题解 | #牛牛的球#

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        double r = scanner.nextInt();
        double PI = 3.14;
        double s = 4.0 / 3 * PI * r * r * r;
        System.out.printf("%.2f", s);
    }
}