I am absolutely disgusted by the fact that most of the problems on this site are from the math website AoPS (Art Of Problem Solving). From the badly formatted LaTeX and the leftover Asymptote code, not to mention the identical text, it is absolutely clear that the users posting these questions are cheaters. The AoPS Website specifically states in its honor code that when a problem gets too difficult, then the student should ask about it on the CLASS MESSAGE BOARD, instead of elsewhere, to prevent cheating.
So is there any measure we can set up to prevent this?
I try not to answer AOPS problems.....if I'm aware that they ARE AOPS problems
It's disgusting how people cheat.
I've seen way too many questions of competitions that I've done and are still running (there's usually a time frame for it to be completed).
I try to avoid answering any questions when I know a competition I'm doing is happening since it'd be cheating if I had seen/solved the questions beforehand.
However, I doubt there's any real method to prevent cheating other than reporting the person, and quite simply, the chance of someone recongnizing a question used for cheating before someone else answers it is quite low.
Perhaps CPhill, Melody, Alan, Asinus, or any other moderator could contact websites like AOPS, AMC, or MathCounts to get a database of questions that are on tests that they can ban. But that'd be kinda hard to do.
The problems from AoPS Mainly come from special classes, where the problems are not allowed to be shared. I don't think there is another way to access other problems either...
Probably the only thing we can actually do is to just watch out for problems during competition times.