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#![allow(dead_code)]
#![allow(unused_variables)]
use advent_of_code::prelude::*;
#[derive(Default)]
pub struct WrappingQueue {
queue: Vec<(usize, isize)>,
}
impl std::fmt::Debug for WrappingQueue {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_list()
.entries(self.queue.iter().copied().map(|v| v.1))
.finish()
}
}
impl WrappingQueue {
fn mix(&mut self, idx: usize) {
let val = self.queue.remove(idx);
let new_idx: usize = ((idx as isize + val.1)
.rem_euclid(self.queue.len() as isize))
.try_into()
.unwrap();
self.queue.insert(new_idx, val);
}
}
pub fn parse(fh: File) -> Result<WrappingQueue> {
Ok(WrappingQueue {
queue: parse::lines(fh).enumerate().collect(),
})
}
pub fn part1(mut q: WrappingQueue) -> Result<isize> {
for i in 0..q.queue.len() {
let idx = q.queue.iter().position(|(idx, _)| *idx == i).unwrap();
q.mix(idx);
}
let zero_idx = q.queue.iter().position(|(_, val)| *val == 0).unwrap();
Ok(q.queue[(zero_idx + 1000) % q.queue.len()].1
+ q.queue[(zero_idx + 2000) % q.queue.len()].1
+ q.queue[(zero_idx + 3000) % q.queue.len()].1)
}
pub fn part2(q: WrappingQueue) -> Result<isize> {
let key = 811589153;
let mut q = WrappingQueue {
queue: q.queue.into_iter().map(|(i, v)| (i, key * v)).collect(),
};
for _ in 0..10 {
for i in 0..q.queue.len() {
let idx = q.queue.iter().position(|(idx, _)| *idx == i).unwrap();
q.mix(idx);
}
}
let zero_idx = q.queue.iter().position(|(_, val)| *val == 0).unwrap();
Ok(q.queue[(zero_idx + 1000) % q.queue.len()].1
+ q.queue[(zero_idx + 2000) % q.queue.len()].1
+ q.queue[(zero_idx + 3000) % q.queue.len()].1)
}
#[test]
fn test() {
assert_eq!(
part1(parse(parse::data(2022, 20).unwrap()).unwrap()).unwrap(),
17490
);
assert_eq!(
part2(parse(parse::data(2022, 20).unwrap()).unwrap()).unwrap(),
1632917375836
);
}
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