Add Exercise Matrix

[jpal91]

Per forum post - Adding Matrix to the Rust Track

Here's what I did:

• Added Matrix exercise from problem-specifications using rust-tooling/generate
• Created example.rs
• Added all required tests
• Created boilerplate in lib.rs

This is my first contribution so there's a chance I probably forgot something but it looks like all cargo and CI tests are running on my end, so hopefully we should be good.

Also, I increased the difficulty to 4 as depending on the implementation you could be working with nested iterators/map/collect, but I was going back and forth on this. If you think 1 is still more appropriate, just let me know and I'll switch it back.

Thanks!

[github-actions]

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[senekor]

Haven't done a detailed review yet, but it looks like you're not using the Tera template to generate the tests. Please do that so we can keep the test suite up-to-date easily. Fastest way to regenerate tests from the template: just update-exercise --slug word-count (need just installed)

You can find some tips about writing the Tera template in CONTRIBUTING.md.

[senekor]

I'd say difficulty 4 is fine. Looking through the config file, there are many other exercises at difficulty 4 which I would categorize as "light data structure handling".

[jpal91]

Sorry about that. I realized when I forked the repo the problem-specifications submodule didn't pull in correctly so the tests never wrote when I ran the generate command the first time. I thought I had to write all the tests from scratch 😆.

I think I got the hang of it and everything should be correct now.

[jpal91]

Sorry about that. I realized when I forked the repo the problem-specifications submodule didn't pull in correctly so the tests never wrote when I ran the generate command the first time. I thought I had to write all the tests from scratch 😆.

I think I got the hang of it and everything should be correct now.

[senekor]

Great work! Just one more request, then I'll merge.

I think it's important to stick to problem-specifications as closely as reasonable and document justified deviations verbosely.

[senekor]

Thank you for the great work!