66 lines
1.9 KiB
Rust
66 lines
1.9 KiB
Rust
use std::{
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fs::File,
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io::{BufRead, BufReader},
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};
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enum State {
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Parsing,
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Moving,
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}
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fn main() -> () {
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let path = "input.txt";
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let input = File::open(path).unwrap();
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let buf = BufReader::new(input);
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let stack_char_width = 4;
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let mut stacks = Vec::<Vec<String>>::new();
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let mut state = State::Parsing;
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for line in buf.lines() {
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let line = line.unwrap();
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match state {
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State::Parsing => {
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if stacks.len() == 0 {
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for _ in 0..(line.len() + 1) / stack_char_width {
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stacks.push(Vec::new());
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}
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}
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if line != "" {
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for i in 0..stacks.len() {
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let idx = i * stack_char_width + 1;
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let char = &line[idx..idx + 1];
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if char != " " {
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stacks[i].push(char.to_owned());
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}
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}
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} else {
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state = State::Moving;
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for stack in &mut stacks {
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stack.pop();
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stack.reverse();
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}
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}
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}
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State::Moving => {
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let tokens = line
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.split(' ')
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.filter_map(|tok| tok.parse::<usize>().ok())
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.collect::<Vec<_>>();
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let mut tmp = Vec::<String>::new();
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for _ in 0..tokens[0] {
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tmp.push(stacks[tokens[1] - 1].pop().unwrap());
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}
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tmp.reverse();
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stacks[tokens[2] - 1].append(&mut tmp);
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}
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};
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}
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println!(
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"{}",
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stacks.into_iter().fold(String::from(""), |acc, mut stack| {
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acc + &stack.pop().unwrap()
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})
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);
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}
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