#![allow(dead_code, deprecated, unused_variables, unused_mut)]
fn quadratic_mul<const N: usize>(a: [u8; N], b: [u8; N]) -> [u8; N] {
    let mut out = [0; N];
    for j in 0..N {
        let mut carry = 0;
        for i in 0..(N - j) {
            (out[j + i], carry) = u8::carrying_mul_add(a[i], b[j], out[j + i], carry);
        }
    }
    out
}
fn main() {
    assert_eq!(quadratic_mul([0xFF; 3], [0xFF; 3]), [1, 0, 0]);
    assert_eq!(u32::wrapping_mul(0x9e3779b9, 0x7f4a7c15), 0xcffc982d);
    assert_eq!(
        quadratic_mul(u32::to_le_bytes(0x9e3779b9), u32::to_le_bytes(0x7f4a7c15)),
        u32::to_le_bytes(0xcffc982d)
    );
}