1002 Area of a Circle URI Problem Only Solution In C#

using System;

class URI {
   

    static void Main(string[] args) {
       
         double PI=3.14159;

        double r =Convert.ToDouble(Console.ReadLine());
       
        double area=PI*r*r;
       
        Console.WriteLine("A="+area.ToString("0.0000"));
       
    }

}