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 Rust (1.15.1) (judge verdict: Accepted)


use std::io;

fn solve(){
    let mut buf = String::new();
    io::stdin().read_line(&mut buf).unwrap();
    let mut l = buf.trim().parse::<i32>().unwrap();
    let res = (l as f64)/3f64;
    println!("{}",res*res*res);
}


fn main(){
    let mut t_cases = 1;
    // let mut buf = String::new();
    // io::stdin().read_line(&mut buf);
    // t_cases = buf.trim().parse::<i32>();
    for _ in 0..t_cases{
        solve();
    }
}