util.ts is the utility library. It is built into util.js, and has type declarations available in util.d.ts.

index.js runs each file in parallel. The list of files it runs are in times.json, which also includes the last time in milliseconds it took to run the test cases.

Do not use an individual day's test case as a standard for comparison unless it is in the times.json file.

The .check() function from util.ts ensures a result is correct. The answers are hardcoded to my inputs, and will likely fail on your inputs, as inputs may be different for each person.

My inputs are not saved here. Run load.js with the ILOWI_AOC_COOKIE environment variable set to session=... (your Cookie header as sent to your browser) to download all inputs. Inputs are downloaded asynchronously on Node.JS, synchronously in the browser, and are cached in both.