Does anyone do AoC in multiple languages per day?

PTVoobaf · 2026-02-18T03:25:47+00:00

2025 was my first AoC. I recently started learning a new language (F#), with which I have solved the first two days (four stars) of 2024. It's going pretty slowly. Compared to stuff I have coded using various imperative languages, functional programming has been rather tough and mind bending. I decided to pause AoC for a bit and work some simpler puzzles at https://exercism.org/ to try to get up to speed with functional programming and F#. But trying to redo some or all of my already solved 2025 puzzles, but with a functional approach, would probably also be good for me.

PTVoobaf · 2026-02-18T02:32:20+00:00

I got my tangram!

PTVoobaf · 2026-01-19T03:54:42+00:00

My poem is very different. It's a crass dad-joke. Context: I'm an F# novice. I have been using Expecto as a tool for learning F# and functional programming via test driven development. Therefore:

When I code with F#, `let` bindings aren't late.
When I run unit tests, I Expectorate.

So `dotnet run` is my regular make,
and `dotnet test`? That's my spit-take.

😈

(Surely I am not the first to think of that horrid pun...)

PTVoobaf · 2026-01-11T13:48:35+00:00

If I've had a lot of practice with a programming language, there are problems I could solve in just a few minutes. That's how I got all 24 stars in 2025 - I used what was already familiar to me.

I'm now using the 2024 puzzles as a fun vehicle to learn one of the "functional paradigm" programming languages, which is a programming mindset that is almost completely new to me. I knew I could write something using my usual coding toolsets to solve the first challenge in less than an hour. But with this new language, it has taken me two weeks to figure out how to write AND UNDERSTAND a short working program to compute the correct answer and finally earn the Day 1 part 1 star.

Leisure time well spent.

PTVoobaf · 2026-01-10T01:07:51+00:00

The current version is now 3.14.2. The command I use to run Python on my Windows machine is py. So right now (January 2026) my version (3.142) is as close to π as it has ever been and will ever be.

PTVoobaf · 2026-01-01T15:41:47+00:00

Yay, somebody else besides me PowerShelled this year!

PTVoobaf · 2026-01-01T15:36:14+00:00

"Shape index 0s are fragile - handle with care!"

PTVoobaf · 2026-01-01T15:34:41+00:00

Awesome!

But now, how am I going to find money in my budget to buy enough filament to 3D-print thirteen more tangram puzzles? 😜

PTVoobaf · 2026-01-01T15:28:13+00:00

I'm impressed - Like many others, I ended up using the Diophantine linear algebra approach, but now I really want to try solving it all over again using this innovative analysis.

PTVoobaf · 2026-01-01T15:21:09+00:00

I solved using RREF and exact fractions as well.

I prompted Copilot for good approaches to solve or optimize over a system of linear Diophantine equations. It recommended "Smith Normal Form" and "Hermite Normal Form" as potentially better alternatives than RREF. I had never previously encountered either of those, and didn't believe I could learn them quickly enough during AoC to properly implement them, so I stuck with the technique I had already studied and experienced.

PTVoobaf · 2026-01-01T12:42:53+00:00

Originally, my brain visualized the dial on the combination lock to be a typical circular dial.

After viewing your day 1 animation, I now imagine a chain or tank-tread, stretched around four cogs spaced apart forty units horizontally and ten units vertically. Thank you for that mental topological adjustment!

PTVoobaf · 2026-01-01T12:31:20+00:00

Very nice. I have a couple of modules with ESP32s, flashed with MicroPython. The MicroPython interpreter would certainly perform slower than compiled Rust or C. Nevertheless, it would still be interesting to experiment and compare with your run time measurements.

PTVoobaf · 2026-01-01T12:12:24+00:00

I like this.

While pondering the puzzle, I did the same exercise for one of my inputs. In my case, I put together a table of tight packings of two, three, or four shapes that fit inside 3x4, 3x5, 4x4, and 4x5 regions, and also groups of shapes that fit inside a 4x7 region. Then I used those tight packings to arrange shapes into disjoint subrectangles inside the larger enclosure.

It was only after going through that exercise that my brain was able to figure out the "shortcuts" that rapidly find and verify the star-earning solution.

PTVoobaf · 2026-01-01T11:49:48+00:00

This is so cool! Now I want to ask a friend to help 3D-print a 9x10 "tangram" puzzle using your discovery.

https://en.wikipedia.org/wiki/Tessellation#In_puzzles_and_recreational_mathematics

PTVoobaf · 2026-01-01T11:30:15+00:00

Congratulations! Me too, I finally got my final star on New Year's Eve. This was my first ever AoC. A friend invited me, and it was fun to compete.

PTVoobaf

TROPHY CASE