91 lines
2.4 KiB
Rust
91 lines
2.4 KiB
Rust
use aoc_runner_derive::{aoc, aoc_generator};
|
|
|
|
#[derive(Debug, Eq, PartialEq)]
|
|
pub enum Direction {
|
|
Front,
|
|
Back,
|
|
Left,
|
|
Right,
|
|
}
|
|
|
|
#[aoc_generator(day5)]
|
|
pub fn input_generator(input: &str) -> Vec<Vec<Direction>> {
|
|
input
|
|
.lines()
|
|
.map(|line| {
|
|
line.chars()
|
|
.map(|c| match c {
|
|
'L' => Direction::Left,
|
|
'R' => Direction::Right,
|
|
'F' => Direction::Front,
|
|
'B' => Direction::Back,
|
|
other => panic!("Invalid direction: {}", other),
|
|
})
|
|
.collect()
|
|
})
|
|
.collect()
|
|
}
|
|
|
|
pub fn seat_to_pos(seat: &[Direction]) -> (usize, usize) {
|
|
let mut col_range: (usize, usize) = (0, 8);
|
|
let mut row_range: (usize, usize) = (0, 128);
|
|
for inst in seat {
|
|
let delta_col = (col_range.1 - col_range.0) / 2;
|
|
let delta_row = (row_range.1 - row_range.0) / 2;
|
|
match inst {
|
|
Direction::Back => {
|
|
row_range.0 += delta_row;
|
|
}
|
|
Direction::Front => {
|
|
row_range.1 -= delta_row;
|
|
}
|
|
Direction::Left => {
|
|
col_range.1 -= delta_col;
|
|
}
|
|
Direction::Right => {
|
|
col_range.0 += delta_col;
|
|
}
|
|
}
|
|
}
|
|
if row_range.1 - row_range.0 != 1 {
|
|
panic!("Invalid!");
|
|
}
|
|
if col_range.1 - col_range.0 != 1 {
|
|
panic!("Invalid!");
|
|
}
|
|
return (col_range.0, row_range.0);
|
|
}
|
|
|
|
#[aoc(day5, part1)]
|
|
pub fn solve_part1(input: &[Vec<Direction>]) -> usize {
|
|
let mut max_seat_id: usize = 0;
|
|
for seat in input {
|
|
let pos = seat_to_pos(seat);
|
|
let seat_id = pos.0 + pos.1 * 8;
|
|
max_seat_id = std::cmp::max(max_seat_id, seat_id);
|
|
}
|
|
return max_seat_id;
|
|
}
|
|
|
|
#[aoc(day5, part2)]
|
|
pub fn solve_part2(input: &[Vec<Direction>]) -> usize {
|
|
let mut seats = [[false; 8]; 128];
|
|
for seat in input {
|
|
let pos = seat_to_pos(seat);
|
|
seats[pos.1][pos.0] = true;
|
|
}
|
|
for id in 0..(8 * 128) {
|
|
let mut id = id;
|
|
let mut v = (false, false, false);
|
|
v.0 = seats[id / 8][id % 8];
|
|
id += 1;
|
|
v.1 = seats[id / 8][id % 8];
|
|
id += 1;
|
|
v.2 = seats[id / 8][id % 8];
|
|
if v == (true, false, true) {
|
|
return id - 1;
|
|
}
|
|
}
|
|
panic!("Something went wrong!");
|
|
}
|