A record of my solutions for 2023 Advent Of Code.

I have not attended AoC in 2023. I have now (2025) decided to practice and relearn C++. It has been around six years since I last touched any C language.

Solutions for each day and task are in separate files.

To run the solution:

1. Build the designated solution file along with ../runner.cpp and ../utils.cpp. (Consult the .vscode folder in case of troubles.)
2. Default build and run task uses test parameter. It uses the puzzle input, when running executable without any parameter. The puzzle input file should be named the same as the test input, but without _test suffix.
3. Alternatively, you can run the solution with a custom test input file changing the main function accordingly (test_run() -> run(path)).

Data for each task can be accessed through the site.

All solutions but two run under a second on my machine. Day 23 part 2 completes in under 4 seconds, and Day 25 uses a custom heuristic, which may or may not be fast enough. I opted for a heuristic because I did not want to copy code from Wikipedia — which in non-challenge scenario would be the sane thing to do.

50/50⭐

	日	月	火	水	木	金	土
Week 1	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐
Week 2	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐
Week 3	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ ⭐
Week 4	⭐ ⭐	⭐ ⭐	⭐ ⭐	⭐ 🌟	🎄  🎄

An estimated rundown of the time invested in each day puzzle (includes coding and coding-adjacent activities). Bar sections represent from the leftmost: first part solution, second part solution, solutions refinement and utilities.

Day  1 | ███████████████|████████████| 225
Day  2 | ████████|███████|██████ 174
Day  3 | ██████|█████|█████████ 165
Day  4 | ██████|█████| 91
Day  5 | ██████████████|█████████████████|████████ 320
Day  6 | ████|████|██ 86
Day  7 | ████████████|██| 116
Day  8 | █████████|███████████████████████████| 299
Day  9 | █████|█|█ 58
Day 10 | ███████████|████████|█████████ 232
Day 11 | ███|██|████ 72
Day 12 | ██████████|███|█████████ 185
Day 13 | ███████████|████| 121
Day 14 | █████|██████████|█ 135
Day 15 | ████|██████| 82
Day 16 | ████████|████| 102
Day 17 | ███████████|█|██████████████████████████████████ 385
Day 18 | ██████████████████████████████████|█|███ 317
Day 19 | ███████|██████████| 140
Day 20 | ███████████████████|████████████████████████████████| 427
Day 21 | █████|██████████████████████████████████████████████████████████|██ 539
Day 22 | ████████████████████████|█████████| 277
Day 23 | ████████|████████|████████████████ 265
Day 24 | █████████████|████████████████████| 272
Day 25 | ███████████████████████████████████████||███ 347