import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    } main {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) int l = Integer.parseInt(scanner.next()); l Integer.parseInt(scanner.next()) Integer.parseInt Integer scanner.next() scanner.next scanner double x; x x = (double)l/3.0 x (double)l/3.0 (double)l 3.0 System.out.println(Math.pow(x, 3)) System.out.println System.out System System.out Math.pow(x, 3) Math.pow Math x 3 String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int l = Integer.parseInt(scanner.next());
        double x;
        x = (double)l/3.0;
        System.out.println(Math.pow(x, 3));
    }
}