raul Ramirez and SoloProg.
// It really helped me understand. Appreciate it!
// Wish you guys the best!
// Here it is my final code after understanding in case anyone else stumble across this question.

static void Main(string[] args)
{
const double pi = 3.14;
double radius;

static double areaOfCircle(double radius)
{
return pi * radius * radius;
}
radius = Convert.ToDouble(Console.ReadLine());
Console.WriteLine(areaOfCircle(radius));
}