Format cardinal numbers in rust

formatcardinal.rs

fn cardinal_suffix(x: i64) -> &'static str {
    let last_digit = x % 10;
    let second_last_digit = x % 100 / 10;

    match (second_last_digit, last_digit) {
        (1, 1) => "th", // eleventh
        (_, 1) => "st", // first

        (1, 2) => "th", // twelfth
        (_, 2) => "nd", // second

        (1, 3) => "th", // thirteenth
        (_, 3) => "rd", // third

        (_, _) => "th", // fourth, fifth, sixth, seventh, eighth, ninth,
    }
}

fn format_cardinal(x: i64) -> String {
    format!("{}{}", x, cardinal_suffix(x))
}

fn main() {
    for i in 10..30 {
        println!("{}", format_cardinal(i));
    }
}