factorial.ark

[c] func printf(fmt: ^u8, ...) -> int;
[c] func scanf(fmt: ^u8, ...);

func factorial(n: int) -> int {
    if n == 0 {
        return 1;
    }
    return n * factorial(n - 1);
}

pub func main() -> int {
    number: int = 1;
    C::printf(c"Enter a number: \n");
    C::scanf("%d", &number);

    if number < 0 {
        C::printf(c"No negatives please\n");
        return -1;
    }

    result := factorial(number);
    C::printf(c"%d! = %d\n", number, result);
    return 0;
}