From ad9e6ed89631887e8feb36ebeee69160d3bbc7bd Mon Sep 17 00:00:00 2001 From: Curtis McEnroe Date: Wed, 7 Dec 2016 22:51:33 -0500 Subject: Day 7 part 2 --- src/bin/day07.rs | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 54 insertions(+), 3 deletions(-) (limited to 'src/bin') diff --git a/src/bin/day07.rs b/src/bin/day07.rs index 305fd8f..b4967ff 100644 --- a/src/bin/day07.rs +++ b/src/bin/day07.rs @@ -11,6 +11,26 @@ fn has_abba(s: &str) -> bool { }) } +fn abas(s: &str) -> Vec<&[u8]> { + s.as_bytes() + .windows(3) + .filter(|window| { + window[0] == window[2] + && window[0] != window[1] + }) + .collect() +} + +fn has_bab(s: &str, aba: &[u8]) -> bool { + s.as_bytes() + .windows(3) + .any(|window| { + window[0] == aba[1] + && window[1] == aba[0] + && window[2] == aba[1] + }) +} + #[derive(Default)] struct Ip { supernet: Vec, @@ -22,6 +42,17 @@ impl Ip { self.supernet.iter().any(|s| has_abba(s)) && !self.hypernet.iter().any(|s| has_abba(s)) } + + fn supports_ssl(&self) -> bool { + self.supernet + .iter() + .flat_map(|s| abas(s)) + .any(|aba| { + self.hypernet + .iter() + .any(|s| has_bab(s, aba)) + }) + } } impl FromStr for Ip { @@ -41,7 +72,7 @@ impl FromStr for Ip { } } -fn solve(input: &str) -> usize { +fn solve1(input: &str) -> usize { input.lines() .map(str::parse) .map(Result::unwrap) @@ -49,11 +80,20 @@ fn solve(input: &str) -> usize { .count() } +fn solve2(input: &str) -> usize { + input.lines() + .map(str::parse) + .map(Result::unwrap) + .filter(Ip::supports_ssl) + .count() +} + fn main() { let mut input = String::new(); io::stdin().read_to_string(&mut input).unwrap(); - println!("Part 1: {}", solve(&input)); + println!("Part 1: {}", solve1(&input)); + println!("Part 2: {}", solve2(&input)); } #[test] @@ -64,5 +104,16 @@ abcd[bddb]xyyx aaaa[qwer]tyui ioxxoj[asdfgh]zxcvbn "; - assert_eq!(2, solve(input.trim())); + assert_eq!(2, solve1(input.trim())); +} + +#[test] +fn part2() { + let input = " +aba[bab]xyz +xyx[xyx]xyx +aaa[kek]eke +zazbz[bzb]cdb +"; + assert_eq!(3, solve2(input.trim())); } -- cgit 1.4.1