use std::iter::repeat;

fn power_level(x: i32, y: i32, serial: i32) -> i32 {
    let rack_id: i32 = x + 10;
    ((((rack_id * y + serial) * rack_id) / 100) % 10) - 5
}

fn main() {
    const SERIAL: i32 = 8141;

    let points: Vec<(i32, i32)> = (1..=300)
        .flat_map(|x| repeat(x).zip(1..=300))
        .collect();
    let power_levels: Vec<i32> = points
        .iter()
        .map(|(x, y)| power_level(*x, *y, SERIAL))
        .collect();

    assert_eq!(power_level(3, 5, 8), 4);
    assert_eq!(power_level(122, 79, 57), -5);
    assert_eq!(power_level(217, 196, 39), 0);
    assert_eq!(power_level(101, 153, 71), 4);
}