fn fish(a: &[i64], b: &[i64]) -> i64 {
    let size = a.len();
    let mut dead = 0i64;
    let mut fish: Vec<i64> = Vec::new();

    for i in 0..size {
        if b[i] == 1 {
            fish.push(a[i]);
        } else if !fish.is_empty() {
            while let Some(&last) = fish.last() {
                dead += 1;
                if a[i] > last {
                    fish.pop();
                } else {
                    break;
                }
            }
        }
    }

    size as i64 - dead
}