Advent of Code

This repository contains my own solutions to the Advent of Code coding puzzles.

Spoiler alert!

If you don't want those puzzles spoiled for you, don't look at the code!

Dependencies

It runs on Python 3.10+.

The puzzle-solving code is almost all purely Python Standard Library stuff. The only required external dependency is numpy.

Required dependencies

• numpy

Optional dependencies

There are also some optional dependencies to enable extra features:

• rich, for pretty printing on the console
• pillow, for rendering visualisations
• numba, to speed up some of the number-crunchy solutions
• pytest, to run the test suite

Installation

1. Clone the repo
2. Change into the top-level repo directory
3. Execute python3 -m venv .venv to create a Python virtual environment
4. Execute source .venv/bin/activate to activate the virtual environment
5. Execute pip install -r requirements.txt to install all required and optional Python package dependencies

Usage

To simply run the solution for a puzzle, execute advent.py at the top-level of the repository, with the year and day number as positional arguments, for example:

./advent.py 2023 9

You can give the -t/--test argument to run the test case from the puzzle explanation instead of the actual puzzle, -v/--verbose to enable debug logging, or -d/--draw to output a visualisation (if the puzzle code supports that).

You can also run ./advent.py without any arguments to enter an interactive mode which looks like this:

In the interactive mode, you can set up a new puzzle solution module from a template, add example inputs, download your actual inputs, toggle the visualisation and logging modes and run your solution in real or testing mode.

The interactive mode uses hot module loading, so in most cases you can re-run your solution after making changes without ever leaving interactive mode. The exceptions are when you make changes in another module that is imported by the solution, or you are changing functions that are under numba.jit compilation. In those cases you will need to exit and restart the interactive mode.

Visualisations

Here's a sample of some of the visualisations I generated for these puzzles, using my own custom animation rendering code, plus Pillow:

2015 Day 18, part 1 "Like a GIF For Your Yard"

2015 Day 22 "Wizard Simulator 20XX"

2016 Day 8 "Two-Factor Authentication"

2016 Day 13, part 1 "A Maze of Twisty Little Cubicles"

Using Breadth-first search (left) and A Star (right) to solve the maze.

2019 Day 15, "Oxygen System"

2024 Day 9, "Disk Fragmenter"

2024 Day 14, "Restroom Redoubt"

2024 Day 15, "Warehouse Woes"