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 ToiN implements Toi{
	public void exec(String[] args){
		solve();
	}
	public void solve(){
	
	}
}
  */

interface Toi {
	public void exec(String[] args);
}

public class Main {
	public static void main(String[] args) {
		Toi toi = new Toi14();
		toi.exec(args);
	}
}

class Tool {
	public void inputArray(int[] array) {
		Scanner sc = new Scanner(System.in);
		for (int i = 0; i < array.length; i++) {
			try {
				array[i] = sc.nextInt();
			} catch (Exception e) {
				break;
			}
		}
	}
}

class Toi8 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		Scanner sc = new Scanner(System.in);
		int[] whxyr = new int[5];
		for (byte i = 0; i < whxyr.length; i++) {
			whxyr[i] = sc.nextInt();
		}
		calc(whxyr);
		int[] renewWh = {whxyr[0] - whxyr[4], whxyr[1] - whxyr[4], whxyr[2] + whxyr[4], whxyr[3] + whxyr[4]};
		if (renewWh[0] >= 0 && renewWh[1] >= 0 && renewWh[2] <= whxyr[0] && renewWh[3] <= whxyr[1]) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		}
	}
	
	public int[] calc(int[] array) {
		int tmp;
		for (byte i = 0; i < array.length - 2; i++) {
			if (array[i + 2] < 0) {
				tmp = array[i];
				array[i] = array[i + 2];
				array[i + 2] = tmp;
			}
		}
		return array;
	}
}

class Toi9 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		for (short i = 0; i < 1000; i++) {
			System.out.println("Hello World");
		}
	}
}

class Toi10 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		short[] tmp = new short[10000];
		Scanner sc = new Scanner(System.in);
		for (short i = 0; i < 10000; i++) {
			try {
				tmp[i] = sc.nextShort();
				if (tmp[i] == 0) {
					break;
				}
			} catch (Exception e) {
				break;
			}
		}
		for (short i = 1; i <= 10000; i++) {
			if (tmp[i - 1] == 0) {
				break;
			}
			System.out.println("Case " + i + ": " + tmp[i - 1]);
		}
	}
}

class Toi11 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		short[] xy = new short[6000];
		Scanner sc = new Scanner(System.in);
		short point = 0;
		for (short i = 0; i < 3000; i++) {
			try {
				xy[i] = sc.nextShort();
				xy[i + 3000] = sc.nextShort();
			} catch (Exception e) {
				break;
			}
			if (xy[i] == 0 && xy[i + 3000] == 0) {
				point = i;
				break;
			}
		}
		for (short i = 1; i <= point; i++) {
			if (xy[i - 1] < xy[i + 3000 - 1]) {
				System.out.println(xy[i - 1] + " " + xy[i + 3000 - 1]);
			} else {
				System.out.println(xy[i + 3000 - 1] + " " + xy[i - 1]);
			}
		}
	}
}

class Toi12 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		short[] abc = new short[5];
		Scanner sc = new Scanner(System.in);
		for (byte i = 0; i < 3; i++) {
			abc[i] = sc.nextShort();
		}
		short[] f = new short[5000];
		for (short i = 0; i < 5000; i++) {
			f[i] = 0;
		}
		calc(abc[2], f);
		short count = 0;
		for (short i = 0; i < 5000; i++) {
			if (f[i] >= abc[0] && f[i] <= abc[1]) {
				count++;
			} else {
				continue;
			}
		}
		System.out.println(count);
	}
	
	public void calc(short inputNum, short[] outputArray) {
		for (short i = 1, j = 0; i <= inputNum; i++) {
			if (inputNum % i == 0) {
				outputArray[j] = i;
				j++;
			}
		}
	}
}

class Toi13 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		int[] ab = new int[2];
		Tool tool = new Tool();
		tool.inputArray(ab);
		double[] cd = {ab[0], ab[1]};
		System.out.print(ab[0] / ab[1] + " " + ab[0] % ab[1] + " ");
		System.out.printf("%.5f\n",cd[0]/cd[1]);
	}
}

class Toi14 implements Toi {
	public void exec(String[] args) {
		solve();
	}
	
	public void solve() {
		double r = (new Scanner(System.in).nextDouble());
		System.out.printf("%.6f",Math.pow(r,2) * Math.PI);
		System.out.print(" ");
		System.out.printf("%.6f\n",r * 2. * Math.PI);
	}
}