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.*;
import java.util.Scanner;
import java.util.Arrays;
import java.lang.Math;

class Main {
    static Scanner sc = new Scanner(System.in);
    public static void main(String[] args) throws IOException {
        double r = ReadDouble();
        String res1 = String.format("%.8f", r * r * Math.PI);
        String res2 = String.format("%.8f", 2 * r * Math.PI);
        System.out.println(res1 + " " + res2);
    }
    static int ReadInt() throws IOException {
        return Integer.parseInt(sc.next());
    }
    static double ReadDouble() throws IOException {
        return sc.nextDouble();
    }
}