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#![allow(dead_code)]
#![allow(unused_variables)]
#![allow(unused_mut)]
use regex::Regex;
use std::env;
use std::fs::File;
use std::io::Read;

fn main() {
    let args: Vec<String> = env::args().collect();
    let filename = if args.len() == 1 {
        "in/".to_owned() + args[0].split('/').last().unwrap() + ".pzl"
    } else {
        args[1].clone()
    };
    let mut f = File::open(filename).expect("cannot open file");
    let mut content = String::new();
    f.read_to_string(&mut content).expect("cannot read file");
    let lines = content.trim_end().split("\n");

    let re = Regex::new(r"mul\((?<a>[0-9]+),(?<b>[0-9]+)\)").unwrap();
    let mut res1 = 0;
    for line in lines.clone() {
        res1 += re
            .captures_iter(line)
            .map(|caps| {
                let p = |name| caps.name(name).unwrap().as_str().parse::<i32>().unwrap();
                p("a") * p("b")
            })
            .fold(0, |a, b| a + b);
    }

    let re_m = Regex::new(r"^mul\((?<a>[0-9]+),(?<b>[0-9]+)\)").unwrap();
    let re_do = Regex::new(r"^do\(\)").unwrap();
    let re_dont = Regex::new(r"^don't\(\)").unwrap();
    let mut res2 = 0;
    let mut valid = true;
    for line in lines {
        for i in 0..line.len() {
            if re_do.is_match(&line[i..]) {
                valid = true;
            } else if re_dont.is_match(&line[i..]) {
                valid = false;
            } else if valid && re_m.is_match(&line[i..]) {
                let cap = re_m.captures(&line[i..]).unwrap();
                let p = |name| cap.name(name).unwrap().as_str().parse::<i32>().unwrap();
                res2 += p("a") * p("b");
            }
        }
    }

    println!("res1: {}", res1);
    println!("res2: {}", res2);
    assert_eq!(res1, 162813399);
    assert_eq!(res2, 53783319);
}