Problem:
Circle

Write a program which calculates the area and circumference of a circle for given radius r.

Input

A real number r is given.

Output

Print the area and circumference of the circle in a line. Put a single space between them. The output should not contain an absolute error greater than 10-5.

Constraints

0 < r < 10000

Sample Input 1

2

Sample Output 1

12.566371 12.566371

Sample Input 2

3

Sample Output 2

28.274334 18.849556

Solution in JAVA (judge verdict: Accepted)

import java.util.Scanner;

public class Main{
    public static void main(String[] args){
	Scanner stdin = new Scanner(System.in);
        double r = stdin.nextDouble();
	double x = Math.PI;
	double s = (double)x*r*r;
	double l = (double)2*x*r;
	System.out.printf("%.6f %.6f %n", s, l);
    }
}