black box

State::new.rs

impl State {
    fn new(valves: &[Valve]) -> Self {
        // let valve_states = black_box(valves)
        //     .iter()
        //     .map(|valve| valve.rate == 0)
        //     .collect();

        let mut valve_states = Vec::with_capacity(black_box(valves).len()); // Fast
        for valve in valves {
            valve_states.push(black_box(valve).rate == 0);
        }

        let valve_states = black_box(valve_states);
        State {
            valve_states,
            position: 0,
            rate: 0,
            released_pressure: 0,
        }
    }

    ...
}