I’m using sqlite this year. Hoping that there won’t be any computational geometry or trie problems. Kind of hoping for a graph problem solvable with recursive CTEs, that would be cool.
I've been doing a lot with SQL for the first time in my life, this is tempting. I posted some SQLite CTE dark magic the other day but I certainly didn't understand it.
Edit: Someone else posted an "Advent of " list which included https://adventofsql.com/, perhaps those problems will be a little more pedestrian for SQL.
Update: Wow. Reading your solutions was a real eye-opener for me. It never struck me that one can exploit the fact that unmaterialized CTE's will not be evaluated for rows that is not needed by another SELECT and one can use this the same way one uses laziness in Haskell. This is great stuff, thanks again for sharing!
I've solved some days in past years with sqlite + enough awk to transform the input into something that can be imported into a table. It can be a fun challenge.
