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 sc = new Scanner (System.in);
		//???????????? ??????r
		double r = sc.nextDouble();

		//???????°???
		double PI = 3.14;

		//??¢???????±??????? ?????? ?? ?????? ?? 3.14
		double Area = (r * r) * Math.PI;
		//?????¨????????? ?????? * 2 ??3.14
		double Circle = ( r * 2 ) * Math.PI;

		//??¨???
		System.out.printf("%.6f %.6f", Area,Circle);
	}
}