diff --git a/src/lib.rs b/src/lib.rs index 681b2b1..566cd1e 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -1,75 +1,84 @@ -use aoc_runner_derive::{aoc_lib, aoc}; +use aoc_runner_derive::{aoc, aoc_generator, aoc_lib}; -#[aoc(day1, part1)] -pub fn solve_d1_p1(input: &str) -> u64 { +#[aoc_generator(day1)] +pub fn d1_input(input: &str) -> Vec { let mut entries: Vec = input.split('\n').map(|x| x.parse().unwrap()).collect(); entries.sort(); - for entry in &entries { + entries +} + +#[aoc(day1, part1)] +pub fn solve_d1_p1(input: &[u64]) -> u64 { + for entry in input { let needed = 2020 - entry; - if let Ok(idx) = entries.binary_search(&needed) { - return entry * entries[idx]; + if let Ok(idx) = input.binary_search(&needed) { + return entry * input[idx]; } } panic!("not found"); } #[aoc(day1, part2)] -pub fn solve_d1_p2(input: &str) -> Option { - let mut entries: Vec = input.split('\n').map(|x| x.parse().unwrap()).collect(); - entries.sort(); - for i in 0 .. entries.len()-2 { - let entry1 = entries[i]; - for j in i+1 .. entries.len()-1 { - let entry2 = entries[j]; +pub fn solve_d1_p2(input: &[u64]) -> Option { + for i in 0..input.len() - 2 { + let entry1 = input[i]; + for j in i + 1..input.len() - 1 { + let entry2 = input[j]; if entry1 + entry2 > 2020 { break; } - for k in j+1 .. entries.len() { - let entry3 = entries[k]; + for k in j + 1..input.len() { + let entry3 = input[k]; if entry1 + entry2 + entry3 == 2020 { - return Some(entry1 * entry2 * entry3) + return Some(entry1 * entry2 * entry3); } } } } - return None + return None; +} + +struct PasswdEntry<'a> { + lower_bound: usize, + upper_bound: usize, + policy_char: u8, + passwd: &'a [u8], +} + +impl<'a> PasswdEntry<'a> { + fn new(mut input: &'a str) -> Option { + let lb_idx = input.find('-')?; + let lower_bound: usize = (&input[..lb_idx]).parse().ok()?; + input = &input[lb_idx + 1..]; + + let ub_idx = input.find(' ')?; + let upper_bound: usize = (&input[..ub_idx]).parse().ok()?; + input = &input[ub_idx + 1..]; + + let policy_char = input.as_bytes()[0]; + let passwd = &input[3..].as_bytes(); + Some(PasswdEntry { lower_bound, upper_bound, policy_char, passwd }) + } } #[aoc(day2, part1)] pub fn solve_d2_p1(input: &str) -> usize { - fn line_is_valid(mut line: &str) -> bool { - let lb_idx = line.find('-').unwrap(); - let lb: usize = (&line[..lb_idx]).parse().unwrap(); - line = &line[lb_idx+1..]; - - let ub_idx = line.find(' ').unwrap(); - let ub: usize = (&line[..ub_idx]).parse().unwrap(); - line = &line[ub_idx+1..]; - - let letter = line.as_bytes()[0]; - let passwd = &line[3..]; - let count = passwd.bytes().filter(|&b| b == letter).count(); - count >= lb && count <= ub + fn line_is_valid(line: &str) -> bool { + let entry = PasswdEntry::new(line).unwrap(); + let count = entry.passwd.iter().filter(|&&b| b == entry.policy_char).count(); + (count >= entry.lower_bound) && (count <= entry.upper_bound) } input.split('\n').filter(|x| line_is_valid(x)).count() } #[aoc(day2, part2)] pub fn solve_d2_p2(input: &str) -> usize { - fn line_is_valid(mut line: &str) -> bool { - let lb_idx = line.find('-').unwrap(); - let lb: usize = (&line[..lb_idx]).parse().unwrap(); - line = &line[lb_idx+1..]; - - let ub_idx = line.find(' ').unwrap(); - let ub: usize = (&line[..ub_idx]).parse().unwrap(); - line = &line[ub_idx+1..]; - - let letter = line.as_bytes()[0]; - let passwd = &line[3..].as_bytes(); - (passwd[lb-1] == letter) ^ (passwd[ub-1] == letter) + fn line_is_valid(line: &str) -> bool { + let entry = PasswdEntry::new(line).unwrap(); + (entry.passwd[entry.lower_bound - 1] == entry.policy_char) + ^ (entry.passwd[entry.upper_bound - 1] == entry.policy_char) } input.split('\n').filter(|x| line_is_valid(x)).count() } -aoc_lib!{ year = 2020 } \ No newline at end of file +aoc_lib! { year = 2020 }