Cool, you are getting better and better. This time I was really close to understanding.
Pavel Rihosek

Take a pen and pencil and draw a few lists. It helped me, too, since it empowers intuition behind. I only had to come up with the equations to prove the algorithm really worked.

To implement the cycle detection, I had to

  1. draw about 10 different lists on the paper
  2. implement the algorithm
  3. come up with equations to prove the idea and find bug
  4. get back to step #1

Drawing definitely helps most.

Regarding to the second part, no, I don’t think I would be abusing syntax.

If you run the notebook to play and debug the algorithm, you may find useful to keep more information on the node, too.

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