Since the tags were made invisible, in some cases It has been unclear to me what tools I should use to solve a particular problem. This is obvious (or unnecessary) for most problems, though a grey area between computer science problems and strictly math problems has emerged. For example, when I saw this problem, my gut instinct was oh, of course, this is a computer science problem, though the thought still lingered in the back of my mind that the intended solution may use nothing more than pen and paper and it's just not immediately obvious to me. I don't know about the rest of the community, but I try strictly limit myself to the tools (that I believe) the creator intended to be used to solve the problem, like not using calculus for an algebra minimization problem and especially not using a computer for a number theory question.
In short, can we let users specify the category their problem belongs to? Thanks.