import java.util.Arrays;
import java.util.Collections;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    }

} import java.util.Arrays; Arrays java.util import java.util.Collections; Collections java.util import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    }

} Main public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    } main {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) double L = sc.nextDouble(); L sc.nextDouble() sc.nextDouble sc double k=Math.pow(L / 3, 3); k Math.pow(L / 3, 3) Math.pow Math L / 3 L 3 3 System.out.println(k) System.out.println System.out System System.out k String[] args args public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    }

} public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    }

} Main
import java.util.Arrays;
import java.util.Collections;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        double L = sc.nextDouble();

        double k=Math.pow(L / 3, 3);

        System.out.println(k);
    }

}
