fn main() {
    let a = 2;
    let b = 3;
    print_number(a + b);
    print_number(add(a, b));
    print_number(a + b);

    print_number(b - a);
    print_number(sub(b, a));
    print_number(b - a);

    print_number(a - b);
    print_number(sub(a, b));
    print_number(a - b);
}

fn add(a: int, b: int): int {
    return a + b;
}

fn sub(a: int, b: int): int {
    return a - b;
}