Problem:
Score : 300 points

Problem Statement

Given is a positive integer L.
Find the maximum possible volume of a rectangular cuboid whose sum of the dimensions (not necessarily integers) is L.

Constraints

1 ≤ L ≤ 1000

L is an integer.

Input

Input is given from Standard Input in the following format:

L

Output

Print the maximum possible volume of a rectangular cuboid whose sum of the dimensions (not necessarily integers) is L.
Your output is considered correct if its absolute or relative error from our answer is at most 10^{-6}.

Sample Input 1

3

Sample Output 1

1.000000000000

For example, a rectangular cuboid whose dimensions are 0.8, 1, and 1.2 has a volume of 0.96.

On the other hand, if the dimensions are 1, 1, and 1, the volume of the rectangular cuboid is 1, which is greater.

Sample Input 2

999

Sample Output 2

36926037.000000000000

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;
import java.io.*;
public class Main
{
    public static void main(String args[])throws Exception
    {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); 
        PrintWriter pw=new PrintWriter(System.out);
        double max=-1;
        int dim=Integer.parseInt(br.readLine());
        //if(dim==1)
        //pw.println("0.037026");
        //else if(dim==2)
    //    pw.println("0.296274");
     //   else
      //  {
            /*for(int i=1;i<=1000;i++)
            {
                for(int j=1;j<=1000;j++)
                {
                    for(int k=1;k<=1000;k++)
                    {
                        if(i+j+k==dim)
                        {
                            max=Math.max(max,(double)i*j*k);
                        }
                    }
                }
            }*/
            pw.println(Math.pow((double)dim/3,3));
        //}
        //System.out.println(max);
        pw.flush();
        pw.close();
    }
}