Hmmm #AdventOfCode day 12 was path finding (called hill climbing) and day 12+12 (aka 24) is path finding (called avoiding blizzards). Is that a coincidence, or is Eric out of interesting ways to make challenges?
@Lownewulf @PHolder Agreed. Also, Topaz does this most years - there'll be a strong theme... A couple years ago almost every-other-challenge after day 9 had us improve upon this programming language interpreter/microprocessor simulator thing.
This has been the year of "search" for me, or even breadth-first search mostly.