public/subjects/count_factorial_steps

count_factorial_steps

Instructions

Create a function named count_factorial_steps that receives a factorial number and counts how many multiplications are necessary to have this number.

If the argument is not a factorial, or it is equal 0 or 1, then the function should return 0.

pub fn count_factorial_steps(factorial: u64) -> u64 {
}

As a reminder, the factorial of a number is the product of all the integers from 1 to that number.

Example: the factorial of 6 (written 6!) is 1 * 2 * 3 * 4 * 5 * 6 = 720.

Usage

Here is a possible program to test your function:

use count_factorial_steps::count_factorial_steps;

fn main() {
    println!("The factorial steps of 720 = {}", count_factorial_steps(720));
    println!("The factorial steps of 13 = {}", count_factorial_steps(13));
    println!("The factorial steps of 6 = {}", count_factorial_steps(6));
}

And its output:

$ cargo run
The factorial steps of 720 = 6
The factorial steps of 13 = 0
The factorial steps of 6 = 3