Advent of Code in Node.js and Javascript

Helper utils and solutions for AoC

Setup

Install node and yarn then use yarn to install the required packages. Show the help message and try to run the first example 01/2015 and check the tests.

brew install node yarn
yarn install
yarn solve help
yarn solve 0 1 2015
yarn test
yarn all

Prepare automatic download

In order to run a real example with automatic input download follow these steps. Sign in from your browser and use the developer tools to retrieve your AoC session cookie. In Chrome open https://adventofcode.com/ an sign in, press "Ctrl-Shift-I" or "Command-Option-I" (Mac), select "network", reload the page, select the first entry and scroll down to the "Request Headers" section and find the value for "cookie". There you copy the string starting with "session=" until the next semicolon. Set this as environment variable AOC_COOKIE.

export AOC_COOKIE='session=34543c7465645f5fdf...4e436254bca92710;'
curl https://adventofcode.com/2015/day/1/input --cookie $AOC_COOKIE

You should receive a lengthy text of characters '(' and ')'. If this works you are set to start.

This fork's Alternative: using dotenv

Create a .env file at root's project. Fill it with your environment variable

AOC_COOKIE='session=34543c7465645f5fdf...4e436254bca92710;'

The solve util has been modified to use dotenv and retrieve the environment variable. For security, this .env file is ignored on .gitignore.

Run

Run the solver for any valid date. In case you are solving the puzzle on the same day you can omit the parameters and it will try to load from the current year and/or day. Also try the tests and check out the skeleton code.

yarn solve 0 1 2015
yarn test 2015/01
vi src/2015/01/puzzle.js

Submit Solution

If you are confident your code calculates the correct puzzle solution you can directly submit the answer. Here for example first part of Dec 1 in 2020

yarn solve 1 1 2020

Troubleshooting

In case you keep receiving the input

Puzzle inputs differ by user.  Please log in to get your puzzle input.

Make sure you have set the AOC session cookie like described above AND also remove that input from the day folder because the utils will only try to download when there is no input already present.

echo $AOC_COOKIE    
rm src/2015/01/input
yarn solve 0 1 2015

Visualizations

I visualized some of the examples and put them here https://rohrmeier.s3.eu-central-1.amazonaws.com/aoc/index.html If you want want to play with it, you can start a local webserver

yarn start