Solutions for the puzzles of Advent of Code 2021, written in Java.
To download your input files, save your session ID into a file called session.txt in the input folder and
execute input/download.sh. (See the script for more details on how to get the session ID.)
The general utilities and algorithms used in the solutions are also available in a separate repository: https://github.com/p-kovacs/java-puzzle-utils
Many thanks to Eric Wastl for Advent of Code.