Error_Yuan's blog

By Error_Yuan, history, 4 months ago, In English
  • Problem A~E: The problems themselves are good and typical A~E. Indeed I like problem D. The pretest for A is a bit weak, and it's not a big problem yet.

  • Problem F: The problem has an origin. :) See the link: click. The problem in contest is only a weakened version of the one in Luogu.

  • Problem G: It's said that our great coordinator had not proved the time complexity of the intended solution is correct :) If the authors did, please share it in the editorial. (although this problem is completely beyond my ability :) )

  • Problem H: Oh dear 74TrAkToR, could you please OEIS the sequence before you use the "several-integer-input" problem in rounds next time? Anyone who copied the first example and opened https://oeis.org/A286331 could quickly get the formula. And the problem itself is not so hard imo. Anyway, it should not be used in contest, especially for the last problem.

For me personally, I won't participate in 74TrAkToR rounds any more. The quality of his rounds is far below the average of CF Rounds. This great coordinator has coordinated the following rounds:

  • Codeforces Round 907 (Div. 2), which has a *2000 problem as Div2F :)
  • Codeforces Round 880 (Div. 1 & 2), which got 1400+ downvotes :)
  • Codeforces Round XXX, which has a NP-Hard problem as Div2C with intended solution in O(n log n) :)
  • ... (please take a look at Edit 6)

Dear Mike:

I advise making the round unrated.

You, of course, are shocked. You, of course, think that the round should be rated.

I was also an author of a previous official round. I completely understand the efforts the authors and coordinators paid behind a round. But it is not an excuse to evade responsibility. Serious problems appeared in today's round, in problem F&G&H, ALL OF LAST THREE problems in the contest. According to testers, this round even consists of an unproven problem. If this round remains rated, I guess it will be a decrease in programmers' trust in Codeforces. To avoid this, I kindly advise you to unrate this round and assign at least 2 coordinators for 74TrAkToR rounds in the future.

Please do not reply a "You're wrong, here's why" again!

Edit: I've saved this entry locally to avoid 74TrAkToR from deleting it. 74TrAkToR has done similar things on the announcement of his rounds before. Why can he delete these comments that criticize him?

Edit2: According to testers, the MCS of problem G is wrong, now it is not an unproven problem any more :)

Edit3: I've looked at 74's appeal. Unfortunately, he did not reply to anything that was mentioned in my entry. He just said, "it's all history". :)

Edit4: According to Appeal. 74TrAkToR,

We asked problem H from other authors and, unfortunately, it turned out to be known.

Is it pointing out that 74 knows that H is known, and still use it in the round?

Edit5: I'm sad to see that the rating has been updated. Parhaps I should mention MikeMirzayanov in this blog. Please take a look at this!

Edit6: I've listed all of 74 rounds in 2023. Please check it.

History
  • Vote: I like it
  • +1597
  • Vote: I do not like it

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

agree.

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4 months ago, # |
Rev. 2   Vote: I like it -10 Vote: I do not like it

maybe reply a "You are right,but ..." instead XD

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4 months ago, # |
  Vote: I like it +13 Vote: I do not like it

I would also point out the obviously too small time limit for E. Let's wait for the FST's :) (unless the problem actually just have 20 test cases, which would be pretty weird)

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4 months ago, # |
  Vote: I like it +151 Vote: I do not like it

As you can see...

When there are comments pointing out problems in TheScrasse's round, he realize the problem and feel sorry about it.

When there are comments pointing out problems in 74TrAkToR's round, he just delete it.

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4 months ago, # |
  Vote: I like it +37 Vote: I do not like it

for reference, the NP-hard round

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

agree.

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4 months ago, # |
  Vote: I like it +351 Vote: I do not like it
Me checking codeforces after skipping today's round:
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4 months ago, # |
  Vote: I like it -15 Vote: I do not like it

And problem D is a disaster

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4 months ago, # |
  Vote: I like it +37 Vote: I do not like it

I thought I was the only one who felt 74TrAkToR contests were below average when giving his CF rounds. Glad to see someone else felt that too.

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4 months ago, # |
  Vote: I like it +114 Vote: I do not like it
Spoiler
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4 months ago, # |
  Vote: I like it +8 Vote: I do not like it

I suppose he'll make a better participant than a problem setter lol:)

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4 months ago, # |
  Vote: I like it -16 Vote: I do not like it

Error_Yuan bro why don't you searched the first example of H in oeis.org , you missed the better rank, feeling sad about you bro :(

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

i didn't participate in this round, but i guess thats probably what i'll have to do in future rounds co-ordinated by 74TrAkToR.

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4 months ago, # |
  Vote: I like it -15 Vote: I do not like it

As usual, MikeMirzayanov ignores the community. Typical.

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4 months ago, # |
  Vote: I like it +16 Vote: I do not like it

If this round ends up begin rated in the end this will be so fucking funny. There is no way...

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

I don't see link to this post in the announcement of the round. Was it deleted?)

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

agree.

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

Can't agree more.

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

Can't agree more.

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4 months ago, # |
  Vote: I like it +17 Vote: I do not like it

The repetition of problem H might not be the reason to make the round unrated (as was said before), but the situation of G should be.

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

We asked problem H from other authors and, unfortunately, it turned out to be known.

Apparently yes? https://codeforces.com/blog/entry/124060?#comment-1101227