I loved day 19 because I managed to use some Automata theory I studied at uni. Something like, I cannot simply use a regex because it's a context-free grammar.

I loved day 19 because I managed to use some Automata theory I studied at uni. Something like, I cannot simply use a regex because it's a context-free grammar. Then I learned about recursive regexes and how they could be used to parse a cfg. Aaah fascinating, really.