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Comment by going_ham | Hacker News Reader

This puzzle is so cool because it revolves around casual graphs in classical planning problem! One can use heuristics based search to come up with optimal solutions. I really like this innovative approach to the design.

However, one edge from house to tree wasn't clear at first because, I thought of it as logical or while it was about logical and. Other than that, pretty awesome work!!

Edit:: Scrolling down the comments someone seems to already implemented a graph search. That is pretty quick: https://news.ycombinator.com/item?id=32885309

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Yeah the edge with two conditions was a little confusing;

(1) and

(2) or

(3) At bone to go up, at flower to go down [or the converse?]

Was able to figure it out through experimentation, but the signage doesn't make it obvious.

some kind of visual gate or a schematic-toggle-switch kind of thing would help

Or just one label that says "Somebody on bone and flower."

This gives me the idea to make variations of this puzzle to play with my 5yo using pencil and paper. It would be a fun way to teach the difference between AND and OR.

Plus I'll get to see the puzzles he comes up with, once he realizes he can make his own!

I'd love to see the formulation for this problem written out in proper form that can be fed to a solver like MiniZinc or CPLEX or whatever type of solver can handle it.

It looks like Hakan K (has a super cool website where he solves all kinds of optimization problems for fun) was able to solve it using the Picat language in a very small amount of code with a solution (not sure if optimal):

http://hakank.org/picat/dogbunny_puzzle.pi

His website is a treasure trove for these kinds of problems and worth studying.

The solution is 26 steps and that should be the optimal solution.

Awesome! Thanks for popping up and clarifying.

For those of us that are not experts, how is this sort of problem generally classified? I've seen others on here say classical planning, but I wasn't sure if that is correct.

I would (also) say that this is a classic planning problem. It's deterministic, observable, static, and discrete.

I appreciate the clarification here. It helps. Thanks!

I didn't have a problem with that edge.

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