From 65dd6da947a25fcd6905631f27926da0ab9df657 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tristan=20Dani=C3=ABl=20Maat?= <tm@tlater.net>
Date: Fri, 4 Dec 2020 21:34:49 +0000
Subject: [PATCH] Complete day 4.2
---
day-4/src/main.rs | 52 ++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 49 insertions(+), 3 deletions(-)
diff --git a/day-4/src/main.rs b/day-4/src/main.rs
index 3833cc0..1e5dfd9 100644
--- a/day-4/src/main.rs
+++ b/day-4/src/main.rs
@@ -17,12 +17,16 @@ fn parse_passports(input: &str) -> Result<Vec<HashMap<&str, &str>>, &str> {
.trim()
.split(|c| c == ' ' || c == '\n')
.map(|field| {
- let item = field.split_at(3);
+ let split = field
+ .find(':')
+ .ok_or("Invalid passport entry; no separator")?;
+ let item = field.split_at(split);
+
let key = item.0;
let value = item
.1
.strip_prefix(":")
- .ok_or("Invalid entry; value too short")?;
+ .expect("We've already checked the separator exists");
Ok((key, value))
})
@@ -33,13 +37,55 @@ fn parse_passports(input: &str) -> Result<Vec<HashMap<&str, &str>>, &str> {
fn validate_passports(passports: &Vec<HashMap<&str, &str>>) -> usize {
let required_fields = ["byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid"];
+ let rules = [
+ |year: &str| match year.parse() {
+ Ok(1920..=2002) => true,
+ _ => false,
+ },
+ |year: &str| match year.parse() {
+ Ok(2010..=2020) => true,
+ _ => false,
+ },
+ |year: &str| match year.parse() {
+ Ok(2020..=2030) => true,
+ _ => false,
+ },
+ |height: &str| match height.split_at(height.chars().count() - 2) {
+ (height, "cm") => match height.parse() {
+ Ok(150..=193) => true,
+ _ => false,
+ },
+ (height, "in") => match height.parse() {
+ Ok(59..=76) => true,
+ _ => false,
+ },
+ _ => false,
+ },
+ |color: &str| match color.split_at(1) {
+ ("#", code) => code.chars().all(|a| char::is_ascii_hexdigit(&a)),
+ _ => false,
+ },
+ |color: &str| {
+ ["amb", "blu", "brn", "gry", "grn", "hzl", "oth"]
+ .iter()
+ .any(|c| c == &color)
+ },
+ |pid: &str| pid.chars().count() == 9 && pid.chars().all(char::is_numeric),
+ ];
passports
.iter()
.filter(|passport| {
required_fields
.iter()
- .all(|field| passport.contains_key(field))
+ .zip(rules.iter())
+ .all(|(field, rule)| {
+ if let Some(value) = passport.get(field) {
+ rule(value)
+ } else {
+ false
+ }
+ })
})
.count()
}