Advent of Code 2022 - Day 4

use lazy_static::lazy_static;
use regex::Regex;

fn full_inclusion_comparison(left: (i32, i32), right: (i32, i32)) -> bool {
    if (left.0 <= right.0 && left.1 >= right.1) || (right.0 <= left.0 && right.1 >= left.1) {
        true
    } else {
        false
    }
}

fn partial_inclusion_comparison(left: (i32, i32), right: (i32, i32)) -> bool {
    if (left.0 <= right.1) && (right.0 <= left.1) {
        true
    } else {
        false
    }
}

lazy_static! {
    static ref RE: Regex = Regex::new(r"\d+").unwrap();
}

fn parse_line(line: &str) -> ((i32, i32), (i32, i32)) {
    let mut found = RE.find_iter(&line);
    let left: (i32, i32) = (
        found.next().unwrap().as_str().parse().unwrap(),
        found.next().unwrap().as_str().parse().unwrap(),
    );
    let right: (i32, i32) = (
        found.next().unwrap().as_str().parse().unwrap(),
        found.next().unwrap().as_str().parse().unwrap(),
    );
    (left, right)
}

pub fn part_one(input: &str) -> Option<u32> {
    let mut overlaps: u32 = 0;
    for line in input.lines() {
        let (left, right) = parse_line(line);
        if full_inclusion_comparison(left, right) {
            overlaps += 1;
        }
    }
    Some(overlaps)
}

pub fn part_two(input: &str) -> Option<u32> {
    let mut overlaps: u32 = 0;
    for line in input.lines() {
        let (left, right) = parse_line(line);
        if partial_inclusion_comparison(left, right) {
            overlaps += 1;
        }
    }
    Some(overlaps)
}