Advent of Code

Part of the series Advent of Code (1 posts total).

• Aug 26, 2022 - Advent of Code

Advent of Code is an annual programming challenge with thousands of participants. From the 1st to the 25th of December a programming challenge is released with a cute accompanying christmas story and a goal. Every challenge boils down to taking some input in the form of a text file, parsing it, and computing a number for the first part and the second part of the challenge. These numbers are then input to the website, which tells you if you got the right answer.

Each challenge has an example input and a corresponding result for that exact input. Developers can use this example to test their implementation before trying with their own input. This input is generated by Advent of Code and is unique to each developer. This also means that each answer is unique - your answer to Advent of Code 2025 Day 1 part 1 is not the same as mine!

I have taken part in multiple of these over the years. There is a leaderboard for speed, but I don’t compete. I typically just go through them leisurely at another point in time. In fact, many of my challenges are completed in summer. Advent calendars in the summer…

These are the years I did:

• 2018: Completed 70% of challenges in Python. The code is available at joulsen/Advent-of-Code-2k18
• 2020: Completed 80% of challenges in Python. The code is available at joulsen/Advent-of-Code-2k20
• 2024: In progress (leisurely) in C++. The code is available at joulsen/Advent-of-Code2k24

I made a graph showing the amount of answers for each part of each day from 2020. As you can see, it falls off quite a lot - some of the later challenges tend to get pretty difficult!