AdventOfCode

  • Advent of Code 2025

    Advent of Code 2025

    Advent of Code is a global annual coding event, open to anybody. Juha-Matti Santala has written a beautiful description of what all this about. This saves me the effort of doing so myself. Thank you Juhis! In this blog, I am going to share my solutions and my thoughts about them. You may follow it…

  • Day 9: Movie Theatre

    Day 9: Movie Theatre

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. This one was a bitch! Actually: not so much, if I had read the puzzle properly. More about that further below. Part 1 was dead…

  • Day 8: Playground

    Day 8: Playground

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge We have a list of points x₁, x₂, … , xₙ in 3-dimensional space and order them in pairs P₁, P₂, … by…

  • Day 7: Laboratories

    Day 7: Laboratories

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge As often, we have a field. On the top, we have a beam pointing downwards. Whenever a beam hits a splitter, marked by…

  • Day 6: Trash Compactor

    Day 6: Trash Compactor

    I found part 2 of this puzzle rather fiddly. Difficulty is definitely increasing, bit by bit. Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge Input was this time a list of…

  • Day 5: Cafeteria

    Day 5: Cafeteria

    This was a fun puzzle, easy and yet rather life like. Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge Today, we were given two lists, one of possibly overlapping intervals, in…

  • Day 4: Printing Department

    Day 4: Printing Department

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge We have a quadratic field filled with the symbols . and @. Our task is to find the number of @ symbols with…

  • Day 3: Lobby

    Day 3: Lobby

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge Today we were given a list of integer numbers, like 19874, 20001, 89089, … The task was to pick out two digits of…

  • Day 2: Gift Shop

    Day 2: Gift Shop

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge We were given a comma separated list of number pairs, the pairs being separated by dashes, like 1000-1020. These were to be read…

  • Day 1: Secret Entrance

    Day 1: Secret Entrance

    Note: If you’re attempting to read this as a Fediverse post, you might find it rather confusing. I recommend using a web browser to read it properly, following this link. The challenge On day 1, we have to open a closed door with a rotary dial and a keypad. The dial has 100 positions from…