That being said: this question really raises about all red-flags a question can raise (no motivation, language errors, close to basic material,...). And, this in addition with the simple 'solution'...I could very easily see me having closed this, too.
Note: in case more should share this point of view, it might be worth making an edit to the question to make it more visible again. I did not do this (yet), as I am the first vote-to-reopen, and so thought it might be too early.
]]>Admittedly, it's not an exemplary MO question: the OP gave no motivation or source, didn't explain what methods he tried, etc. But I have a hunch that the question was closed mostly because it was deemed trivial, and that it isn't actually. (I'd be happy to be proven wrong.) Anyway, my point is that if my hunch is right, then the question looks moderately challenging but plausibly doable, and perhaps with a little more motivation or background provided, it should be acceptable as an MO question.
(I worry at times that a lot of questions are summarily dismissed as too easy for MO, without taking the trouble to be sure.)
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