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that seems more like a 1x0 matrix
Ruby 3.0 should be enabled, read this to learn how to do it
Please organize the structure of test fixture as following (although it has been mentioned in the attached link, I'm repeated here again)
describe "<This message should describe the categories of test groups inside this block>" do
it "<A short message describing this test group>" do
expect(...).to eq(...) #Assertions
#Or Test.assert_equals(user_response, reference_response)
Ruby 3.0 should be enabled, see this to learn how to do it
Yeah, there was a little typo (had * instead of +). Thanks for letting me know
Random tests sometimes generate  as input. Is this expected? Shouldn't it be put in fixed tests instead?
How this is different from lot of others make spiral kata?
Alright. All three methods pass in less than 3s now, much more reasonable. Thanks for considering my (admittedly ranty) feedback.
Ok, fixed.Can you make the downvote go away? :D
I agree, this should definitely be a 4kyu