import java.util.Scanner;
public class areaOfCircle
{
    public static void main(String args[])
    {
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter the radius of circle");
        double r=sc.nextDouble();
        //pi=3.1415926535897.... taking pi upto 2 decimal places
        double pi=3.14;
        /*Formula of area of circle =pi*r*r */
        double area=pi*r*r;
        System.out.println("Area of circle="+area);
     }
}