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|
#![allow(dead_code)]
#![allow(unused_variables)]
use advent_of_code::prelude::*;
pub enum ModuleType {
Broadcast,
FlipFlop(bool),
Conjunction(HashMap<String, bool>),
}
pub struct Module {
name: String,
ty: ModuleType,
destinations: Vec<String>,
low_pulses: i64,
high_pulses: i64,
}
impl std::str::FromStr for Module {
type Err = anyhow::Error;
fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
let mut parts = s.split(" -> ");
let module_name = parts.next().unwrap();
let destinations = parts.next().unwrap();
let destinations: Vec<_> =
destinations.split(", ").map(|s| s.to_string()).collect();
let (ty, name) = match module_name.chars().next().unwrap() {
'&' => (
ModuleType::Conjunction(HashMap::new()),
module_name.chars().skip(1).collect(),
),
'%' => (
ModuleType::FlipFlop(false),
module_name.chars().skip(1).collect(),
),
_ => {
if module_name == "broadcaster" {
(ModuleType::Broadcast, module_name.to_string())
} else {
bail!("failed to parse module {module_name}")
}
}
};
Ok(Self {
name,
ty,
destinations,
low_pulses: 0,
high_pulses: 0,
})
}
}
pub struct Network {
modules: HashMap<String, Module>,
}
impl Network {
fn pulse(&mut self) {
let mut pulses = VecDeque::new();
pulses.push_front(("".to_string(), "broadcaster".to_string(), false));
while let Some((src, dest, high)) = pulses.pop_back() {
let module = self.modules.get_mut(&dest).unwrap();
if high {
module.high_pulses += 1;
} else {
module.low_pulses += 1;
}
let mut pulse = None;
match module.ty {
ModuleType::Broadcast => {
pulse = Some(high);
}
ModuleType::FlipFlop(ref mut on) => {
if !high {
*on = !*on;
pulse = Some(*on);
}
}
ModuleType::Conjunction(ref mut inputs) => {
*inputs.get_mut(&src).unwrap() = high;
pulse = Some(!inputs.values().all(|high| *high));
}
}
if let Some(pulse) = pulse {
for new_dest in module.destinations.clone() {
pulses.push_back((dest.to_string(), new_dest, pulse));
}
}
}
}
}
impl std::str::FromStr for Network {
type Err = anyhow::Error;
fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
let mut modules: HashMap<_, _> = s
.trim()
.split('\n')
.map(|s| {
let module: Module = s.parse()?;
Ok::<_, Self::Err>((module.name.clone(), module))
})
.collect::<Result<_, _>>()?;
let module_names: Vec<_> = modules.keys().cloned().collect();
for name in module_names {
let destinations = modules[&name].destinations.clone();
for dest in destinations {
if let Some(ModuleType::Conjunction(ref mut inputs)) =
modules.get_mut(&dest).map(|module| &mut module.ty)
{
inputs.insert(name.clone(), false);
}
}
}
let destinations: HashSet<String> = modules
.values()
.flat_map(|module| module.destinations.iter())
.cloned()
.collect();
for destination in destinations {
if !modules.contains_key(&destination) {
modules.insert(
destination.clone(),
Module {
name: destination,
ty: ModuleType::Broadcast,
destinations: vec![],
low_pulses: 0,
high_pulses: 0,
},
);
}
}
Ok(Self { modules })
}
}
pub fn parse(mut fh: File) -> Result<Network> {
let mut s = String::new();
fh.read_to_string(&mut s)?;
s.parse()
}
pub fn part1(mut network: Network) -> Result<i64> {
for _ in 0..1000 {
network.pulse();
}
Ok(network
.modules
.values()
.map(|module| module.low_pulses)
.sum::<i64>()
* network
.modules
.values()
.map(|module| module.high_pulses)
.sum::<i64>())
}
pub fn part2(_: Network) -> Result<i64> {
// let mut count = 0;
// loop {
// network.pulse();
// count += 1;
// if network.modules.get("rx").unwrap().low_pulses > 0 {
// return Ok(count);
// }
// }
todo!()
}
#[test]
fn test() {
assert_eq!(
part1(parse(parse::data(2023, 20).unwrap()).unwrap()).unwrap(),
681194780
);
assert_eq!(
part2(parse(parse::data(2023, 20).unwrap()).unwrap()).unwrap(),
0
);
}
|
