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;
 
class Main {
 
public static void main(String[] args) {
 
Scanner inp = new Scanner(System.in);
 
double r = inp.nextDouble();

System.out.printf("%.10f %.10f\n", Math.PI*Math.pow(r, 2), Math.PI*2*r );
 
}
}