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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws IOException {
		double r = 0;
		double pi = Math.PI;
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String str = br.readLine();
		
		r = Double.parseDouble(str);
		
		double equ = r * r * pi; 
		double loc = r * 2 * pi;
		
		String eAnswer = String.format("%.6f", equ);
		String lAnswer = String.format("%.6f", loc);
		
		System.out.println(eAnswer + " " + lAnswer);
	}
}