refactor

shahata · Dec 20, 2023 · bb43878 · bb43878
1 parent 19a70ba
commit bb43878
Showing 1 changed file with 19 additions and 33 deletions.
diff --git a/src/2023/day20.js b/src/2023/day20.js
@@ -3,50 +3,36 @@ function parse(input) {
     let [part, links] = line.split(' -> ');
     let type = part[0];
     if (type !== 'b') part = part.slice(1);
-    links = links.split(', ');
-    return [part, { part, type, links }];
+    return [part, { part, type, links: links.split(', ') }];
   });
   parts = Object.fromEntries(parts);
   Object.values(parts).forEach(part => {
-    if (part.type === '%') part.state = 'low';
+    if (part.type === '%') part.state = { on: false };
     if (part.type === '&') {
-      const linked = Object.values(parts).filter(x =>
-        x.links.includes(part.part),
-      );
-      part.memory = Object.fromEntries(linked.map(x => [x.part, 'low']));
+      const m = Object.values(parts).filter(x => x.links.includes(part.part));
+      part.state = { memory: Object.fromEntries(m.map(x => [x.part, false])) };
     }
   });
   return parts;
 }
 
 function signal(parts, wait) {
-  const queue = [{ part: 'broadcaster', level: 'low', from: 'button' }];
+  const queue = [{ part: 'broadcaster', level: false, from: 'button' }];
   let count = { low: 0, high: 0 };
   while (queue.length > 0) {
-    const { part, level, from } = queue.shift();
-    count[level]++;
+    let { part, level, from } = queue.shift();
+    count[level ? 'high' : 'low']++;
 
     if (`${part},${level},${from}` === wait) throw new Error('wait');
-    if (!parts[part]) continue;
-    if (parts[part].type === 'b') {
-      parts[part].links.forEach(link => {
-        queue.push({ part: link, level, from: part });
-      });
-    }
-    if (parts[part].type === '%' && level === 'low') {
-      parts[part].state = parts[part].state === 'low' ? 'high' : 'low';
-      parts[part].links.forEach(link => {
-        queue.push({ part: link, level: parts[part].state, from: part });
-      });
-    }
-    if (parts[part].type === '&') {
-      parts[part].memory[from] = level;
-      const allHigh = Object.values(parts[part].memory).every(
-        x => x === 'high',
-      );
-      parts[part].links.forEach(link => {
-        queue.push({ part: link, level: allHigh ? 'low' : 'high', from: part });
-      });
+    if (parts[part]) {
+      const { type, links, state } = parts[part];
+      if (type === '%' && level) continue;
+      if (type === '%') level = state.on = !state.on;
+      if (type === '&') {
+        state.memory[from] = level;
+        level = !Object.values(state.memory).every(x => x);
+      }
+      links.forEach(link => queue.push({ part: link, level, from: part }));
     }
   }
   return count;
@@ -67,7 +53,7 @@ function wait(input, part, from) {
   const parts = parse(input);
   for (let i = 1; i < Infinity; i++) {
     try {
-      signal(parts, `${part},high,${from}`);
+      signal(parts, `${part},true,${from}`);
     } catch {
       return i;
     }
@@ -76,7 +62,7 @@ function wait(input, part, from) {
 
 export function part2(input) {
   const parts = parse(input);
-  const conj = Object.values(parts).find(x => x.links[0] === 'rx');
-  const loops = Object.keys(conj.memory).map(x => wait(input, conj.part, x));
+  const { part, state } = Object.values(parts).find(x => x.links[0] === 'rx');
+  const loops = Object.keys(state.memory).map(x => wait(input, part, x));
   return loops.reduce((acc, x) => acc * x, 1);
 }