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TheScrasse's blog

Codeforces Round 975 (Div. 1, Div. 2)
By TheScrasse, history, 5 days ago, In English

Ciao, Codeforces! We're glad to invite you to take part in Codeforces Round 975 (Div. 1) and Codeforces Round 975 (Div. 2), which will start on Sep/27/2024 16:35 (Moscow time). You will be given 6 problems and 2 hours and 30 minutes to solve them in both divisions. Some problems will be divided into subtasks.

UPD: the time has been changed to Sep/27/2024 16:35 (Moscow time), which is different from the time announced before. Please note the unusual starting time.

This round is based on Italian Olympiad in Informatics (OII) 2024.

The problems were authored by lorenzoferrari, wksni and me.

We would like to thank

Score distribution:

  • Div. 1: $$$500 - 750 - 1000 - 1500 - (2250 + 750) - (1500 + 1500 + 1500)$$$
  • Div. 2: $$$500 - 1000 - 1750 - 2000 - 2250 - 3000$$$

We hope you'll like the problemset!

  • Vote: I like it
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  • Vote: I do not like it

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5 days ago, # |
← Rev. 2   Vote: I like it +79 Vote: I do not like it

As the first commenter.. thanks for the div1 contest.

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    4 days ago, # ^ |
    ← Rev. 5   Vote: I like it -95 Vote: I do not like it

    but you are pupil, so how is div1 relevant?

    please downvote. wow -91. Thanks downvoters. I beat you attractors in your own game

    update: please more downvotes i hope it becomes -100.

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      4 days ago, # ^ |
      ← Rev. 3   Vote: I like it +90 Vote: I do not like it

      That's ok, but I love div1 contest, I'm a 6 stars in codechef and I just started contest in CF. Besides, it's fun to watch the tourist and LGMs play. Thanks.

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        3 days ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        you'll watch me too, haha! can I raise my rating in div1 contest?

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

          I'll watch you, sir, but in div2. That would be fun too.

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

            so, you mean I can raise my rating in div2 contest as a newbie?

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

              Sure. As a dev tutor.

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

                I have another question. my contribution is -5. why?

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

                  CUZ you comment all day.

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

                  thx for your kindness. I want to become friend with you. give me your social link like discord or telegram.

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5 days ago, # |
  Vote: I like it +87 Vote: I do not like it

do i wake up at 1 am to do this?

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    5 days ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    There's no option, bro. isn't it div1..

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    4 days ago, # ^ |
      Vote: I like it +4 Vote: I do not like it

    The starting time is (on purpose) similar to that of the onsite contest.

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    4 days ago, # ^ |
      Vote: I like it +124 Vote: I do not like it

    Well, you kind of forget that there does exist a certain part of the globe where they always had to wake up at 12 AM to take contests

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      4 days ago, # ^ |
      ← Rev. 2   Vote: I like it +13 Vote: I do not like it

      Hopefully in the future we will have more contests for different time zones.

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    3 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Now , you don't have to

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5 days ago, # |
  Vote: I like it 0 Vote: I do not like it

I'm sure this round will be cool !

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5 days ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

This is an odd timing tho, anyways this will be my first contest

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5 days ago, # |
← Rev. 2   Vote: I like it -11 Vote: I do not like it

no offense or anything but i never understand your round editorials so please focus on them being good this time

edit : also include proofs most recent rounds i feel like we get the solution thrown at us with no proof or anything attached last round problem D is an example

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5 days ago, # |
  Vote: I like it -25 Vote: I do not like it

Cool, another round I won't be able to attend

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5 days ago, # |
← Rev. 2   Vote: I like it -26 Vote: I do not like it

‎‎‎‎‎‎‎‎ㅤ

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4 days ago, # |
← Rev. 2   Vote: I like it -42 Vote: I do not like it

1am?

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4 days ago, # |
  Vote: I like it +7 Vote: I do not like it

is it possible to reschedule it to 20:05 utc+5.5 on friday, if then please do it. otherwise no problem,I will have to do it virtual, because in daytime i will be in my office for friday, or you can make it saturday the same time. It's not a problem to miss contests for unavoidable reasons but if possible, I don't want to miss it.

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4 days ago, # |
  Vote: I like it -34 Vote: I do not like it

People who use AI, why are you doing this? Besides the fact that it is forbidden, it also kills all the interest of the competition. What is the interest of such submission if in the end they will not give anything in terms of experience, and the account will still be banned.

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    4 days ago, # ^ |
      Vote: I like it +48 Vote: I do not like it

    Why do you have to bring up this topic? AI users will not stop using AI after reading your comment.

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4 days ago, # |
  Vote: I like it +1 Vote: I do not like it

that is 11 in the morning for me ._.

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4 days ago, # |
  Vote: I like it -58 Vote: I do not like it

I hope the time will be changed to 22:35(UTC+8:00) as usual.

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4 days ago, # |
  Vote: I like it +8 Vote: I do not like it

Great time for me. Hope for more.

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4 days ago, # |
  Vote: I like it -12 Vote: I do not like it

I think tourist will drop out of Tourist in this contest

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

I want to know if I can participate div.1 with the score as low as me and if I can only participate div.2 or I can participate both.

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    4 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    You can participate in only div2 and not div1, I think for div1 lower bound is 1900

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4 days ago, # |
  Vote: I like it +9 Vote: I do not like it

1:35 pm for me it will be great I am gonna skip college class that day

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    4 days ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    You can skip your college class, but for me in our country ,the contest will begin at night and it will finish until most people has been slept. So I should increase my CF score by staying up late.

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4 days ago, # |
  Vote: I like it +3 Vote: I do not like it

finally, a contest at a good time for Americans

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Is the score distribution for Div1 and Div2 correct ? Since when did Div2 C become 1750 rated ? I think there's been a typo ?

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    4 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    so what does that mean if its set at 1750 ?

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      4 days ago, # ^ |
        Vote: I like it +5 Vote: I do not like it

      Generally Div2 C's have points of 1250-1500. More points mean the problem is likely to be more challenging.

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      3 days ago, # ^ |
        Vote: I like it +1 Vote: I do not like it

      It means it will be a speedforces round with 10k+ submissions on B and <4k on C.

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4 days ago, # |
  Vote: I like it -30 Vote: I do not like it

why the unusual starting time ?

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4 days ago, # |
  Vote: I like it +4 Vote: I do not like it

Unfortunately, I have school at this time :(

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4 days ago, # |
  Vote: I like it +12 Vote: I do not like it

Weirdest way to skip a Div1: possibly coinciding with team meeting at work...

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4 days ago, # |
  Vote: I like it +4 Vote: I do not like it

cool time in general, but not in friday XD

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

he really has the last name "ferrari", impossible.

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4 days ago, # |
  Vote: I like it +19 Vote: I do not like it

As a tester, I hope no one will be using AI instruments (^˵◕ω◕˵^)

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4 days ago, # |
← Rev. 3   Vote: I like it 0 Vote: I do not like it

My reaction when I open at 17:35 to enter the contest:

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4 days ago, # |
  Vote: I like it +9 Vote: I do not like it

As a tester, I wish all of you a good luck!

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4 days ago, # |
  Vote: I like it +60 Vote: I do not like it

Div1 is too few. More plz :)

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

Why use Ciao instead of Ciallo(✿◡‿◡)?

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Div 2c 1750??? Something is cooking...

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

The starting time means i probably can't participate but good luck to others!!

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4 days ago, # |
  Vote: I like it +1 Vote: I do not like it

Oh no, it’s 16:05 in China. I am in school that time, bad luck to miss a div1 again.

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4 days ago, # |
  Vote: I like it +4 Vote: I do not like it

As a tester, I'm so happy to be able to say that!

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4 days ago, # |
  Vote: I like it 0 Vote: I do not like it

my strategy: stare problem C for 30min if ! solvable goto bed

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4 days ago, # |
  Vote: I like it -18 Vote: I do not like it

I'd participate if it was 6 hours or a day later. This is a big F you to students and working Americans and Europeans.

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Aren't the ratings for the rounds swapped?

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3 days ago, # |
  Vote: I like it -12 Vote: I do not like it

swap div1 with div2

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    3 days ago, # ^ |
      Vote: I like it +19 Vote: I do not like it

    Div. 1 and Div. 2 use different problemsets, so comparing their scores doesn't mean anything.

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3 days ago, # |
  Vote: I like it +41 Vote: I do not like it

Waiting a month for a div1 only to get a 4am round :(

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3 days ago, # |
  Vote: I like it -7 Vote: I do not like it

isnt the scoring distribution for div 1 usually higher

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    3 days ago, # ^ |
      Vote: I like it +16 Vote: I do not like it

    Not necessarily, and there is no reason why it has to have higher scores, as Div. 2 and Div. 1 are completely separated.

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3 days ago, # |
← Rev. 2   Vote: I like it -11 Vote: I do not like it

Wow, this is a very suitable match time for our Chinese compatriots, and I am looking forward to having a good performance ：)

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    3 days ago, # ^ |
      Vote: I like it -28 Vote: I do not like it

    I love U ❤️. There is a love story between us ❤️.

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3 days ago, # |
  Vote: I like it -8 Vote: I do not like it

Now I will give div-1 or div-2? Div- 1 looks more scorable than div-2. And div-1 rated range?

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    3 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Expert and below can participate only in Div. 2. Div. 1 is for Candidate Master and above.

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    3 days ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    point values are not representative of absolute difficulties, only the relative difficulties (sometimes they too might be wrong because authors mispredicted)

    it seems that d2C = d1A in this round, you want to get C as first problem?

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

very interesting distribution for div1.....maybe consider increasing time?

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3 days ago, # |
  Vote: I like it -12 Vote: I do not like it

Why Flamire is the $$$\text{V}\color{red}{\text{IP}}$$$ tester but le0n isn't?/kel

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

    $$$\text{L}\color{red}{\text{GM}}$$$ ? (bruh he's not even tester)

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      3 days ago, # ^ |
        Vote: I like it -12 Vote: I do not like it

      Nonono.. bro, $$$\color{black}{\textsf{l}}\color{red}{\textsf{e0n}}$$$ is going to be LGM very soon.

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    3 days ago, # ^ |
      Vote: I like it +29 Vote: I do not like it

    Because he didn't test.

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    3 days ago, # ^ |
      Vote: I like it +22 Vote: I do not like it

    Because I didn't test.

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

Every time i open CF, the score distribution changes.

UPD — They changing time now as well.

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Why was the start time of the contest changed?This is not very friendly to me in China.

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Thank you for adjusting the time

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3 days ago, # |
  Vote: I like it +12 Vote: I do not like it

Sorry for changing the starting time. I've just known that there is a OII contestant who participates online. With the previous starting time, he could access Codeforces and the submissions before the end of the official OII round.

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    3 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    I see.And thanks to reply.

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    3 days ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    I see, no problem. Lucky for me now, as new starting time ensured I would have finished my workday before joining... XD

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

    i think you should make a note on the blog that the time changed, i noticed it only because of a comment, and im sure a lot of people don't go scrolling through comments

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      27 hours ago, # ^ |
        Vote: I like it +12 Vote: I do not like it

      I think there is no need to do another post for it as the contest is postponed,not preponed!

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3 days ago, # |
  Vote: I like it +8 Vote: I do not like it

A div1 after such a long time, but on a weekday afternoon, Have to wait for the next one now :((

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3 days ago, # |
← Rev. 2   Vote: I like it +3 Vote: I do not like it

jeroenodb is so orz

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

hope it will not have any interactive problem :)

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

21:35 UTC+8, great time for me! Really looking forward to this round! Good luck and have fun! :)

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3 days ago, # |
  Vote: I like it 0 Vote: I do not like it

Now the contest is during school, but I will still do it!

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

The rare daytime div2 in China has disappeared …

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2 days ago, # |
← Rev. 2   Vote: I like it +31 Vote: I do not like it

D=F1<E1<F1+F2=E1+E2<F1+F2+F3

I have to say that strategy can play a huge part in this contest for IGM/LGM participants...

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

Looking at the gap between B-C in div 2. I have to mentally ready for hard problem this time.

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41 hour(s) ago, # |
  Vote: I like it 0 Vote: I do not like it

Why did you move the contest to 16:35 utc+3?

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39 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

thank you for moving the time!

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38 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

oink i'm e_x_cited for this.

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36 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

Hope to reach CM :D

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25 hours ago, # |
  Vote: I like it -6 Vote: I do not like it

Christ is King

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18 hours ago, # |
  Vote: I like it -18 Vote: I do not like it

its fine for 1 contest but please dont set this unusual time for future contests too, i barely reach home at that time :(.

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13 hours ago, # |
  Vote: I like it -8 Vote: I do not like it

My local time is 21:35 (UTC+8), which is within my acceptable range. Can you tell me what time it is there?

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

Hi

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7 hours ago, # |
  Vote: I like it -8 Vote: I do not like it

english or spanish

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7 hours ago, # |
  Vote: I like it -15 Vote: I do not like it

Is it safe to assume its a typo that the div 1 score distribution is easier than the div 2?

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    4 hours ago, # ^ |
      Vote: I like it +7 Vote: I do not like it
    1. Scores do not represent absolute difficulties of problems. Only the relative difference (or ratio) within a single round matters.
    2. Div. 1 and Div. 2 are separated, so you get nothing by comparing a problem's score on Div. 1 to a Div. 2's problem.
    3. Therefore, there is nothing wrong with Div. 1 having lower score distribution than Div. 2.
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6 hours ago, # |
  Vote: I like it +14 Vote: I do not like it

As a tester, I tested.

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39 minutes ago, # |
  Vote: I like it 0 Vote: I do not like it

Ugh have to skip this due to change in time. My sleep cycle forces me to sleep at 5-6 these days. Atb everyone

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