AoC_2020/src/day5.rs

87 lines
2.3 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: &Vec<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<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<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!");
}