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 {
    Scanner sc = new Scanner(System.in);
    public void run() {
        double r=sc.nextDouble();
        ln(String.format("%.8f %8f",Math.PI*r*r, Math.PI*2*r));
    }
 
    public static void main(String[] args) {
        new Main().run();
    }
 
    public static void pr(Object o) {
        System.out.print(o);
    }
 
    public static void ln(Object o) {
        System.out.println(o);
    }
    public static void ln() {
        System.out.println();
    }
}