Although the inputs given by Advent of Code are very small and any solution is fine, I tried to write asymptotically optimal solutions. There is a folder for each day, and in each folder, a brief description of the solution.
My favourites are (first is better):
- Day 2 (hashing ftw)
- Day 7 (priority queues)
- Day 8 (some recursion)
- Day 5,9 (just nice)