Agreed. If article explained would make actual sense what the to-do is.

Including a good article explaining the concept this kata is referecing would be best. This isn't asking anyone to practice problem solving it is just wanting someone to already know what you're talking about. Not useful in current form.

best

So basically, to solve this problem, we have to look up unicode characters? What is the main learning goal of this specific problem? To be aware and familiar with the behaviour of different characters in the unicode when using certain methods?

Just find any symbol in any language which matches to this criteria. For solving this task you can use methods chr() and ord() to find a symbol (think about how use it)

I can make a hint that this kata is quite understandable and obvious for natural language learners, there is at least one widespread European language where one letter changes to two others when uppercased.

So many garbage kata lately, what is going on?

The condition of the problem is not clear to me

what is this?

While this behaviour is indeed an artifact of the testing system, it is also so easily accidentally stumbled upon that I would still consider the kata to be broken. It is also very easily fixed by moving the describe and it block from preloaded to the the sample and full tests. ( Fork here which fixes it )

Not a kata issue. Closing.

Don't add additional letters or blank lines of code. You were warned that "the size of your solution is limited."

Closing.

Except C++!