using System;

 public class CalcMath

{

     public static void Main()

    {

    int r;  

     Console.WriteLine(" ENTER The radius");

     r=int.Parse(Console.ReadLine());

     Console.WriteLine("Area={0}",r*r*3.14);

     Console.WriteLine("Area={0:f}",r*r*3.14);       

     Console.WriteLine("Area={0:n}",r*r*3.14);  

     Console.WriteLine();

    }

}