//
//	p.108
//
//	Reading assignment Chapter 2
//

import java.util.Scanner;

public class CircleCalculation2
{
		public static void main(String[] args)
		{
			double radius, area;
			// final double PI = 3.14159;

			Scanner keyboard = new Scanner(System.in);

			System.out.println("Enter the radius: ");
			radius = keyboard.nextDouble();

			area = Math.PI * radius * radius;		// p.401

			System.out.println("A circle with the radius of " + radius);
			System.out.println("has a area of " + area);
		}
}