bwc9876.dev
Advent of Code solutions
Day 11: Some cleanup
+13
-16
years/2025/src/day_11.rs
+13
-16
years/2025/src/day_11.rs
···
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5
pub struct Day11;
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type Graph = HashMap<String, Vec<String>>;
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-
type Seen<'a> = HashMap<(&'a String, bool, bool), usize>;
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+
type Seen<'a> = HashMap<&'a String, usize>;
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+
type SeenConstrained<'a> = HashMap<(&'a String, bool, bool), usize>;
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-
fn all_paths_to_out<'a>(
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-
node: &'a String,
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-
graph: &'a Graph,
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-
seen: &mut HashMap<&'a String, usize>,
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-
) -> usize {
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+
fn all_paths_to_out<'a>(node: &'a String, graph: &'a Graph, seen: &mut Seen<'a>) -> usize {
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if let Some(memo) = seen.get(&node) {
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*memo
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} else if let Some(nexts) = graph.get(node) {
···
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}
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}
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-
fn all_paths_to_out_with_constraints<'a>(
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+
fn all_paths_to_out_constrained<'a>(
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node: &'a String,
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saw_dac: bool,
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saw_fft: bool,
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graph: &'a Graph,
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-
seen: &mut Seen<'a>,
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+
seen: &mut SeenConstrained<'a>,
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) -> usize {
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if let Some(memo) = seen.get(&(node, saw_dac, saw_fft)) {
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*memo
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} else if let Some(nexts) = graph.get(node) {
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let mut amnt = 0;
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for next in nexts.iter() {
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-
if next == "out" && saw_fft && saw_dac {
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-
amnt += 1;
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+
if next == "out" {
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+
if saw_dac && saw_fft {
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+
amnt += 1;
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+
}
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} else {
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-
let is_dac = next == "dac";
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-
let is_fft = next == "fft";
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-
amnt += all_paths_to_out_with_constraints(
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+
amnt += all_paths_to_out_constrained(
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next,
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-
saw_dac || is_dac,
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-
saw_fft || is_fft,
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+
saw_dac || next == "dac",
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+
saw_fft || next == "fft",
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graph,
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seen,
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);
···
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fn part_2(input: Self::Input) -> Option<String> {
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let mut seen = HashMap::with_capacity(input.len());
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let start = "svr".to_string();
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-
let ans = all_paths_to_out_with_constraints(&start, false, false, &input, &mut seen);
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+
let ans = all_paths_to_out_constrained(&start, false, false, &input, &mut seen);
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Some(ans.to_string())
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}
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