import java.io.FileNotFoundException;
import java.util.Scanner;

public class Main {
    @SuppressWarnings("deprecation")
	public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    }

} import java.io.FileNotFoundException; FileNotFoundException java.io import java.util.Scanner; Scanner java.util public class Main {
    @SuppressWarnings("deprecation")
	public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    }

} Main @SuppressWarnings("deprecation")
	public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    } main {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int L = sc.nextInt(); L sc.nextInt() sc.nextInt sc int POWL3 = L*L*L; POWL3 L*L*L L*L*L L L L double V = (double)POWL3/27; V (double)POWL3/27 (double)POWL3 27 System.out.println(String.format("%.8f", V)) System.out.println System.out System System.out String.format("%.8f", V) String.format String "%.8f" V String[] args args public class Main {
    @SuppressWarnings("deprecation")
	public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    }

} public class Main {
    @SuppressWarnings("deprecation")
	public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    }

} Main
import java.io.FileNotFoundException;
import java.util.Scanner;

public class Main {
    @SuppressWarnings("deprecation")
	public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	int L = sc.nextInt();

//    	BigDecimal POWL3 = new BigDecimal(L*L*L);
//
//    	BigDecimal ts = new BigDecimal(27);
//
//    	BigDecimal V = POWL3.di

    	int POWL3 = L*L*L;
    	double V = (double)POWL3/27;

    	System.out.println(String.format("%.8f", V));

    }

}