I forgot about the advent of code as well. They are fun (and challenging) puzzles for sure. Would be nice if they listed some global "rules" like that the solution should be found by using TSQL. I know the first part of the first puzzle is trivial to do using Excel and only mildly difficult for the second part. Would also be nice if we are supposed to use TSQL, if the input was formatted for TSQL.
But any way you solve them is fun. it is interesting to challenge yourself and pick a tool you wouldn't normally use to solve these sorts of problems and see if you can do it. Since the link was posted on SSC, my first thought was to handle these in SQL Server, but decided I'd try a different approach and go with excel. Going to tackle more of them on the weekend though and see if I can get all 50 gold stars by the time the thing ends!