smart

On one hand it's the temptation and ease of regex, on the other is the temptation of writing a beautifully structured interpreter toolchain

Well done!
I'm not a big fan of regex, but this demonstrates it can help to concentrate on the essential stuff, leaving all the tokenization on a single line.

Thanks, there are 31 random tests of each category.

Hi, Nice Kata. How many larger random tests there are?

Thanks for the hours of fun with this series!!!

A lot of fun from this kata. Most of time is consumed researching the math to create routes and measure distance. Visualizer from Blind4Basics is very useful for debug, took it as a base and added code to display my solution, routes, discarded routes. That help me to locate my error.

late answer, but.... no, it's not the good way to solve this.

too many useless iteration steps, rather decide for optimization and efficiency instead of better appearance or cruelty.

Very nice kata, thank you guys.

Nice Kata!!

I just thought this sentence could be reformulated a bit: "It must be possible to follow the line with no ambiguity (lookahead of just one step, and never treading on the same spot twice)."

We misinterpreted it like, if you have two options to go from a corner, but only one leads to a valid path, then the line would still be valid.

I'm no native speaker, but what about something like: "It must be possible to follow the line without ever treading on the same spot twice, and by going step by step without ever having to choose between two adjacent and still unvisited tiles to go next. (The latter condition might hold only in one direction. The line will still be considered valid in this case.)"

The Kata description is not clear.

I think there is no problem with the description except too many people do not read it carefully.

How is it not clear? How should it be improved?

I wonder if it is the same i am failing, i do not understand why it is not valid.

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