advent-of-code VS advent-of-code-2021

This was a pretty fun day! I'm very glad that I took the time to write a small utility module for handling multidimensional arrays in Erlang a few days ago: otherwise, trying to wrestle coördinates would have quickly become painful. This was also my first time writing DFS in Erlang; a queue-based tail-recursive approach ended up being much cleaner than a simple recursive approach that used lists:foldl/3 to pass the modified matrix between neighbours. Writing the algorithm both was was definitely a great learning experience though!

Solution on GitHub

Java (nothing special, simple implementation of the rules, I have only posted to fit for the rules here)

Java, the code is still a mess, but if you need some tips, it might help.

Java Using Dijsktra's alogorithm to find the cheapest path.

Java

Java if you are interested.

If you are using custom Coord objects, you could consider going in and making a map of coord to value. Saves a bunch of boundaries checks, as you can see in zebalu's solution (another comment in thread) https://github.com/zebalu/advent-of-code-2021/blob/master/src/main/java/io/github/zebalu/aoc2021/Day09.java

Java 17, could be shorter, but I find this more readable (Gauss has helped a lot.)

Java nothing special:

Java 17, if you are looking for one. (However, it is not really a Java community...) I was really lost in diagonals, and it is not an "elegant" or less then 100 bytes of code solution, but I hope it is readable, if you are lost...

Hi! Nothing special, I might refactor later (since it is very rushed together), but Java 17, if you are interested.