#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::time::Duration;
fn main() {
    assert_eq!(
        Duration::new(0, 0).checked_add(Duration::new(0, 1)), Some(Duration::new(0, 1))
    );
    assert_eq!(Duration::new(1, 0).checked_add(Duration::new(u64::MAX, 0)), None);
}