Merge pull request #12 from hildjj/day3

Day 3

day3.peggy

@@ -0,0 +1,11 @@
+commands
+  = cmd:command* { return cmd.filter(d => d != null) }
+
+command
+  = "don't()" { return false }
+  / "do()" { return true }
+  / "mul(" @num "," @num ")"
+  / . { return null }
+
+num
+  = n:$[0-9]+ { return parseInt(n, 10) }

day3.ts

@@ -0,0 +1,26 @@
+import { type MainArgs, parseFile } from './lib/utils.ts';
+
+type Parsed = (boolean | number[])[];
+
+function part1(inp: Parsed): number {
+  return inp
+    .filter((i) => Array.isArray(i))
+    .reduce((t, [l, r]) => t + (l * r), 0);
+}
+
+function part2(inp: Parsed): number {
+  let on = true;
+  return inp.reduce((t, v) => {
+    if (typeof v === 'boolean') {
+      on = v;
+    } else if (on) {
+      t += v[0] * v[1];
+    }
+    return t;
+  }, 0);
+}
+
+export default async function main(args: MainArgs): Promise<[number, number]> {
+  const inp = await parseFile<Parsed>(args);
+  return [part1(inp), part2(inp)];
+}

test/day3.js

@@ -0,0 +1 @@
+export default [187194524, 127092535];