This guy GrievousPiggy got his submission skipped in today's contest even before the system testing was over, although he did not resubmit a solution to E1 at any point. The code in question passes the tests just fine and gets AC when resubmitted.

Also, somehow out of his two problem B submissions, the second one got skipped instead of the first one (I thought it should be the other way around?). Could it have to do anything with locking?

How do submissions get skipped actually? I thought there were 2 main reasons for a submission to get skipped:

• Resubmission in a Codeforces (non-ICPC) style contest, only the last submission to pass pretests gets judged
• Failing to pass the plag check (but obviously plag checks are not done during the contest)

Am I missing anything? Can a contest author/coordinator/headquarters stuff pick any submission and change its status to skipped?

Some other sussy stuff that I have noticed (it could be me just being a schizo)

• The solution looks very similar to the code provided in the editorial
• The last contest GrievousPiggy participated in was set by the same author

Hopefully zltzlt or 244mhq could shed some light on the situation

Here are the pictures of both submissions for the lazy people. I didn't notice much difference other than 0- and 1-indexing, slightly different order of initializing values and one condition being inversed: if(!R[i + 1]) and just a if(a[i]) instead. Also in the editorial b[maxn] array is never used.

You guys are most likely aware that cheating has become quite popular nowadays, however it seems like there's no clear cut way to put an end to it. In this blog I'm going to propose at least one way to make an impact on cheating that hasn't been brought up before.

• Make it so bad that Mike will have to get involved. Make sure that every single participant of any contest is unrated or skipped. Share solutions with your grandma, your dog and the neighbor next door, ensure that nothing makes it past the plag check. Obvious downsides of this are the tremendous amounts of group effort, waste of authors' and coordinators' time, the codeforces servers that will never recover from this and skewed ratings for some random people who aren't going to be a part of this group effort.

• Making shorter rounds. Make rounds shorter, so people wouldn't have time to sell, leak or modify solutions to pass the plag check. This would require changes to current contest format, and also nobody likes speedforces rounds (unless you are the one in the top 50 with just 4 solved problems), so this change is unlikely, although this would be the easiest way to make life for cheaters harder.

• Separating ranks and leaderboards by region. This way I won't have to compete with Chinese kids that are still in elementary school and are already solving A-E in 30 minutes of time. People wouldn't complain anymore that contest times are awkward because they have to wake up at 3:00 AM to participate. Also we could have Codeforces World Tour Finals with top participants from every region. Downsides of this are even more efforts from Mike to make changes on an already working system, as well as some regions not being as popular, dying out and people flocking to one or two main regions (so we're back to square one, but with even more convoluted system).

I'm also looking forward to fresh and bold suggestions in the comment section below. Anything that hasn't been proposed or discussed before, and that includes:

• Real ID/phone number authentication
• Blocking access to codeforces from certain countries
• Organizing cheat patrols
• Purposefully leaking wrong solutions
• Screencasts with the video camera turned on

P.S. Anything said by me in this blog is satire (unless you agree with me, then it's real. but if you disagree it's just a joke)