This blog is about Corruption and Cheating at ICPC YinchuanRegional. ICPC Yinchuan Regional is one of the ICPC regional contests for students competing in the geographic area of Asia East Continent.

I. Background: General Info

Ningxia Institute of Science of Technology, or NXIST is a higher education institute in China. Since 2019, NXIST has held two regional contests. The and both were considered by many participants as jokes, yet until today participants are unaware of the NXIST's extent of evil.

Zhihu is a Chinese website similar to Quora, and I will refer to this website for information.

II. Background: Before 2021

Regional competitions in China consists of two stages: The online selection contest and the onsite regional contest. As there are many contestants in China, the online contest is considered serious and rules are usually strictly enforced, with entire universities where some participant cheats disqualified from attending the onsite regional.

In 2018, NXIST claimed that whoever attends their invitational competition can attend regional contests directly, leading to angry discussions https://www.zhihu.com/question/276204455.

The original information sent to the participants is as follows:

English translation via Google Translate:

Each participating university:
The receipt you sent has been received. In order to encourage more schools and college students to participate in the ACM ICPC competition, it is discussed that the schools participating in this competition can directly get the spot in the Regional (Shenyang, Ningxia, Xuzhou) onsite competition without going through the autumn online qualifiers. The number of places is the number of teams participating in Ningxia, and the competition in Ningxia from June 9th to 10th can be determined on the spot. Schools that have already returned the receipt can also add additional places. The way to increase the number of places can also be to turn three-person teams into a two-person teams. For example, two three-person teams can form three two-person teams, and one team can also add one person (500 yuan) to form two teams. On the basis of the unchanged contest fee, the number of regional onsite spots has been increased, and the chance of winning also has been increased (the entry fee for one team is still 1,500 yuan. The entry fee for two or more teams is 500 yuan per person)
We will extend the receipt time on May 12.

While with great relief the claimed free onsite spot was never realized, in the online qulifier for Yinchuan Regional Contest held by NXIST in 2019, NXIST used exactly the same problems as the 2018 NXIST invitational competition. Leading to countless participants cheating and teams solving (actually copying code of) all problems in under 5 minutes.

After this happens, the online qualifier round was generally condemned by contestants, with more than 220 answers to discuss this in zhihu: https://www.zhihu.com/question/343590565.

After wild condemnations, NXIST attempted to hold another online qualifier where the Online Judge failed during the contest and the qualifier was again announced to be effectless and null.

Dr. C J Hwang, ACM-ICPC Asia Director later ordered NXIST to allow all universities interested in the onsite contest to be given free spots, making Yinchuan regional the largest regional of over 400 teams. With most strong teams unwilling to go to the "Joke" regional, weak teams advanced to WF and regional gold medals were send to much weaker teams than usual, leading to general dismay.

III. Corruption and Cheating: 2021

NXIST again hold an regional in May, 2021 with no qualifier round, leading to 499 teams attending onsite. This time NXIST sent 14 teams as official participant to their own regional, where in tradition universities in China almost never send own teams as official teams, not to say more than 10 teams.

While sending many teams may be somehow "acceptable", the teams sent by NXIST were spotted using three laptops per team to compete during the official onsite regional while all other teams used only one computer assigned by NXIST.

See proof in the following images (Codeforce version suffers low resolution, but you can find original ones on Zhihu if you want):

This is an image taken during the official contest by a spectator. Nothing quite wrong, right?

Well, No. When we zoom in to the upper right area, what do we see:

We see NXIST(宁夏理工学院) teams using their own laptops to compete. You may see stars on their team name, yet NXIST later said that the stars were "Just For Fun" and these teams are official. These teams were later awarded medals from the contest.

See discussion on zhihu: https://www.zhihu.com/question/459857672.

While this is already completly mind-blowing cheating to most contestants, clues of a much worse degree is only announced today.

Yonghui Wu announced today in a Wechat group of 499 people:

Just now, the judges and testers of ICPC Yinchuan regional reported that "from the contest archive of only 73% of the submissions, we've found that the code NXIST-team-01 submitted in the 263th minite is exactly the same as the UESTC team submitted in 75th minute. (Completely the same, char by char)"

I have reported to Dr. C J Hwang, ICPC Asia Director and ICPC headquarters about this matter.

I have the following suggestions for NXIST:
(1) Disqualify all teams from NXIST
(2) Apologize to all participating universities
(3) Promise to investigate thoroughly and make the results public.

This is mindblowing cheating, as DomJudge users will know that it is only possible to view somebody else's code via the Jury interface with a Jury or Admin account. It is logical result that very likely, some NXIST personnel helped teams (Which used there own laptops) acquire the submitted code of another team.

This could not be a printed code leak because even with the printed code it is impossible to type "char by char" same, moreover teams never print Accepted code.

See discussion on zhihu: https://www.zhihu.com/question/460422916.

IV. Thoughts

I would like to post this on my main account, but then I am not looking for trouble directed at me.

I know that maybe things isn't getting better after all these years of NXIST making fun of ICPC, but I believe cheating and corruption of such degree calls for words to be spread.

Let's hope for things to get better.