CPFAQ: Codeforces in Wikipedia


I’m working on a project this year to build a competitive programming FAQ. This is one in a series of articles describing the research, writing, and tool creation process. To read the whole series, see my CPFAQ category page.

In defining FAQ-related concepts like question categories, I always check Wikipedia to see what it has to say on a topic. For competitive programming, Wikipedia coverage can be uneven, and some articles start with the dreaded Wikipedia warnings about questionable notability or excessive reliance on primary sources. But Wikipedia is a quick way to verify that, for example, HackerRank is written in camel case, but Topcoder isn’t. (There’s no way to tell from the Topcoder logo).

As I was browsing competitive programming topics, I noticed that Codeforces (also not written in camel case) had no Wikipedia article. I thought that was strange, considering that Codeforces is one of the best-known online judges. So I decided to see what was up.

The Deleted Codeforces Article

I’ve been reading Wikipedia since it came online in the early 2000s, and have even made a few edits over the years. But I haven’t spent a lot of time writing articles. So I found out a few things about the editing process during this Codeforces experiment. As a first step, I clicked on the Codeforces link in the Online judge article. The link was red, indicating that the article did not exist. Clicking the link opened up an edit page. But in addition to the standard help text for new articles, there was a red section with the message: “A page with this title has previously been moved or deleted.” Interesting. (You can see an example of the red box at the edit page for LeetCode, a topic that has also been deleted).

The Codeforces revision history showed that the page was deleted in January of this year. This event made news on the Codeforces site, and a Codeforces user even claimed to have caused it. (It’s not clear what he did to make it happen).

Wikipedia has several ways to delete an article. In this case, the process that was used is called proposed deletion (PROD). The proposed deletion process requires that an article be marked for deletion for at least seven days. If anyone objects during that time, the process stops. Otherwise, an admin can delete the article with no further notice.

Fortunately, if someone (like me) objects to a PROD-type deletion after the article has been deleted, they can use a process called requests for undeletion (REFUND). That process notifies an admin, who can undelete the article. And that’s what happened.

Notability and Verifiability

The reason the Codeforces topic was deleted is that someone felt that it didn’t “meet Wikipedia’s general notability guideline.” Notability is the concept that Wikipedia editors use to decide whether a topic gets its own Wikipedia article. There are many rules and guidelines about notability, but the main idea is that a topic is notable if reliable third-party sources have written about it in detail. Having references to reliable sources allows Wikipedia readers to verify what has been written about a topic, and not have to blindly trust the Wikipedia editors. Requiring that the sources come from third parties avoids the problem of conflict of interest, which could happen if information for the article was taken only from the subject of the article (like a company’s web page).

To find the right kind of sources, I did some web searching with the goal of evaluating every result. This is the same thing I did earlier this year for the “competitive programming” search term. It soon became clear that most of what is written about Codeforces comes from Codeforces itself and from Quora, which is not considered a reliable source because content is submitted by users and is not professionally fact-checked or edited. (Wikipedia isn’t considered a reliable source for Wikipedia either, for the same reason).

I did find a few third-party sources that definitely meet the Wikipedia criteria for reliability. Some examples:

I also found a couple more from less well-known publications:

And finally, I found a few references by university professors who use Codeforces in their courses. For example: 15-295: Competition Programming and Problem Solving, Fall 2016 from Daniel Sleator of Carnegie Mellon.

The problem: none of these sources are primarily about Codeforces itself. They’re about competitive programming, though they mention Codeforces as an example or recommendation. Someone might argue that this is what Wikipedia considers a “trivial mention” of a topic. We’ll see. Nevertheless, I extracted what information I could from these sources, and added a few sections to the Codeforces article, along with citations.

Improving the Article

The undeleted and updated Codeforces article is now available, and ready to be improved according to Wikipedia standards.