[marc_omorain]

Clojure works really well for AOC.

A lot of the problems involve manipulating sets and maps, which Clojure makes really straightforward.

[Barrin92]

I'll second Clojure not just for the data structures but also because of the high level functions the standard library ships with.

Things like `partition`, `cycle` or `repeat` have come in so handy when working with segments of lists or the Conway's Game-of-Life type puzzles.