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 created a repo for my solutions here: https://github.com/lyxell/aoc2024-sqlite
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!