Advent of code 2025

This is my repository for the Advent of Code 2024. I will be solving the puzzles in Dosato.

Context

Dosato is a programming language that I created. It is a unique and robust intepreted language designed for the general purpose. It is a high-level language that is easy to learn and use. This is one of the main reasons why I chose to use Dosato for solving the Advent of Code puzzles.

Why Dosato?

I like it :P, it's really not a bad language for this and I barely get any extra challenges from the language itself. It is also just cool to solve these puzzles in a language that I created myself.

How to run the code

To run the code, you will need to have the Dosato interpreter installed on your machine. You can download the Dosato interpreter here. Once you have the Dosato interpreter installed, you can run the code by typing the following command in the terminal:

dosato <filename>

Where <filename> is the name of the Dosato file that you want to run. For example, if you want to run the code in the file day1.to, you would type the following command in the terminal:

dosato day1.to

Thats it really. I hope you enjoy the solutions. Feel free to reach out to me if you have any questions or suggestions. I am always happy to help.

Log

Day 1

• Part 1
  • Ended up doing the mathy approach
• Part 2
  • Mathy approach was not the easier way here, spending more time than I wanted to on this one, but switched to a more straightforward approach and got it done. Optimised to use a mathy approach after the fact.

Day 2

• Part 1
  • Straightforward implementation, but a bit slow.
• Part 2
  • This slowness carried over to part 2 as well. Need to optimise this heavily, there must be some trick to detect repeated digits without checking the ENTIRE range. (update later: I made it way quicker with modulos)

Day 3

• Part 1
  • Very easy implementation.
• Part 2
  • Had to remake the entire thing to accomodate for the new logic, but it was still pretty straightforward, works with any battery size.

Day 4

• Part 1
  • Initial implementation, straightforward.
• Part 2
  • Fun solve, but was a bit slow, so I improved it by using a stack to keep track of what needs to be checked, instead of checking the entire grid every iteration.

Day 5

• Part 1
  • My brain decided to not wake up on time today, so I was late, part 1 was easy though.
• Part 2
  • I was overthinking this one too much, in this end sorting the start and end positions and keeping track of how many ranges cover each position, works really quickly.

Day 6

• Part 1
  • I woke at at 9am to preserve my sanity, anyways, very easy day.
• Part 2
  • Same as part 1, I merged them all into collumns and just did it, very easy day today.

Day 7

• Part 1
  • Solution ended up being pretty straightforward, just simulating the process.
• Part 2
  • Instead of a recursive solution, just keep track of the amount of timelines per row, and add accordingly, ended up being pretty quick.

Day 8

• Part 1
  • Initially tried to do a more complex solution, then also realised I read the instructions wrong. After that and a very painful bug on my end, I got it done.
• Part 2
  • had to rewrite it completely, and managed to update part 1 to use the same logic. Ended up being a pretty fun solve.

Day 9

• Part 1
  • Straightforward implementation of the problem statement.
• Part 2
  • Way harder, In the end grouped all edges together, and ran for each rect combination. It's kinda bruteforcey but it works.

Day 10

• Part 1
  • Very clean and elegant solution by XORing all combinations of buttons until the correct light configuration is found.
• Part 2
  • Unfortunetely couldn't think of a programmatic way to solve part 2, so I caved in and used python with z3 to solve it really quickly. A bit of a bummer, might get back to it later.

Day 11

• Part 1
  • Memoized DFS to count all paths from "you" to "out".
• Part 2
  • Reused the memoized DFS to count all paths for the segments and multiplied the results. Decided to remove the cache as it was tainted per call, so I passed it as a parameter.

Day 12

• Part 1
  • I originally overcomplicated this one a lot, but because of my sanity check, it seemed like theres so much room left over, so I could just count the areas and check if they fit.
• Part 2
  • Merry Christmas!