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: Wrong Answer)

import java.util.*;
import java.lang.*;
import java.io.*;
import java.math.*;

class Main
{
    static BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
    static int tc=1;
    static String[] s;

    public static long[] ila(String[] s){
        long[] array=new long[s.length];
        for(int i=0;i<array.length;i++)
            array[i]=Long.parseLong(s[i]);
        return array;
    }
    public static void main (String[] args) throws java.lang.Exception
    {
        tc=1;
        t:
        for(int z=1;z<=tc;z++){
        	int L = Integer.parseInt(br.readLine());
        	int length = L/3;
        	L-=length;
        	int breadth = L/2;
        	int height = L - breadth;
        	System.out.print((long)length*breadth*height+".000000000000");
        }
    }
}