What can I say? A problem that demands recursive manipulation of a giant list. Could a LISP ask for a more suitable job? No.
Didn’t take me too long. But like others I found that my first-crack solutions for both parts failed to get the correct answer for the actual input, despite getting the correct answer for the supplied example inputs. Turns out the supplied examples don’t cover all the edge-cases encountered in the actual input (like zero-element children).
Here it is! day08.rkt
I’m still catching up! Off to day 9!