Does it matter? I wouldn’t even bother giving recursion exercises as you mostly will never use it, I would rather just ask the difference between tail recursion and the generic one.
My opinion is that these exercises are only useful for hiring fresh graduates, as there is no way to ascertain their skills otherwise, as for people with experience, just ask them about some tricky things like concurrency in their language, and if they know what they are talking about then you are good to go.
