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 in = new Scanner(System.in);
		double r = Double.parseDouble(in.next());
		final double pi = Math.PI;
		double area = Math.pow(r, 2) * pi;
		double length = 2 * r * pi;
		
		System.out.println(String.format("%.6f", area) + " " + String.format("%.6f", length));
	}
}