In this algorithms question, I asked how to solve an algorithms question from a book, which I later realised I completely misread. The question I asked still led to some interesting discussion, but I don't think that it is possible to solve. As per the question in the book, you are in fact meant to return a new array, and not modify the original one.
One of the commenters called Vince, gave an answer which with slight modification, would have been correct had I specified the question correctly. I incorporated this answer into my question as an example of an insufficient solution alongside my own one, which had difference complexity characteristics. The comments which I took Vince's answer from seem to have disappeared.
In light of my error, I am now wondering how to proceed. Should I rename the question and correct it, posting Vince's now correct solution, or should the question just be deleted?