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 C# (judge verdict: Accepted)

using System;
using System.Collections;
class main{
	public static void Main(){
		double r = double.Parse(Console.ReadLine());
		double S, C;
		S = Math.Pow(r, 2) * Math.PI;
		C = 2 * r * Math.PI;
		Console.WriteLine("{0} {1}", S.ToString("F6"), C.ToString("F6"));
	}
}