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#![allow(dead_code)]
#![allow(unused_variables)]
use advent_of_code::prelude::*;
#[derive(Default)]
pub struct Pile(Vec<char>);
impl Pile {
fn move_from(&mut self, other: &mut Self, n: usize) {
for _ in 0..n {
self.0.push(other.0.pop().unwrap());
}
}
fn unshift(&mut self, c: char) {
self.0.insert(0, c);
}
fn push(&mut self, c: char) {
self.0.push(c);
}
fn pop(&mut self) -> Option<char> {
self.0.pop()
}
fn top(&self) -> Option<char> {
self.0.last().copied()
}
}
struct Instruction {
count: usize,
from: usize,
to: usize,
}
pub struct Crates {
piles: Vec<Pile>,
instructions: Vec<Instruction>,
}
pub fn parse(fh: File) -> Result<Crates> {
let mut lines = parse::raw_lines(fh);
let mut piles: Vec<Pile> = vec![];
for line in lines.by_ref() {
if line.starts_with(" 1 ") {
break;
}
let pile_count = (line.len() + 1) / 4;
piles.resize_with(pile_count, Default::default);
for (pile_idx, pile) in piles.iter_mut().enumerate() {
let idx = pile_idx * 4;
assert!([' ', '['].contains(&line.chars().nth(idx).unwrap()));
let crate_name = line.chars().nth(idx + 1).unwrap();
if crate_name != ' ' {
pile.unshift(crate_name);
}
assert!([' ', ']'].contains(&line.chars().nth(idx + 2).unwrap()));
assert!([Some(' '), None].contains(&line.chars().nth(idx + 3)));
}
}
assert_eq!(lines.next().unwrap(), "");
let mut instructions = vec![];
for line in lines {
let captures = regex_captures!(
r"^move ([0-9]+) from ([0-9]+) to ([0-9]+)$",
&line
)
.unwrap();
let count = captures[1].parse().unwrap();
let from = captures[2].parse().unwrap();
let to = captures[3].parse().unwrap();
instructions.push(Instruction { count, from, to });
}
Ok(Crates {
piles,
instructions,
})
}
fn part1_str(mut crates: Crates) -> Result<String> {
for Instruction { count, from, to } in crates.instructions {
for _ in 0..count {
let c = crates.piles[from - 1].pop().unwrap();
crates.piles[to - 1].push(c);
}
}
Ok(crates
.piles
.iter()
.map(|pile| pile.top().unwrap())
.collect())
}
pub fn part1(crates: Crates) -> Result<i64> {
println!("{}", part1_str(crates)?);
Ok(0)
}
fn part2_str(mut crates: Crates) -> Result<String> {
for Instruction { count, from, to } in crates.instructions {
let mut tmp = vec![];
for _ in 0..count {
let c = crates.piles[from - 1].pop().unwrap();
tmp.push(c);
}
for c in tmp.iter().copied().rev() {
crates.piles[to - 1].push(c);
}
}
Ok(crates
.piles
.iter()
.map(|pile| pile.top().unwrap())
.collect())
}
pub fn part2(crates: Crates) -> Result<i64> {
println!("{}", part2_str(crates)?);
Ok(0)
}
#[test]
fn test() {
assert_eq!(
part1_str(parse(parse::data(2022, 5).unwrap()).unwrap()).unwrap(),
"PSNRGBTFT"
);
assert_eq!(
part2_str(parse(parse::data(2022, 5).unwrap()).unwrap()).unwrap(),
"BNTZFPMMW"
);
}
|
