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Savior-of-Cross's blog

By Savior-of-Cross, history, 2 years ago, In English

All my recent round experiences are like "code -> code -> code -> ... -> code contest ends".

I think it won't hurt to increase the default contest duration to 3h so that we can have some time to think about harder problems.

Any thoughts?

roxy

(Mendatory Waifu Pic)

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2 years ago, # |
  Vote: I like it +143 Vote: I do not like it

git gud lol

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2 years ago, # |
  Vote: I like it +115 Vote: I do not like it

The "mendatory waifu pic" has encouraged me to agree.

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2 years ago, # |
  Vote: I like it +139 Vote: I do not like it

What about reducing the number of problems

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    2 years ago, # ^ |
      Vote: I like it +60 Vote: I do not like it

    Not viable as the difficulty gradient would significantly increase.

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      2 years ago, # ^ |
        Vote: I like it -75 Vote: I do not like it

      But anybody complaining about difficulty gradient are stupid

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        2 years ago, # ^ |
          Vote: I like it +46 Vote: I do not like it

        ouch

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        2 years ago, # ^ |
          Vote: I like it +77 Vote: I do not like it

        I disagree, high difficulty gradient shifts the round towards speedforcing. And I don't think speedforces rounds are good for learning new things or improving problem-solving skills.

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          2 years ago, # ^ |
            Vote: I like it +70 Vote: I do not like it

          high difficulty gradient shifts the round towards speedforcing

          Difficulty gradient doesn't shift toward speedforcing. Easy problem does.

          I don't think speedforces rounds are good for learning new things or improving problem-solving skills

          https://codeforces.com/blog/entry/98806

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            2 years ago, # ^ |
              Vote: I like it +13 Vote: I do not like it

            Speed forces are bad. You get 5k submissions for a problem in 2-3 mins. This surely doesn't help in learning new things; instead, challenging problems or those in the edu rounds are good. They always help me learn a new concept or a way to solve a particular problem.

            Reducing the number of problems will affect those who are new(like me) because we don't know many concepts, thus different questions on different concepts, one may solve a new problem if they are a good number of questions.

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              2 years ago, # ^ |
                Vote: I like it +24 Vote: I do not like it

              I don't know what you are talking about. You want to learn new concept and solution skills. You don't want problems that only asks you to implement fast. Me too. They are not challenging. So you agree on me and think that challenging problems should be more viable, which means less problems?

              Reducing the number of problems will affect those who are new(like me) because we don't know many concepts, thus different questions on different concepts, one may solve a new problem if they are a good number of questions.

              Um, what do you mean, so you are going to come up with many new concepts during a 2-hour 6-problem contest? That is a very bold proposition actually. You are either genius, or you didn't come up with new concepts.

              Btw, I don't want to touch upon the # of problems in Division 2. We have many new participants and the rating range those contests cover is very wide. But I don't think your logic backs this very well and rather it agrees to mine.

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              2 years ago, # ^ |
                Vote: I like it -8 Vote: I do not like it

              Light don't kill L

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    2 years ago, # ^ |
      Vote: I like it +96 Vote: I do not like it

    This also works

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    2 years ago, # ^ |
      Vote: I like it +14 Vote: I do not like it

    It really depends on your rating whether there are too many problems or not. If you're a high specialist in a div3 round, high CM in a div2 round or LGM in a div1 round, you'll indeed solve a ton of problems in 2 hours and perhaps you'll not have enough time to tackle on harder problems. However, there are many participants (like CMs and lower masters in a div1) who will solve only 2-3 problems and decreasing the number of problems would not benefit them, they would just struggle with the potentially increased problem gradient.

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      2 years ago, # ^ |
        Vote: I like it +20 Vote: I do not like it

      They solved 2~3 out of 6, and now they will start solving 1~2 out of 4. The only difference is that they will start thinking more.

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        2 years ago, # ^ |
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        What then would be with people who solve 1-2 problems? Especially with div3 participants, as they could not choose easier contest

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          2 years ago, # ^ |
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          Well, I'm only talking about Div1 here

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2 years ago, # |
Rev. 2   Vote: I like it +32 Vote: I do not like it

I aryanc403 , fully supports this petition to make the default contest duration to 3 hrs.

Spoiler
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2 years ago, # |
  Vote: I like it -118 Vote: I do not like it

Downvoted because of anime propaganda

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2 years ago, # |
  Vote: I like it +27 Vote: I do not like it

I would not suggest this for Div 2 rounds at all . This will give unwanted people more time to cheat .

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    2 years ago, # ^ |
      Vote: I like it +129 Vote: I do not like it

    They already cheat, I don't think more time will be enough for cheaters to cheat more lol

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      2 years ago, # ^ |
        Vote: I like it -40 Vote: I do not like it

      If more time is given more problems would be effected as the main source will solve more problems in more time and leak them to promote cheating .

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        2 years ago, # ^ |
          Vote: I like it +202 Vote: I do not like it

        Just cancel all future Div 2 rounds. This way, 99% of cheaters will have no time to cheat.

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          2 years ago, # ^ |
            Vote: I like it -14 Vote: I do not like it

          There is difference between no time and less time .And you are suggesting end of codeforces :) .

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            2 years ago, # ^ |
              Vote: I like it 0 Vote: I do not like it

            Please state how much time do you think is optimal and why.

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              2 years ago, # ^ |
              Rev. 2   Vote: I like it 0 Vote: I do not like it

              According to me for Div 2 contests should remain in their current standard time ( 2hr — 2.15 hr) becuase it is sufficient and Div 1 contests can have 3hr time limit based on difficulty.

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                2 years ago, # ^ |
                  Vote: I like it +13 Vote: I do not like it

                As I see it, cheaters don't need more than 1 minute do copy-paste solutions and submit. Sure, longer contests means the source of leaked solutions would solve more problems, but so would honest participants. Why would that affect the difference between ranks of cheaters and non-cheaters?

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                  2 years ago, # ^ |
                    Vote: I like it -35 Vote: I do not like it

                  Let me explain you . If any solution is leaked in somewhere as the time increase the amount of cheaters copying that increase and it is not linear , in first 10 min if 5 people cheated that ,in next 10 min more than 20 people will cheat and as time increase the no of people . But no of trusted participant solving mroe problems is linear.

                  And trust me with this . I am telling from experience from no of contest I have given .

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                  2 years ago, # ^ |
                    Vote: I like it +34 Vote: I do not like it

                  Interesting. Why?

                  How is the data collected?

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                  2 years ago, # ^ |
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                  How cheaters cheat ? You will not understand this issue as you all ( almost everyone here talking ) are from div 1 and there is not much cheating happening so you guys are not effected by this at all . But for some one like me my rank drops like 1000,2000 or even 3000 in last 20-30 min of contest .

                  I would repeat again 3hr contest is not good at all for Div 2 , it might be suitable for Div 1 . You can take a poll and I can tell more than 99% of Div 2 guys don't want contest to be more than current standar time .

                  All the div 1 guys here telling on behalf of div 2 which is wrong.

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                  2 years ago, # ^ |
                    Vote: I like it +8 Vote: I do not like it

                  Git gud lmao All of you nimcompoops forget that plag check is a thing, but out of commodity you prefer to blame cheaters for your poor results. Since there are succesful people in div2, that really should point out that the main issue for your poor results is.. you. Stop blamimg cheaters and your life will be significantly happier

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                  2 years ago, # ^ |
                    Vote: I like it +31 Vote: I do not like it

                  I asked you a specific question. Can you answer it?

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                  2 years ago, # ^ |
                    Vote: I like it -6 Vote: I do not like it

                  Umm, I think what that wizard guy is trying to say is that there are bound to be quite a few people who first try to solve a problem and after being unable to solve it, decide to cheat (they wait because apparently the solutions need to be 'bought' and people resort to buying only if they are unable to solve the problems themselves). Also the entire process of first acquiring the solution and then modifying (obfuscating) it should take some time. So as the contest progresses, the number of actual participants will start decreasing and the number of cheaters will start increasing. The longer the contest is, the more severe the effect, and considering how in even the short-length codechef Div.2&3 rounds the number of solutions for the medium difficulty problems sometimes even almost double in the last 10-20 mins, I think that guy has a point.

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2 years ago, # |
  Vote: I like it +94 Vote: I do not like it

Yep, would appreciate a bit longer contests as well, as I don't wanna git gud in speed.

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2 years ago, # |
  Vote: I like it +361 Vote: I do not like it

It's already difficult to find 2 spare hours to participate. Maybe only some contests could be made longer?

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    2 years ago, # ^ |
      Vote: I like it -85 Vote: I do not like it

    I can only imagine that if you can afford 2 hours on a Saturday morning/evening/night but can't afford 3 hours, you probably have more important things to do and shouldn't be doing the contest in the first place...

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      2 years ago, # ^ |
        Vote: I like it -21 Vote: I do not like it

      ^

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      2 years ago, # ^ |
        Vote: I like it +380 Vote: I do not like it

      And by induction, everybody should spend 69 hours competing.

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      2 years ago, # ^ |
        Vote: I like it +29 Vote: I do not like it

      Different people have different schedules and your opinion (that one extra hour shouldn't matter that much) only reflects how limited your perspective is. And excuse me, who do you think you are to judge what people should do with their time?

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    2 years ago, # ^ |
      Vote: I like it +89 Vote: I do not like it

    Yes, I agree. For example, only globals

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      2 years ago, # ^ |
        Vote: I like it +13 Vote: I do not like it

      At this point most div1 rounds are either global or sponsored rounds so 3h it is then.

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        2 years ago, # ^ |
        Rev. 2   Vote: I like it 0 Vote: I do not like it

        before start you choosing duration koeficient and after contest your points multiplied by its inverse divided by it

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          2 years ago, # ^ |
            Vote: I like it +80 Vote: I do not like it

          I choose 4 mins then and hope to solve A

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            2 years ago, # ^ |
              Vote: I like it -16 Vote: I do not like it

            ok instead divide rating change by koef

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2 years ago, # |
  Vote: I like it +60 Vote: I do not like it

While I mainly support this, just a small note, which should be obvious since you're from Korea, is that aside from maybe Russia, Western Europe and maybe India, Codeforces contests' time are pretty unfriendly for participants in a lot of countries (for example in my place most contests ends around 23:35). It would be pretty torturous to keep your mind functioning until 12:35/1:35 (or massively fuck up your sleep schedule, which is IMO equally bad), so this would further increase the wedge between Russia/Western Europe and the rest of the world. Aside from this there is generally no objections, but I think changing contest duration to 3 hours would be best if accompanied with changing starting time to that of AGC, which would allow participants from both East Asia and Europe to participate somewhat comfortably.

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    2 years ago, # ^ |
    Rev. 2   Vote: I like it +49 Vote: I do not like it

    How can contest time be ok for Russia and Western Europe, but not ok for Eastern Europe which is in between?

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    2 years ago, # ^ |
    Rev. 2   Vote: I like it +12 Vote: I do not like it

    I always think this is stupid. Nap before contest if you think you'll be tired. I wish contest time in America was then, that is when I practice anyway. And at least contest isn't during typical work/school hours for y'all.

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      2 years ago, # ^ |
        Vote: I like it +39 Vote: I do not like it

      I mean this doesn't work for everyone, I would not be able to take a nap spontaneously to take a contest for example

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2 years ago, # |
  Vote: I like it +7 Vote: I do not like it

I don't know about duration, but I want the time to be shifted 1 hour earlier.

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2 years ago, # |
  Vote: I like it 0 Vote: I do not like it

I don't like it, if only the time is made long but other things kept unchanged.

  1. Current codeforces rounds already ruins my sleep schedule a lot. Increasing contest time and not changing the starting time destroys sleep even more.
  2. This 2-hour duration is quite comfortable and, somehow exciting. It motivates me to practice solving problems fast.
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2 years ago, # |
  Vote: I like it +92 Vote: I do not like it

I have a similar experience with recent rounds, but I think it is clouded by the fact that almost all recent rated rounds (for Div. 1) have been combined. Several of these combined rounds had unusually short lengths: Good Bye 2021 and round #758 were only 2 hours, while Hello 2022 was not much better with 2 hours and 15 minutes.

Combined rounds have an infinite number of problems and it takes a lot of "code -> code -> code ..." before we get to the problems that are interesting for us. If the contest is short, it easily creates the effect of "code -> code -> code -> ... -> contest ends".

The last round was not combined (for the first time since mid-November!) but it was a rather easy one: the slowest person to solve ABCD1D2 got a performance of only ~2500. Compare this to ~3000 in #752 and ~2650 in #751.

In conclusion I think that the sense of "code -> code -> code -> ... -> contest ends" is created by having to solve a lot of easy problems before you get to the interesting ones. The solution is to reduce the number of combined rounds and create more contests where a grandmaster is expected to solve about 3 problems.

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2 years ago, # |
Rev. 2   Vote: I like it +19 Vote: I do not like it

I have similar experience, but think the duration doesn't matter much, since the cause is too many heavy implementation problems. In addition, 3hr rounds might scare away newbies.

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2 years ago, # |
  Vote: I like it +3 Vote: I do not like it

I agree.

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2 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Yes, it would be really useful for lower-rated participants like me, as they would get more time to solve problems. In the present scenario, I am still working towards higher difficulty level problems and the contest time gets over. If the contest duration is larger, I will most likely be able to solve the problems that I can potentially solve and would be stuck only on the problems where I can't think of ideas.

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2 years ago, # |
  Vote: I like it -39 Vote: I do not like it

In India contest time overlaps with dinner time (8pm — 10pm), Making all contests of 3 hours wont be a good idea ,atleast for me, also I am a specialist

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2 years ago, # |
  Vote: I like it -25 Vote: I do not like it

I think that the problem of having all the contest time eaten up by easy/uninteresting problems which are implementation heavy only effects high rated programmers since div. 2 contestants usually are able to solve problems up to their programming skill. If you take a look at the most recent div. 2 you can see that only 6 people AC-ed all the problems. Maybe increasing the time limit only for div. 1s would be a better solution because the majority of div. 2 contestants would have nothing to do the extra hour since the rest of the problems are well above their level.

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    2 years ago, # ^ |
      Vote: I like it +32 Vote: I do not like it

    I believe there are no such thing as "problems above your level", there are just problems where you take X amount of times on average, and you tend to solve it if X <= contest duration. So I don't see how what I'm suggesting is irrelevant to div2 users.

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      2 years ago, # ^ |
        Vote: I like it +163 Vote: I do not like it

      i believe there are no such things as "problems above your level", but there are such things as "problems above my level"

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        2 years ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        i, on the other hand firmly believe that there are no such things as "problems above your level", but there are such things as "problems above my level"

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    2 years ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    totally agree with you...As a lower-rated coder, I never felt that if I would have more time I would have done more problems...So It's my request not to increase the default contest time as it would negatively affect the lower-rated coders and only benefit those who are competing for top ranks, I mean high-rated coders.

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2 years ago, # |
  Vote: I like it +62 Vote: I do not like it

I could easyly spend 12 hours on the problems of each contest. But that I think is no good advice to increase the contest time. The other way makes more sense. It should be agreed on the duration of the contest, then try to find the optimum problemset for that contest time.

And actually, this is how it works currently. So, no need to change. For me more than two hours does not make a better contest.

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2 years ago, # |
  Vote: I like it 0 Vote: I do not like it

As a Roxy simp and noob at speedforces, I would greatly appreciate this.

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2 years ago, # |
Rev. 2   Vote: I like it +1 Vote: I do not like it

No please. We already have decent enough number of 2.5 — 3 hour contests and I usually avoid them because 3 hours is too much for me.

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2 years ago, # |
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I think extending contest time will result in more cheating in the rounds. Also, suppose some solutions to the problems are implementation heavy. In that case, they are the same for everyone, so they don't negatively impact your rank or rating in any manner, and you can upsolve them after the contest. According to me ,instead of increasing the contest time, we can try work on our speed by giving more and more virtual contests and getting better with time.

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2 years ago, # |
  Vote: I like it +15 Vote: I do not like it

agree,but make the start time 1 hr earlier please or the Chinese coders will go to bed at 1:35 : (

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2 years ago, # |
  Vote: I like it +21 Vote: I do not like it

3h may be too much. But making default time 2.15 seems to me like a very reasonable idea.

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2 years ago, # |
  Vote: I like it +129 Vote: I do not like it

It's already hard for me to find a time to participate a 2-hour contest, and now I find this blogpost :(

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2 years ago, # |
  Vote: I like it +8 Vote: I do not like it

yamitikoda saiii!... means yes lol

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2 years ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

I'm in

Always felt that 120 min here or even 100min at atcoder is too little

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2 years ago, # |
  Vote: I like it +20 Vote: I do not like it

I feel 3hr is too much..

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2 years ago, # |
  Vote: I like it +18 Vote: I do not like it

People really get this much free time?
Maybe make 3 hrs in holiday

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    2 years ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Surely I would prefer all contests to be on holidays. After all, on workdays I have this thing called work...

    Well, I do remember arguments against but it doesn't change my preference

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2 years ago, # |
  Vote: I like it +77 Vote: I do not like it

I'll play devil's advocate and put forth another reason against extending contest duration that isn't just "I'm busy and don't have time for longer contests." Codeforces's format has always taken a more speed oriented approach. Problem points decay over time and solving more or harder problems doesn't always mean you beat someone who solved less or easier problems. Part of what makes competitors higher rated isn't just their ability to upsolve hard problems, but their ability to successfully solve these hard problems in contest. So given all of that, 2 hours makes sense as it gives enough time for top competitors to full solve but is also short enough to be speed-oriented.

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    2 years ago, # ^ |
      Vote: I like it +10 Vote: I do not like it

    That's a really nice argument, and the only argument against extending contest time I see in this thread that I can bare with.

    Tho I'd say 2h is hardly enough for top competitors to full solve judging from recent round scoreboards, unless there's a reused problem.

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2 years ago, # |
Rev. 2   Vote: I like it +10 Vote: I do not like it

maybe, but contest starts at 22:35 UTC+8(china) and ends at ~24:35 which is acceptable lengthen it to ~25:35(1:35) maybe a bit too late

so just delete problem A or even B in every div

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

That sounds very familiar, This is the usual exam duration (3 hours) and 3 hours looks ideal to me. We can even add more problems to make difficulty gradient better.

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2 years ago, # |
  Vote: I like it +7 Vote: I do not like it

I'm in

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2 years ago, # |
  Vote: I like it +56 Vote: I do not like it

AGC's are waiting for you!

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2 years ago, # |
  Vote: I like it +138 Vote: I do not like it

I took a look at the durations for all Div 1 rounds since last year (starting from Codeforces Round 694 (Div. 1)) and these are some stats on this topic:

  • There are 36 rounds in total, of which 19 are Div 1 only and 17 are Div 1 + Div 2.
  • The most popular duration is 2h15 (11 rounds). 2h and 2h30 come close with 9 and 8 appearances.
  • The average duration is 2h23.

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2 years ago, # |
  Vote: I like it +2 Vote: I do not like it

I have been requested to bump the blog