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 scan =new Scanner(System.in);
String R=scan.next();
double r=Double.parseDouble(R);
double a=r*r*3.141592653589;
double b=r*2.0*3.141592653589;
System.out.printf("%f %f\n",a,b);
}
}