Spent some time to write my solving process for days 18, 19 and 23 for this year. You'll find the links to the full Nim solution too!
Day 18: <https://github.com/h-j-k/advent21/blob/master/walkthrough/day18.md> Day 19: <https://github.com/h-j-k/advent21/blob/master/walkthrough/day19.md> Day 23: <https://github.com/h-j-k/advent21/blob/master/walkthrough/day23.md>
