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|
use aoc;
use std::io::{BufRead, BufReader, Read};
use aoc::Day;
use regex::Regex;
struct Day4 {}
enum Direction {
Horizontal,
Vertical,
DiagonalDown,
DiagonalUp,
}
impl Day4 {
fn parse_input(&self, input: BufReader<Box<dyn Read>>) -> Vec<String> {
input
.lines()
.map(|l| {
l
.unwrap()
.trim()
.to_string()
})
.collect::<Vec<String>>()
}
fn _diagonal_half_loop(&self, input: &Vec<String>) -> Vec<String> {
let mut out: Vec<String> = vec![];
for y in 0..input.len() {
let mut out_row = String::new();
for (x, row) in input[0..y + 1].iter().rev().enumerate() {
out_row.push(row.chars().nth(x).unwrap());
}
out.push(out_row)
}
out
}
fn _rotate(&self, input: &Vec<String>) -> Vec<String> {
let mut output: Vec<String> = vec![];
for (i, _) in input[0].char_indices() {
let mut line_out = String::new();
for line in input {
let a = line.chars().nth(i).unwrap();
line_out.push(a)
}
output.push(line_out.chars().rev().collect::<String>());
}
output
}
fn _mirror(&self, input: &Vec<String>) -> Vec<String> {
input
.iter()
.map(|l| {
l
.chars()
.rev()
.collect::<String>()
})
.collect::<Vec<String>>()
}
fn diagonal_loop(&self, input: &Vec<String>) -> Vec<String> {
let mut first_half: Vec<String> = self._diagonal_half_loop(input);
let rev_input = input
.iter()
.rev()
.map(|row| {
row
.chars()
.rev()
.collect::<String>()
})
.collect::<Vec<String>>();
let mut second_half = self
._diagonal_half_loop(&rev_input)
.iter()
.rev()
.collect::<Vec<_>>()[1..]
.iter()
.map(|row| {
row
.chars()
.rev()
.collect::<String>()
})
.collect::<Vec<String>>();
first_half.append(&mut second_half);
first_half
}
fn loop_over_puzzle(&self, input: &Vec<String>, direction: Direction, rev: bool) -> Vec<String> {
let _input = if rev {
self._rotate(&self._rotate(&input))
} else {
input.clone()
};
match direction {
Direction::Horizontal => _input,
Direction::Vertical => self._mirror(&self._rotate(&_input)),
Direction::DiagonalUp => self.diagonal_loop(&_input),
Direction::DiagonalDown => self.diagonal_loop(&self._rotate(&_input)),
}
}
}
impl Day for Day4 {
fn example_input(&self) -> &'static str {
r#"
MMMSXXMASM
MSAMXMSMSA
AMXSXMAAMM
MSAMASMSMX
XMASAMXAMM
XXAMMXXAMA
SMSMSASXSS
SAXAMASAAA
MAMMMXMMMM
MXMXAXMASX
"#.trim()
// r#"
// 123
// 456
// 789
// "#.trim()
}
fn example_result_part_1(&self) -> &'static str {
"18"
}
fn example_result_part_2(&self) -> &'static str {
"9"
}
fn part_1(&self, input: BufReader<Box<dyn Read>>) -> String {
let puzzle = self.parse_input(input);
let mut all_possibilities: Vec<String> = vec![];
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::Horizontal, false));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::Horizontal, true));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::Vertical, false));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::Vertical, true));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::DiagonalUp, false));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::DiagonalUp, true));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::DiagonalDown, false));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::DiagonalDown, true));
let re = Regex::new("XMAS");
all_possibilities
.into_iter()
.map(|l| {
re
.clone()
.unwrap()
.find_iter(&l)
.count()
})
.sum::<usize>()
.to_string()
}
fn part_2(&self, input: BufReader<Box<dyn Read>>) -> String {
let puzzle = self.parse_input(input);
let mut all_possibilities: Vec<String> = vec![];
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::DiagonalUp, false));
all_possibilities.append(&mut self.loop_over_puzzle(&puzzle, Direction::DiagonalDown, false));
let re = Regex::new("MAS|SAM");
all_possibilities
.into_iter()
.map(|l| {
re
.clone()
.unwrap()
.find_iter(&l)
.map(|m| println!("{:#?}", m))
.count()
})
.sum::<usize>()
.to_string()
}
}
fn main() {
aoc::main(&Day4 {});
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_day4() {
aoc::test_day(&Day4 {});
}
}
|
