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use regex::Regex;
const INPUT_FILE: &str = "input";
fn p1(input: &str) {
let re = Regex::new(r"mul\(([0-9]{1,3}),([0-9]{1,3})\)").unwrap();
let mut result: u32 = 0;
for (_, [x, y]) in re.captures_iter(input).map(|m| m.extract()) {
result += x.parse::<u32>().unwrap() * y.parse::<u32>().unwrap();
}
println!("Result: {}", result);
}
fn p2(input: &str) {
let re = Regex::new(r"do\(\)|don't\(\)|mul\(([0-9]{1,3}),([0-9]{1,3})\)").unwrap();
let mut doing = true;
let mut result: u32 = 0;
for m in re.captures_iter(input) {
let mut it = m.iter();
match it.next().unwrap().map(|m| m.as_str()) {
Some("do()") => doing = true,
Some("don't()") => doing = false,
Some(mul) if doing && mul.starts_with("mul") => {
if let [x, y] = it
.flatten()
.map(|m| m.as_str().parse::<u32>().unwrap())
.collect::<Vec<u32>>()[..]
{
result += x * y;
}
}
_ => (),
}
}
println!("Result: {}", result);
}
fn main() {
let input = std::fs::read_to_string(INPUT_FILE).unwrap();
p1(&input);
p2(&input);
}
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