#[path = "../lib.rs"]
mod lib;

fn parse_line(line: &str) -> Vec<u64> {
    return line
        .split_whitespace()
        .skip(1)
        .map(|s| s.parse().unwrap())
        .collect();
}

fn count_games(times: &Vec<u64>, dists: &Vec<u64>) -> u64 {
    let mut results = vec![];

    for i in 0..times.len() {
        // how many integer x can satisfy
        // (times[i] - x) * x > dists[i]
        let p = (times[i] as f64) / 2.0;
        let q = p * p - (dists[i] as f64);
        assert!(q >= 0.0);
        let q2 = q.sqrt();
        assert!(q2 < p);
        let x1 = (p - q2).floor() as u64;
        let x2 = (p + q2).ceil() as u64;
        results.push(x2 - x1 - 1);
    }

    return results.iter().product();
}

fn main() {
    let mut lines = lib::iter_input();
    let line1 = lines.next().unwrap();
    let line2 = lines.next().unwrap();

    let times1 = parse_line(&line1);
    let dists1 = parse_line(&line2);

    let times2 = parse_line(&line1.replace(" ", "").replace(":", ": "));
    let dists2 = parse_line(&line2.replace(" ", "").replace(":", ": "));

    println!("part2: {}", count_games(&times1, &dists1));
    println!("part2: {}", count_games(&times2, &dists2));
}