91 lines
2.2 KiB
Rust
91 lines
2.2 KiB
Rust
|
use std::collections::VecDeque;
|
||
|
|
use std::fmt::Write;
|
||
|
|
|
||
|
|
use aoc::err;
|
||
|
|
use aoc::Result;
|
||
|
|
|
||
|
|
use crate::intcode::{parse_memory, Intcode};
|
||
|
|
|
||
|
|
const INPUT: &str = include_str!("../input/day07.txt");
|
||
|
|
|
||
|
|
pub fn run() -> Result<String> {
|
||
|
|
let mut res = String::with_capacity(128);
|
||
|
|
|
||
|
|
writeln!(res, "part 1: {}", part1(INPUT)?)?;
|
||
|
|
|
||
|
|
Ok(res)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn permutations_rec(used: &mut Vec<i64>, available: &mut VecDeque<i64>, res: &mut Vec<Vec<i64>>) {
|
||
|
|
if available.is_empty() {
|
||
|
|
res.push(used.clone());
|
||
|
|
} else {
|
||
|
|
for _ in 0..available.len() {
|
||
|
|
used.push(available.pop_front().unwrap());
|
||
|
|
permutations_rec(used, available, res);
|
||
|
|
available.push_back(used.pop().unwrap());
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
fn permutations(array: &[i64]) -> Vec<Vec<i64>> {
|
||
|
|
let mut res = Vec::new();
|
||
|
|
|
||
|
|
permutations_rec(
|
||
|
|
&mut Vec::new(),
|
||
|
|
&mut VecDeque::from(array.to_vec()),
|
||
|
|
&mut res,
|
||
|
|
);
|
||
|
|
|
||
|
|
res
|
||
|
|
}
|
||
|
|
|
||
|
|
fn part1(input: &str) -> Result<i64> {
|
||
|
|
let memory = parse_memory(input)?;
|
||
|
|
|
||
|
|
let combinations = permutations(&[0, 1, 2, 3, 4]);
|
||
|
|
|
||
|
|
let mut res = 0;
|
||
|
|
for combination in combinations {
|
||
|
|
let mut output = 0;
|
||
|
|
for phase in combination.iter() {
|
||
|
|
let mut intcode = Intcode::with_memory(memory.clone());
|
||
|
|
|
||
|
|
intcode.add_input(*phase);
|
||
|
|
intcode.add_input(output);
|
||
|
|
|
||
|
|
intcode.run()?;
|
||
|
|
|
||
|
|
output = intcode
|
||
|
|
.get_day05_output()
|
||
|
|
.ok_or_else(|| err!("no output at end of pipeline!"))?;
|
||
|
|
}
|
||
|
|
|
||
|
|
res = std::cmp::max(res, output);
|
||
|
|
}
|
||
|
|
|
||
|
|
Ok(res)
|
||
|
|
}
|
||
|
|
|
||
|
|
#[cfg(test)]
|
||
|
|
mod tests {
|
||
|
|
use super::*;
|
||
|
|
|
||
|
|
const PROVIDED1: &str = "3,15,3,16,1002,16,10,16,1,16,15,15,4,15,99,0,0";
|
||
|
|
const PROVIDED2: &str =
|
||
|
|
"3,23,3,24,1002,24,10,24,1002,23,-1,23,101,5,23,23,1,24,23,23,4,23,99,0,0";
|
||
|
|
const PROVIDED3: &str = "3,31,3,32,1002,32,10,32,1001,31,-2,31,1007,31,0,33,1002,33,7,33,1,33,31,31,1,32,31,31,4,31,99,0,0,0";
|
||
|
|
|
||
|
|
#[test]
|
||
|
|
fn part1_provided() {
|
||
|
|
assert_eq!(part1(PROVIDED1).unwrap(), 43210);
|
||
|
|
assert_eq!(part1(PROVIDED2).unwrap(), 54321);
|
||
|
|
assert_eq!(part1(PROVIDED3).unwrap(), 65210);
|
||
|
|
}
|
||
|
|
|
||
|
|
#[test]
|
||
|
|
fn part1_real() {
|
||
|
|
assert_eq!(part1(INPUT).unwrap(), 844468);
|
||
|
|
}
|
||
|
|
}
|