# How to determine if a question is from a current Contest.

I had never really heard of online contest math question before coming to this site. However, now that I am answering question, I would like to avoid these questions (and flag them). How do you go about matching these questions to current contest? Is it basically just typing terms in from the question in a search engine and trying to find matches, or are there specific sites you look at, or something else?

Thanks.

• I don't check every question. My heuristic: if the question looks like a homework problem, but is too hard for homework, then I start searching if it's a contest problem. There are also certain dead giveaways (integral constants of the form $20XY$ appearing in the problem, where $X\in \{0,1\}$, for instance.) Jun 6 '15 at 20:34
• I don't think you really need to - I generally assume that contest problems will be spotted by people who were already familiar with the contest, and that they will hopefully leave a comment and flag. But if a question seems up to the standards of the site and there's nothing which makes me suspicious, I don't go looking. (In the rare case where I do get suspicious, I just copy and paste part of the question into Google) Jun 6 '15 at 20:57
• The contest questions that I often see are programming questions, those that look for an algorithm. Jun 7 '15 at 1:27
• Occasionally there is also some post on meta mentioning an ongoing contest, like this one. Also sometimes there is post on meta pointing out that some particular problem from a contest appeared here, like this one. Jun 8 '15 at 5:13
• If a question mentions test data or asks for the number to be expressed modulo $10^9+7$ or the like, it’s probably from a programming contest. (Of course it may be from one that has already closed, in which case it may be a perfectly reasonable and even interesting question.) Jun 10 '15 at 1:48