My solutions to the 2020 Advent of Code puzzle series (https://www.adventofcode.com/2020).
As an added self-imposed restriction, I wrote all data structure implementations (vector, set, etc.) from scratch as I went along, rather than using any third-party libraries. Note that they are not feature-complete, and probably not bug-free, so I do not recommend using them in other projects!
All solutions are compiled with make, and run from the command line. They expect the puzzle input to be provided on standard in, e.g. cat input01.txt | ./day01.
If the solutions run too slowly for your liking, make fast is provided for compiling with compiler optimizations enabled and debug features (mostly ASSERTs) disabled.
make clean deletes all program binaries in the current directory.