public/subjects/negative_spelling

negative_spelling

Instructions

In this exercise, you'll create the function neg_spell that will spell a negative number.

Here are some examples of what your function should return:

• -1 -> "minus one"
• -14 -> "minus fourteen"
• -348 -> "minus three hundred forty-eight"
• -1002 -> "minus one thousand two"

Only negative numbers will be accepted, up to "minus one million". If a positive number is passed the function should return "error: positive number".

Expected function

pub fn neg_spell(n: i64) -> String {

}

Usage

Here is a program to test your function.

use spelling::*;

fn main() {
    println!("{}", neg_spell(-1234));
    println!("{}", neg_spell(100));
}

And its output:

$ cargo run
minus one thousand two hundred thirty-four
error: positive number
$

Notions

• patterns