Day 6, puzzle 2

This commit is contained in:
jazzpi 2022-12-13 16:56:25 +01:00
parent e3c356b1ac
commit a446a05c07
3 changed files with 14 additions and 6 deletions

View File

@ -2,7 +2,7 @@ use aoc22::{day6, util};
pub fn main() {
let input = util::parse_input();
let start = day6::parse_datastream(input.as_str());
let start = day6::parse_datastream(input.as_str(), 4);
println!("Datastream starts after {} characters", start + 1);
println!("Packet starts after {} characters", start + 1);
}

8
src/bin/d6p2.rs Normal file
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@ -0,0 +1,8 @@
use aoc22::{day6, util};
pub fn main() {
let input = util::parse_input();
let start = day6::parse_datastream(input.as_str(), 14);
println!("Message starts after {} characters", start + 1);
}

View File

@ -1,15 +1,15 @@
use std::collections::{HashSet, VecDeque};
pub fn parse_datastream(stream: &str) -> usize {
pub fn parse_datastream(stream: &str, n_distinct: usize) -> usize {
let mut chars: VecDeque<char> = VecDeque::new();
for (i, char) in stream.chars().enumerate() {
if i >= 4 {
if i >= n_distinct {
chars.pop_front();
}
chars.push_back(char);
if i >= 3 {
if i >= n_distinct - 1 {
let char_set: HashSet<char> = chars.iter().map(char::clone).collect();
if char_set.len() == 4 {
if char_set.len() == n_distinct {
return i;
}
}