import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    } main {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) int inputInt = scanner.nextInt(); inputInt scanner.nextInt() scanner.nextInt scanner double oneSide = inputInt / 3.0; oneSide inputInt / 3.0 inputInt 3.0 double answer = oneSide * oneSide * oneSide; answer oneSide * oneSide * oneSide oneSide * oneSide * oneSide oneSide oneSide oneSide System.out.println(answer) System.out.println System.out System System.out answer String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int inputInt = scanner.nextInt();
        double oneSide = inputInt / 3.0;
        double answer = oneSide * oneSide * oneSide;
        System.out.println(answer);
    }
}