MikeMirzayanov's blog

By MikeMirzayanov, 5 years ago, translation, In English,

It is not visible from user point of view, but we've introduced some changes in Codeforces backend to improve system performance. And now we want to test the system before Round 278.

I invite you to take part in Testing Round #11. It will start soon, on November, 20 21:30:00 (UTC). It will be unofficial unrated round.

Pretests are unusually weak to trigger more hack.

If you see any unexpected behavior or bugs, please inform us via comments.

Thanks.

UPD.: Thank you for participation.

Announcement of Testing Round #11
Announcement of Testing Round #11
 
 
 
 
  • Vote: I like it
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5 years ago, # |
  Vote: I like it -35 Vote: I do not like it

Why unofficial unrated?? Which kind of testing??

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

hope the new system do well for coming contests.

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

Sounds good! 2:30 local time ! Maybe I will sleep and get up and sleep again after contest :)

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

"Pretests are unusually weak to trigger more hack."

This made me much happy :D

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5 years ago, # |
  Vote: I like it +6 Vote: I do not like it

How many questions ?!

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

I love this contest

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5 years ago, # |
  Vote: I like it +6 Vote: I do not like it

Start time of this testing round makes me happy) It assures me that I'm not alone with my principle — "Do it in last 24 hours".

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

Statement is not available. problem B

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

When I tried to open problem B, I saw this :

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

in 32 min after beginning of the contest: in the score table problem A score is 418 and in standings when i solved it i got 386 .. !!

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

Glad to see system test is much faster than before!

Edit: Hacks page is gone? Here is link

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    5 years ago, # ^ |
      Vote: I like it +16 Vote: I do not like it

    the number of contestants is too small so you can't determine if it really faster or not

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5 years ago, # |
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How to solve B? I thought of maximum bipartite matching. But was unable to implement

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5 years ago, # |
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I figured out how to generate hacks in java. Was problem for moment because I did not realize that Random random = new Random(); had to be Random random = new Random(200); for instance with specific seed, so that it would be deterministic. Then I had many happy hacks! Can't wait to generate hacks in rated contests! Thanks Mike!

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

i think there is something wrong with system test

My solution for problem B must be Wrong Answer test 25 but it gives Accepted

see test case 25:

http://codeforces.com/contest/491/submission/8769437

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

As above commentator says I see same thing for my submission, number 8769288. For test 5 I have wrong answer, and yet it says ok PANIC! jury answer is not optimal: contestant has 110, jury has 97. However it is other way around, my answer is not optimal, the jury one is!

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    5 years ago, # ^ |
      Vote: I like it +12 Vote: I do not like it

    There was actually a problem with the checker for this task. Now it is fixed.

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

Seems like there's a problem with the Checker of problem B

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

how can i solve the B number problem

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

How to solve C?

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5 years ago, # |
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Who the hell is mehmed_77??? And how he solved all 3 Problems in 1 minute?

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    5 years ago, # ^ |
    Rev. 3   Vote: I like it 0 Vote: I do not like it

    And I noticed a bug, while posting this comment and clicked preview.

    Mike, look please.

    Full size image

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    5 years ago, # ^ |
    Rev. 2   Vote: I like it +3 Vote: I do not like it

    He participated in virtual Contest. First he solved all problems and then Enter virtual contest room and then submit one by one.

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      5 years ago, # ^ |
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      Oh, snap! Haven't noticed that)

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    4 years ago, # ^ |
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    That '#' show that he was in a Virtual contest and certainly he had solved all 3 Problems before start Virtual

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

Hi. Somebody can explain the algorithm of the problem B??? Why substract y to x?? x[i]=x+y;
y[i]=x-y;///WHY??