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stefdasca's blog

By stefdasca, history, 5 years ago, In English

Given MikeMirzayanov's Div 4 contest announcement and Errichto's suggestion for lower bound for Div 2, I decided to come up with some ideas to further improve this update.

Firstly, I'd like to say that Div. 4 contests are a great addition for people who have absolutely no idea about competitive programming and the ability of being able to solve more than just one problem will definitely make new people more confident when it comes to problem solving.

However, this change will definitely bring lots of new contestants to Codeforces, and some measures will have to be taken in order to deal with the new change.

As Errichto suggested, a rating lower bound would be beneficial because it partly solves the rating inflation and also because it will generate less queue.

Starting from this point of view, I'd like to suggest further improvements which can be made in order to make the platform even better:

1) Since we have parallel div1/div2 rounds, maybe we can also have parallel div2/div3 and maybe div3/div4 parallel rounds as well. Obviously, some lower bounds will have to be implemented, but this is not much of an issue, because the current lower bounds for colors should make the splits easy to implement.

2) Maybe let other people become problemsetters for div3 as well, there are plenty of people who want to become Codeforces problemsetters but maybe their tasks are not considered good enough for a div2 round because of one reason or another. Since div3 tasks are meant to be more standard, the problemsetting criteria can be less harsh.

3) Given the recent inflation of ratings, which is also a problem and if none of these suggestions will be implemented, this is going to become a major problem, since one can become purple with div3 rounds(look at andryusha_na_knopke for proof), maybe also change the color thresholds for each color.

What do you think about these possible new changes, would they be useful to make the Codeforces experience even better in this era of dramatic growth? I'd like to see your opinions in comments.

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5 years ago, # |
  Vote: I like it +9 Vote: I do not like it

As a note regarding the color revolution, a good idea would be to rise up the color thresholds, but keep the current division limits.

As an example, rise the master title to 2200 or some other bigger number, but keep the div2 only rated only up to 2099.

Obviously, these numbers will have to be changed all over the ratings, in order to avoid situations like International Master have just 100 ratings width.

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5 years ago, # |
  Vote: I like it +5 Vote: I do not like it

I definitely agree with these ideas. It is quite rough to begin CP on a website like CodeForces when your first couple rounds are a tough Div. 2 or even sometimes Div. 3. My own concerns were about the stress on the CF infrastructure, especially with the recent queue problems and outages we have experienced since Div.4 rounds will surely bring thousands of new people to CF. Overall, any growth to the CF community is welcome in my opinion, and splitting up divisions more thoughtfully has been long overdue as well.

As a participant of CF, I have observed the growth of the website during the pandemic, and think that although there are a lot of new green/grey participants that may seem to "saturate" the lower rankings of contests, I haven't observed significant rating inflation except maybe a small trend or for lower rated contestants which isn't a huge concern in my opinion.

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5 years ago, # |
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since one can become purple with div3 rounds

I think they have to be at least in top 10, which usually means they solved all problems. The hardest problem in Div3 is at least as hard as Div2D, and if one does Div2 ABCD (with reasonable penalties) consistently for 4-5 rounds, then they too can cross over to Div1 (as I hope to do as well, soon).

But yeah, maybe capping it to 1800 would be better.

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5 years ago, # |
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What I feel is rather than having a Div.4 round (which is more or less like Div. 3), changing the current Div.3 and having them for only Newbies and Pupils should do. Specialists and Experts will focus on Div.2 and higher ups for Div.1. If required, purples can join Div.2 and Div.2 problems can be made a bit harder. For me, Div.4 is just too much after having Div.3 and Educational contests which are simpler than normal contests. Of course, at the end it is MikeMirzayanov who has to decide and experiment. And yes, Div.4 will surely give a huge number of new problem setters as well. Hope to see something fruitful from this experiment.

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    5 years ago, # ^ |
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    IMO, Div. 3 are interesting enough for specialists as of now.

    Also, many participants on Codeforces are beginners and many people solve just AB in div3.

    Problems are meant to be meaningful for the participants, otherwise we would just waste tasks.

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      5 years ago, # ^ |
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      Just solving two problems in a round is a bad thing. Why? Div.1 participants experience this all the time.

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        5 years ago, # ^ |
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        There are plenty of things to say about this state of affairs as well, after all I'm one of those Div. 1 participants who usually solve only AB as well, but in my opinion, given the current system, the only way to actually fix this is by rebuilding the entire rating system, with more divisions and less tasks in each contest.

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5 years ago, # |
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I think Div 4 is a cool idea, but I am slightly dubious about how interesting the Div 4 problems will be. There's a chance that Div 4 might just become a CF variant of Leetcode contests (mostly well-known or slight variations of well-known problems). Of course, I can't say for sure until the first Div 4 contest happens.

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5 years ago, # |
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Maybe let other people become problemsetters for div3 as well

I think it's a bad idea.

Div3 problems are quite easy to create (since they can be relatively standard), it's way more efficient to have one or two regular authors instead of coordinating new authors, having to debate about tasks, helping them to understand Polygon, checking the strength of their tests, etc...

Having to review and coordinate div3 proposals (there would probably be a large number of them) would be time-consuming for coordinators, and make the queue situation even worse.

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    5 years ago, # ^ |
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    On the other hand, it's an easy start for new setters and might lead to more creators of div1 rounds.

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5 years ago, # |
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Idea: Everyone with rating of 150/200 points higher then the upper bound of division x will be able to set problems for that division. They may prepare their problems on polygon and use a special page/PM to submit them.

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    5 years ago, # ^ |
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    "Everyone with rating of 150/200 points higher then the upper bound of division x will be able to set problems for that division." Really? I'm pretty sure that experts with rating 1750~1800 can't easily solve div3 F. How can they set problems?

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      5 years ago, # ^ |
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      I am not saying a complete problemset, they should be able to submit their individual problems, for example they can set Div.3 Ds and Es

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5 years ago, # |
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I disagree with you!!!

I'm a genious!!!

I like to write contests and write!!!

Yeah, I have shiza, but you can't laugh on my disability and illness!!!!

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5 years ago, # |
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5 years ago, # |
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I think having Div3, Div2 at the same time is better where the First 2 easy problems are in div3, Following 3 problems are common and Div2 having 2 difficult problems.