Here are my attempts at the Advent of Code 2021 challenges, all using Kotlin.
Each day's answers can be found in the src/main/kotlin/ directory, with one Kotlin File/Class per day.
I have attempted to use the power of idiomatic Kotlin where possible, but I am sure many of these puzzles can be solved in more elegant and idiomatic ways. I have also tried to favour functional and immutability where possible.