Compilation of Plagiarism Concerns

Hello all,

Since the last two weeks, I have seen multiple people on discuss putting forward their grievances regarding the plagiarism issue. Not only that, many of you have also mailed me your issues hoping that they would be discussed with the admins. Recounting admins stand on plagiarism issues-

“You all must remember that the issue of plagiarism impacts us as much as it impacts you. CodeChef is a community built on trust and cooperation, and any sort of cheating that happens makes the learning experience worse for everyone involved, including us. This means that sometime we have to take harsh decisions.”

So, after a detailed discussion and an intense debate on current scenario I present to you the results of our discussion. It is possible that your question has not been covered, but it is quite likely that it has. I hope this puts your concerns to rest :). If not, is the way to go. (I cannot possibly discuss all of the uncountable individual/special cases I got due to limited time with us and admin’s busy schedule.(

1.“I have been struck by the plagiarism hammer. HELP!!”

Ans: This case was not even worth mentioning to @admin. No details were present. Just a mail stating-

“I got struck with hammer. Please ask admin to undo it.”

Excuse me, but what? You got struck because of your own actions. Sorry, I cannot do anything without more details and I just cannot ask her to undo baselessly. These cases were ignored, and this was imitated to the concerned people by me wherever possible. I trust her hammer good enough that it just rain down its wrath on anyone. The number of mails I received for this category are quite concerning.

2. “My ratings have taken a big fall! Also, it is mentioned that-

Penalties on Plagiarism: Users found cheating will be penalized heavily. The first time they are caught, their ratings will fall by 500 points. The second time, it will fall by 1000, and **they will be banned on the third instance.** This will be done from now on.

Should I make a new account or continue with existing?”

Ans: We have already foreseen this dilemma. Our rating system is what will make us possibly unique here :). When calculating ratings, there is a volatility factor affecting it, which is based on how well users are performing w.r.t. their rating. It will allow a fast recovery of rating if you stick to your old account.

Regarding new accounts, please remember, you are NOT allowed to participate with both accounts (old and new) in a contest. Please keep that in mind. Penalizing people for multiple accounts just for existing (i.e. if the account is not doing anything malicious, not breaking rules) is not in our priority list right now. However, please let be known that, it is against our code of conduct and rules if you possess multiple accounts. At any point, you must be having only a single account.

My Opinion: As long as you possess only a single account, abide by all the rules and regulations, its subjective. Admin did encourage sticking to old accounts. She, however, is not very much against new accounts, provided users take responsibility upon themselves that they are abiding with the rules at all times. No arguments will be entertained if you’re found violating! First mail them and request them to deactivate your older account, and only after that make a new one. Multiple accounts rule is very strictly monitored by them.

Common Consensus: Rating System encourages you to hold on to older account due to volatility factor. Rest is up to the users provided they respect and take the responsibility of following rules. Multiple accounts are strictly not allowed. No arguments for that case. In case users have multiple account, they should contact admins via email immediately so they can deactivate the redundant accounts.

3. “Its first time you are punishing us :(. Can you not give an unconditional pardon to everybody? The community will appreciate it!”

Ans: No, we cannot. Each and Every user was informed of them being caught in plagiarism. They knew the consequences. Granting a pardon will be very unfair to honest people. We heard arguments from everyone, kept a record of the guilty and then penalized them. Everyone was allowed to have a say in their case. Hence, an unconditional pardon is not favourable since this was a fair trial.

We know that you people are sorry. We have been even receiving mails where people who plagiarised in multiple contests say that they’re sorry. But the punishment is necessary. Because, there are cases where despite being caught, and being urged on not to cheat, people cheated and are now coming up with all kinds of apologies. That cannot be accepted or encouraged.

While we feel your words, we cannot be unfair. We have to draw the line somewhere. We, however, hope that this lesson is learnt for future by the concerned people and wish them best for future contests :).

Mod Suggestion: “Can we not do it, at least, for some selected cases where the grievance seems more genuine than rest?”

Ans: We have been thinking about that since past 2 months. It’s just not feasible. While we are very sympathetic to some of the cases you mentioned, it will be very, very logistically expensive and time consuming to go and deal with cases on an individual basis. We made sure that everyone in the plagiarism list was informed latest 3-4 weeks earlier from this time onwards. Most of these cases were seen and dealt with then and there. Even we don’t enjoy giving punishments to our community members, it hurts us just as much :frowning: …but it is necessary to bring fairness to the system and hence, we are forced to act. It will take up too much time and human resources to deal with cases on individual basis, and it can adversely affect plans for future on which we are working. With a heavy heart, we express our inability to deal with cases on individual basis now (after the 3-week window frame which users had) because it is just not feasible.

My Opinion: Admins had a plan, and we were very specific on dealing with all cases in that period. Once that period is over, there can be no going back because it’s just not possible for them anymore. Also, since rules and regulations have been very clear from the start of contest, we do not have any say in the matter. Admin is under no obligation, and hence, these cases depend on her mercy. If she expresses her inability, then we cannot force her to do something. That professionally, ethically and morally wrong. I feel the concerns, but I am sorry. What’s fair is fair. One cannot dodge one’s punishment.

Common Consensus: Unconditional pardon will do more harm than good. Pardon on case by case basis is not possible now, after expiry of the timeframe for that, due to it being very costly resource wise. We have to move on.

4. “I got a mail after 6 months telling that I have been caught in plagiarism. Had I known then that I am being penalized, I would have made a new account. It’s too late for that now.”

Ans: Ideally, this shouldn’t have happened. We will confirm with the concerned department for any error on our part. But that again, doesn’t change the fact that you did break rules. Our volatility system will allow you to regain ratings faster.

a. “I broke rules because I was new and didn’t know the rules and code of conduct!”

Ans: That is not a valid excuse. We are very particular about this. Not only do we make users agree on terms, conditions and Code of Conduct while signing up, we also have rules at every contest page for easy access. Sorry, but we cannot entertain this. As we said earlier, it’s too expensive for us to do that, even if we want to.

b. Some general comments expressing “Punishment after so much time is not good!”

Ans: This is not even mildly acceptable. Similar to discussion on Unconditional Pardon, this will be very unfair. Everyone was informed, and they knew the rules and the consequences.

My Opinion: @admin did express her concern over delay on emails and will inquire into it. But she was very careful in previous step on who to penalize and who to spare. The argument of not knowing the rules is immediately null and void since you agree to it while signing up and rules are easily accessible. Hence, the cases lie completely at mercy of @admin . If she expresses her helplessness over this step being very expensive and potentially delaying their future plans by a great margin, we should respect that.

Common Consensus: They should, instead of getting demotivated from past, look forward to future. Volatility of rating will allow them a speedy recovery. The lesson should be taken to heart.

5. “I missed the time window for argument.” (Not asked as a question, but was a general case I observed throughout the grievances I compiled.)

Ans: Sorry, we cannot deal with cases now since ratings have been updated already. A 1-month time window (3-4 weeks) was more than enough for you to check your inbox once and get back to us. Once the time window is missed, we cannot do anything. This is a good time to remind you all to confirm which email ID of yours is used for CodeChef communication, and to check it regularly.

My Opinion: Expiry of deadline is a serious issue. If you people saw the mails, but still didn’t respond, or for some reason didn’t check the mail, then its solely your own problem. I am sad to say that, but we cannot hold @admin accountable for it. There is no reason to receive the mail and not reply to that. That is, either sheer carelessness, or a belief that “Let them send mails, they aren’t gonna penalize me anyway.” Both of them are unacceptable.

b. “I did not receive a reply to my mail.”

My Opinion: This wasn’t serious enough to be raised. No reply does not mean that they didn’t see the mail. Every mail is seen and accounted for. If even after that your rating fell, then its because your arguments were rejected. You may mail her, with constant reminders, to know the reason.

Common Consensus: Missing of deadline cannot be helped. Each mail is seen and read. None of them are ignored or “lost”, so no reply shouldn’t be taken as “not seen”.

6. “I participated with 2 accounts. Both were mine, but I am caught with plagiarism! Also, I got a penalty for next long, even after that account got deactivated.”

Ans: Participating with 2 accounts in a contest is very serious offence, in fact, it’s the exact thing which we don’t want a user with multiple account to do. We cannot help you here. You ought to have read the rules, which state this very clearly that only a single account will be used for the contest.

My Opinion: Each penalty is independent of another, so they will punish you for each penalty, irrespective of status of that account. This practice, of participating with multiple accounts, in itself deserves a penalty (of having both accounts banned).

b. “My case is more complicated.”

Ans: N/A (This was not raised during meeting. I cannot discuss each individual case separately).

My Opinion: If you missed the deadline, we can do nothing. If the talks are still going on, then try your best, although it seems that the decisions are already taken. There were many cases which were complicated. We cannot have case to case discussions in the meeting. Get in touch with them, if the deadline isn’t missed.

Common Consensus: Participation with multiple accounts is a serious violation. Penalty is irreversible here. Again, we stress people to learn from mistakes and wish them luck for future.

7. ”Can I make a new account and copy solutions of old long challenge and submit with new account?”

Ans: No! That is same as participating with multiple accounts. You will be caught by MOSS for this. We again, recount, the volatility factor of rating to encourage you to stick to your account.

My Opinion: Don’t expect that if you “first create a new account and then ask for suspension”, then your case will be taken “leniently”. Its as good as breaking a rule and asking them to fix it. First obtain required permission from @admin , and then proceed to it. She made it very clear that having multiple accounts is not allowed. I will advise to not to transit from old to new account during a contest.

Common Consensus: No.

8. “What is the basis on penalty? You said it’s 500 for first time, 1000 for next. That’s not followed!!”

Ans: We will put up a detailed blog post telling the updated mechanisms soon. Please be patient till then! :slight_smile:

Common Consensus: A blog post will be put soon.

9. “What are the plans of @admin for future of Codechef, which she mentioned?”

My Opinion: She is probably preparing for Chef’s next birthday. :wink:

The main purpose of the post is to act as a reference or FAQ at the forum. I feel that transparency should exist here. We should know @admin and @admin should know us. Hence, one of the chief aim of this post is to make @admin 's views loud and clear, so that the community can take that as a reference and do actions for optimum results.

I tried my best for each and every case possible. I hope you guys understand that.

Please comment any doubt, concern or suggestion of yours below.

Thanks and Regards,
Forum Moderator


Ratings were not updated properly for May challenge for my account.Plz check it

1 Like

Hi @vijju123 -

I have already mailed, but there seems no response yet.

My case:
I have been penalised mistakenly by the system, while comparing the below solutions:

Please have a look and you will understand how.


I mailed Codechef the same day I got the first mail. But no response from their side and my rating were dropped while comparing these solutions:-

which had only input classes same from GFG. I again messaged codechef and also asked on discuss about this when my ratings were dropped, still got no reply. Its all clear even if you open those two links, still if you still want to say that the mistake is from my side and @admin rejected my arguments, I am sure that the reply mails were not even checked.

I was plagiarised twice. According to the rules, I should’ve been penalized with a deduction of 1500 rating points, but my ratings were reduced to zero.

Also, the volatility issues of users with 0 rating participating in MAY18 experienced very low rating increment. When will the rating update?

Cook-off is due tomorrow, is the volatility issue resolved?

The problem is not with the volatility.
The rating changes are capped with a max rating change computed as 100 + (75/timesPlayed+1) + 100*500/(|R-1500|+500). If it is your 3rd contest and you have been plagiarised 2 times, then also your rating change by at most 150. And this is the worst case. In an average case, it is increasing by around 128-130. Maximum rating change capped needs to be increased for such users to regain their ratings instead of volatility factor.

Our volatility system will allow you to regain ratings faster.

True! You can see it from my graph, I solved 1 question in few contests and left it because I was busy and had to continue 100% attendance but I could easily regain my old rating after that huge drop.

Thanks Codechef for making it more fair to everyone! :slight_smile:

PS - I think online IDEs like ideone should make code private by default. Most of the issues will be resolved by this.

I feel that the volatility factor is working well when you score low, but not when you score high.I had an initial rating of 1100 and after scoring rank 86 in long(div2), I got a +160 only. In the cookoff(div2) I had rank 13, with initial rating 1260, and I got a +170 only whereas, I see people with higher initial rating/lesser rank get higher rating changes.Please do check with the same.

1 Like

@adiabhi what I see is your rating changes in both the contest is the maximum allowed rating change for you in those contests.
In MAY Long, maximum allowed rating change for you was 100 + 75/18 + 500**100/(|1500-1100|+500)=159.72 ~ 160. Even if you would have got 1st rank, then also the rating had changed by 160.
In May CookOff, Your maximum allowed rating change was 100 + 75/19 + 500
100/(|1500-1260|+500)=171.51 ~ 172. Even if you would have got 1st rank, then also the rating had changed by 172.
Rating change is maximum when a person’s rating is 1500.
For those having 0 rating, their maximum rating change will be 100 + 75/(noOfContests) + 50000/(|0-1500|+500) = 100 + 75/noOfContests + 25 = 125 + 75/noOfContests. For a person who appeared in 10 contests, it will not be more than 133. Even if they get the first rank in contests or 500 rank their rating change will be practically the same. Their rating recovery will take a lot of time.


The rating update rate for the plagiarism victims are very poor
in May long my rank was 505 and rating increment was 130
in May Cook-Off my rank was 248 and rating increment was 132!

How is this possible?

You mentioned " When calculating ratings, there is a volatility factor affecting it", if that is true what is the explanation of my rating increment.

1 Like

Do not copy other’s code, if you are not enjoying coding then there are lot of other things to make your life interesting. Thanks to codechef for taking plagiarism seriously.

1 Like

I didnt even get any mail.
pls resolve my issue.
email id is correct on my account
checked spam too.
at least tell me which prob and with whom my soln matched

My cookoff rating was increased by 17 points but overall rating decreased by 173 points . i think there are some problem in the rating system .

Hello all,

I am delighted by the communities response and gesture towards the issue. Nothing is perfect, so its not very surprising if any one of us, out of all the million users, is able to come up with a better idea to deal with current issue.

We are dealing with @admin over how we can resolve, what can be done to provide most relief to users, while also not making things unfair for honest ones. If one of you guys has a nice solution to any of the problems faced by users, or any concerns or doubts, you can write them here at the thread.

For suggestions, you can also mail me at the id given at my profile. If its good enough, I can directly add it to the suggestion list to forward to @admin . Or you can also contact admins at



The rating changes are capped with a max rating change computed as 100 + 75/(timesPlayed + 1) + 500*100/(|R-1500|+500). Due to this, maximum rating is capped up a limit of around 130 for users hit by plagiarism hammer. For such users solving one problem, 2 problems or all the problems causes same change in rating. If rating increment is around +130, it will take almost 5-6 months to regain the ratings, which a user will probably not prefer. He can make a new account silently and get the rating of 1775 in just one contest, which is illegal as per rules. But it will be difficult to identify such users and to identify such users is probably not the top priority. To make things fair so that the affected user need not create a new account, the above capping may be kept large enough (such as +400 or something like this) for users having less than 1000 rating and volatility factor may be increased so that the ratings can be regained in two months of hard work and at least a significant rating change are visible. Some of us may believe that this is unfair to hard working honest people. But what if a user creates a new account and starts performing well in the contests from the newly created illegal account with heavy increment in ratings. The ratings may not feature the better coder at the top. What we have achieved in the process is just a new account and to track such accounts is an overhead. The main motive is not fulfilled which is learning while competing.

My case wasn’t mentioned in the above article. I have been penalised because of the fast i/o reader which i copied from geeksforgeeks as i code in java. Many java users use the same i/o reader. What is @admin opinion regarding this @vijju123 .

Someone in Bangladesh copied my solution, i was using ideone
please look over this:
@admin the guy who actually cheated was not punished however my ratings were dropped by 500 ??? the guy literally copy-pasted my code without even changing variable name :confused: also you can check my other submissions and you can see can easily notice that i often use #define li macro in my code, plus i submitted the code earlier

@Keshav2010 yes…actually same thing happened with me , in my case , someone in China copy-pasted my code from ideone …and yeah , you are right … i had submitted the code first and also all my codes too have a #define section which is unique in all my codes …
my solution and his solution

The max rating change is 100 + 75/(no of contest) + 50000/(1500-rating)
Isn’t this is very low max rating change for a user.
Even if he got 1st rank or 500 rank it is still the same for him. Secondly, if hit by a plagrism hammer, this takes a lot of time to get restored to actual rating the man worths.
Please Someone See to this.


Hey guys,

I know, a lot of you guys have been sending mails and concerns over it. A lot of good suggestions were given at discuss which I gave to @admin. A lot of you were worried about the progress, and asked me about it. At that time, I didnt have any concrete reply so I simple asked you to be patient - “we are looking into this issue.”

@admin thought a lot, and had a discussion with me along with @drpaveen to resolve this issue. I will include minutes-of-the-meet here.

Admin’s Initiation- @admin first explained to me why they applied the 0 rating rule. He said that there are a lot of people who made double accounts - submitting solutions from fake ones and submitting the final AC at the main one (perhaps to make their profile look good). Despite warnings to not to do so by @admin , they continued as no action (i.e rating drop) was happening. This cannot be encouraged! The agenda of the meeting decided was as follows-

  1. Discuss what to do about 0 rating people.
  2. Discuss about the rating penalties.

My Response: I understand the Point of View, but how well does this case represent cases up to national level? Just hearing this case, one would feel “They need very harsh punishments” , but if we look at other cases, we will see the punishment is too extreme. A case in point is the I/O template ones, where people claim that they got no reply.

Admin’s Response: Yes, we accept our fault regarding template cases. If theres any such case where templates were the reason of penalty, we will look into it and restore the rating at the earliest. This should not have happened. For these cases, we cannot rely on MOSS, manual intervention is needed. We will do everything we need to, to make sure these people get their ratings restored.

My opinion- If you have such a case pending, please forward the mail at again so that its not missed out and speedy action is taken. @admin 's inbox has lakhs of mails which he might have to filter and read. Your little initiative can save you a lot of time, and will be convenient to @admin. The forwarded mail should contain all relevant parts, namely , Smruti’s mail saying you’re caught, and your replies. If was no reply from their side despite your timely presentation of arguments, they will immediately look into your case.

The next part was, about punishment.

My Point- The reduce rating to X is extremely harsh than reduce rating by X. Given that any 2 instances, over an indefinite period of time, are enough to reduce rating to 0 , this model can pose multiple problems and dissatisfaction especially if users arent getting reply to their plagiarism mails and/or if genuine users are punished.

Admin’s Point- He explained to me various factors about his decision and what prompted him to do so. Some factors discussed were, their need to punish regular cheaters severely (the punishment must dissuade them). We discussed other models like those followed by CF. Some constraints were like- they need to avoid frequent recalculation of ratings for timely and speedy update of ratings after contest (which gives another constraint on “trade-off between rating updation and time given to user to reply back with their justification” [if CF model were to be followed])

My Argument- The rating of change to X must be fixed. It should ideally be “reduce by” a fix value than “reduce to” 0. For those with 0 rating, we can give them a ‘boast’ like +800 or +1000 to allow them a sensible recovery. Reduce rating to 0 also encourages multiple accounts.

A detailed discussion then followed. Admin said that currently users are sticking to their old accounts despite 0 rating, and inquired me about it. I responded that its because I assured them that we will look into it, and that they believe @admin will give a fair solution in the end. Admin asked then, why in my opinion, reduce by X doesnt encourage multiple accounts- to which I cited that “A user has affection for his hard work he did to build his profile. A -500 wont cause him to throw it away his account. But a reduce to 0 means he is better starting off with a new one, as it will take him almost half a year to just reach 1500 at a optimistic rate of +100-130 per contest.” Admin seems to have taken the suggestion well :slight_smile:

Final Consensus- We decided that the punishment could be changed to something like "For first contest, reduce rating by 500. Increase it per contest the user is caught in future ( upto a max of -800 per plagiarism contest). If after that he reaches 0 rating, then he is on his own. This was, very agreeable to me as well, as its a lot better than reduce to 0 at very 2nd instance, allows for a possible recovery as well. For the users currently at 0 rating, @admin will give something like +K to allow a possible recovery. Exact numbers will be decided by @admin. Do forward your previous mails to them if you are one of the users belonging to this case! For people with double account, its entirely on mercy of @admin. This is one practice he severely wants to discourage. He expresses his hope that this instance will cause such things not to be repeated in future.

We also discussed various measures we can take regarding no reply to plagiarism mails. The problem is, the workload of it is too much for a few people to handle, as they get thousands of mails regarding this topic. He had thought over it and gave his suggestion. He proposed to make this step public, by a thread on discuss or some portal on codechef website. This will increase transparency. Anyone caught will be required to give arguments and justification there, and he hopes that the community will extend whatever help it could to assist @admin in discharging of this duty.I responded positively, as it makes the process transparent. At last, admin assured more community and/or mod involvement in their process so that things go smoothly for the community. He expressed how important the community and ethics are for them, and with that we concluded the discussion.

A blog will be put up by them soon to communicate the final decisions.

This was the crux of it. It wasnt as short as I described above, a lot of discussion, arguments and concerns (which you guys sent me) were exchanged to get to the most constructive solution. I am just telling the crux of it- the actual discussion lasted for over half an hour XD.