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Good luck
FYI one of the features of Advent of Code is that we all get given different inputs so our answers will be different.
The examples are all the same but each of us gets different inputs for us to solve
I found Part 1 the easiest puzzle so far this year
Part 2 will probably be MUCH harder
[edit] I have the correct answer to Part 2 but not quite worked out how to get it programmatically!
[edit2] I have code to produce the correct answer but I'm not sure why it works as I can't reconcile it to what Wikipedia says in the clue
I, too, found the answer to part 2. Itβs a huge number, impossible to calculate with brute force.
Fortunately, for each ??A start node, the period of repetition is exactly the same as the number of steps for reaching the first ??Z end node. The answer is the Least Common Multiple of all periods.