Square Triangle (I was bored in school)

main.rs

use std::num::NonZeroU64;

fn main() {
    triangle(40);
    cube(40);
}

fn cube(size: u64) {
    match NonZeroU64::new(size) {
        Some(_) => {},
        None => {
            println!("Invalid size");
            return
        }
    };
    for _ in 0..size {
        println!("{}", "*".repeat(size as usize));
    }
}

fn triangle(size: u64) {
    match NonZeroU64::new(size) {
        Some(_) => {},
        None => {
            println!("Invalid size");
            return
        }
    };
    for row in 0..size {
        println!("{}{}", " ".repeat(((size - row) /2) as usize), "*".repeat((row as usize) + 1));
    }
}