New Rating Divisions (Div1/Div2) on Codechef

Hey Guys! :slight_smile:

As we all had been suggesting to codechef since past many months to have a separate rating divisions, i.e. separate Div1/Div2 contests, the devs have been working hard since past few months to implement it. Lo and Behold! As evident from yesterday’s sneak peek given on Codechef’s Facebook page, the feature is live, starting from current long challenge. Thats Chef’s way of surprising us on his 9th Birthday :slight_smile:

What is it primarily?

Speaking of the feature in short, it is as follows-
The users, and the contests, will be divided into 2 divisions. Users with rating <1800 will be allotted Div2, while users with rating \ge1800 will be alloted Div1. Each of the contests, like, long, cookoff and lunchtime will now have 2 parallel contests running- one for each division. Div2 will have easier problems than Div1.

Why this change?

  1. It was user requested and Chef listens to all the suggestions he gets :stuck_out_tongue:
  2. A user will be rated on basis of participants in his own division. This ensures that ratings reflect your skill closely.
  3. User will get problems with difficulty suited to his taste. No more complaints to excessive spice or too bland and boring :stuck_out_tongue: :wink:
  4. This system can potentially allow codechef to have more external rated contests by making them rated for Div2

What exactly changes?

1. Contest

  • Each contest has been divided into 2 divisions. Div1 and Div2.
  • A user can participate in contest of only his division. Example- A Div2 user trying to participate in Div1 contest is not allowed. Same for vice-versa.
  • In case of only Div2 rated contests, if unofficial participation is allowed, Div1 users may participate- this depends solely on the discretion of @admin /contest organizer.
  • Although Div1 and Div2 are two different contests with separate ranklist, they do share some common problems. The contests have some unique problems, and some problems shared with other division. Example, Div2 this long has, first 3 problem of as unique, while rest are shared with Div1. Similarly Div1 has last 3 problems as unique. (First 3 and last 3 w.r.t. difficulty scale)
  • Each Division will have 8 problems, out of which, one will be challenge or tie-breaker problem. (*Number of problems can change in future.)

2. Rating Calculation-

  • Rating of each user is calculated based on participants of his division. Submissions in Div1 will not affect rating of Div2 and vice-versa, EXCEPT in case of plagiarism.
  • This also means that the contest leader board will only cater to, and show rankings of participants of its own division.
  • However, MOSS and plagiarism checking will be applied to both contests as a whole(just like it happened till now.). Meaning, if for a common problem, a Div1 guy’s code matches with Div2 guys code , both of them will be penalized.

3. Prizes-

  • The prizes for Div1 remain same as normal contest before. Prizes for Div2 are changed. You can refer to here for exact changes.
  • Any use of unfair means will lead to penalty, whether in form of laddus, cancellation/forfeiting of prizes, and/or permanent suspension of account.

Any questions, queries and suggestions on above are welcome. We will try to edit in more information to suit your queries as and when applicable. :slight_smile:

With Regards


What if some school student in div1 purposely decreases his ratings to become div2 and win?

Div 2 prizes are reduced to one-third for this reason. If we see such instances, adjustments will be done to decrease prize further/kill that motivation of malpractice. Thats why I would urge the community to do fair play- malpractices will likely just reduce the prize.

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No one will do that. The prizes in div2 are like 50 laddus.

@mathecodician - We cannot assume that no one will do that. Some people feel they are too smart.

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A small edit: “>=1800” will be div1 whereas it is currently “<=1800”

Corrected that @ista2000 . What did you edit @mathecodician? :o

Number of questions per div in long challenge has been reduced to 8 or 2 more questions will be added?

Reduced to 8 @abdullah768

kya kia @admin ne … ab red coders ke saath compete karne me maja nahi aayega
huh !! not good


u r unrated anyway


it would be better that admin should give all his charges to some other
codechef me ab wo pehle wali baat nahi rahi

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Well this is a nice change.Also consider this -

Another important and simple feature will be button for copying test cases , just like the one introduced on codeforces , it really helps!!


i am thinking for long but i couldn’t get !! why cc did this !
basically u have to solve the same 10 problem in div1+div2 combined
which we earlier used to solve in whole .
now 1-3* will have to solve 1-8 ques
and 4-7* will solve 3-10 questions
agar combined hi rehta aur 4-7* wale addition 2 easy question bana lete to problem kya thi
@vijju123 @admin
&& math wale bhai tu bhi thora soochne

Would’ve been better if were 10.

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Stupid question - if rating increases, one gets to Div 1 right ? ( After Rating Increment ) ( For next month )

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The thing is, the pro coders complained that first 3-4 questions were boring, to them, because they were too easy. They had to do it because of points anyhow. Then, rookies complained of last few problems being overly tough and wanted easier contest. Pro coders wanted just the opposite.

If we segregate into divisions,then- if need persists, we can give div1 harder problems not shared by div2 and vice versa. Also, problems can change in future, perhaps it can become 10 problems to div 2 and 10 to div1 with minimal/nil shared problems.


Suggested to @admin. She liked it. Thanks.

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good then ! but problems is div 1 should not be too tough in future
@admin should take care of it