pub fn pt1(input: &str) -> usize {
    let elems = input
        .lines()
        .filter_map(|l| l.split_once("   "))
        .map(|(l, r)| (l.parse::<usize>(), r.parse::<usize>()))
        .filter(|(l, r)| l.is_ok() && r.is_ok())
        .map(|(l, r)| (l.unwrap(), r.unwrap()));
    let mut lefts = elems.clone().map(|(l, _)| l).collect::<Vec<_>>();
    let mut rights = elems.map(|(_, r)| r).collect::<Vec<_>>();
    lefts.sort_unstable();
    rights.sort_unstable();
    lefts
        .iter()
        .zip(rights.iter())
        .map(|(l, r)| l.abs_diff(*r))
        .sum()
}
pub fn pt2(input: &str) -> usize {
    let elems = input
        .lines()
        .filter_map(|l| l.split_once("   "))
        .map(|(l, r)| (l.parse::<usize>(), r.parse::<usize>()))
        .filter(|(l, r)| l.is_ok() && r.is_ok())
        .map(|(l, r)| (l.unwrap(), r.unwrap()));
    let lefts = elems.clone().map(|(l, _)| l);
    let rights = elems.map(|(_, r)| r).collect::<Vec<_>>();
    lefts
        .map(|l| rights.clone().iter().filter(|r| **r == l).count() * l)
        .sum()
}

#[cfg(test)]
mod tests {
    use std::fs::read_to_string;

    use super::{pt1, pt2};

    #[test]
    pub fn test_pt1() {
        let input =
            read_to_string("./inputs/day01/example.txt").expect("Missing example.txt for day01");
        assert_eq!(pt1(&input), 11)
    }
    #[test]
    pub fn test_pt2() {
        let input =
            read_to_string("./inputs/day01/example.txt").expect("Missing example.txt for day01");

        assert_eq!(pt2(&input), 31)
    }
}