50 lines
1.3 KiB
Rust
50 lines
1.3 KiB
Rust
#![feature(test)]
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use regex::Regex;
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struct Policy {
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a: u32,
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b: u32,
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c: char,
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}
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type Input = Vec<(Policy, String)>;
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fn setup(input: &str) -> Input {
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let mut out: Input = Vec::new();
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let regex = Regex::new(r"^(\d+)-(\d+) (.): (\w+)$").unwrap();
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for line in input.lines() {
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let result = regex.captures(line).unwrap();
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let a = result[1].parse::<u32>().unwrap();
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let b = result[2].parse::<u32>().unwrap();
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let c = result[3].parse::<char>().unwrap();
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let password = result[4].to_string();
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out.push((Policy { a, b, c }, password));
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}
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out
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}
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fn part1(input: &Input) -> String {
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let mut out: u32 = 0;
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for (policy, password) in input {
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let count = password.chars().filter(|c| c == &policy.c).count() as u32;
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if policy.a <= count && count <= policy.b {
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out += 1;
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}
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}
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out.to_string()
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}
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fn part2(input: &Input) -> String {
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let mut out: u32 = 0;
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for (policy, password) in input {
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let a = password.chars().nth(policy.a as usize - 1).unwrap();
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let b = password.chars().nth(policy.b as usize - 1).unwrap();
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if (a == policy.c) ^ (b == policy.c) {
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out += 1;
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}
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}
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out.to_string()
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}
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aoc::main!(2020, 2, ex: 1);
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