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import adglent.{First, Second}
import gleam/io
import gleam/dict.{type Dict}
import gleam/queue.{type Queue}
import gleam/string
import gleam/list
import gleam/bool
type Node {
Broadcaster(children: List(String))
Flipflop(children: List(String), state: Power)
Conjunction(children: List(String), state: Dict(String, TonePitch))
Ground(children: List(String))
}
type Tone {
Tone(from: String, to: String, pitch: TonePitch)
}
type Power {
On
Off
}
type TonePitch {
Low
High
}
fn flip_power(p: Power) -> Power {
case p {
On -> Off
Off -> On
}
}
fn flip_flop_pitch(p: Power) -> TonePitch {
case p {
Off -> High
On -> Low
}
}
fn parse_node(input: String) -> #(String, Node) {
let assert [full_name, children_str] = string.split(input, on: " -> ")
let children = string.split(children_str, on: ", ")
case full_name {
"%" <> name -> #(name, Flipflop(children: children, state: Off))
"&" <> name -> #(name, Conjunction(children: children, state: dict.new()))
"broadcaster" -> #("broadcaster", Broadcaster(children: children))
name -> #(name, Ground([]))
}
}
fn to_initial_state(nodes: List(#(String, Node))) -> Dict(String, Node) {
let node_dict = dict.from_list(nodes)
let node_names = dict.keys(node_dict)
use name, node <- dict.map_values(node_dict)
case node {
Conjunction(state: _, children: chs) ->
node_names
|> list.filter(fn(n) {
let assert Ok(node) = dict.get(node_dict, n)
list.contains(node.children, any: name)
})
|> list.map(fn(n) { #(n, Low) })
|> dict.from_list()
|> fn(dict) { Conjunction(state: dict, children: chs) }
other -> other
}
}
fn press_button_once(
initial: #(Dict(String, Node), Int, Int),
queue: Queue(Tone),
) {
let #(nodes, high, low) = initial
use <- bool.guard(queue.is_empty(queue), initial)
let assert Ok(#(Tone(from_name, to_name, pitch) as tone, rest)) =
queue.pop_front(queue)
io.debug(tone)
let assert Ok(to_node) = dict.get(nodes, to_name)
case to_node {
Broadcaster(children) ->
list.fold(children, rest, fn(acc, c) {
queue.push_back(acc, Tone(from: to_name, to: c, pitch: pitch))
})
|> press_button_once(initial, _)
Conjunction(state: state, children: children) -> todo
Flipflop(..) if pitch == High -> press_button_once(initial, rest)
Flipflop(state: state, children: children) -> {
let updated_nodes =
dict.insert(
nodes,
to_name,
Flipflop(state: flip_power(state), children: children),
)
let updated_queue =
list.fold(children, rest, fn(acc, c) {
queue.push_back(
acc,
Tone(from: to_name, to: c, pitch: flip_flop_pitch(state)),
)
})
press_button_once(#(updated_nodes, 0, 0), updated_queue)
}
Ground(..) -> press_button_once(initial, rest)
}
}
pub fn part1(input: String) {
let initial_state =
input
|> string.split(on: "\n")
|> list.map(parse_node)
|> to_initial_state()
press_button_once(
#(initial_state, 0, 1),
[Tone("button", "broadcaster", Low)]
|> queue.from_list,
)
"1"
}
pub fn part2(input: String) {
todo as "Implement solution to part 2"
}
pub fn main() {
let assert Ok(part) = adglent.get_part()
let assert Ok(input) = adglent.get_input("20")
case part {
First ->
part1(input)
|> adglent.inspect
|> io.println
Second ->
part2(input)
|> adglent.inspect
|> io.println
}
}
|
