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Beta Round #8 — csacademy.com
By csacademy, 8 years ago, In English

Hello, Codeforces!

We are happy to announce that we're going to host a new contest at csacademy.com. Our Beta Round #8 will take place on Saturday, July/02/2016 16:00 (UTC). If you want to take part in this round you need to register before the contest begins. Just like the previous rounds, this will be a Div1 + Div2. Due to the feedback we've got during the past couple of weeks we decided to change the format, by adding an extra easy problem. So this round will consist of 7 tasks of varied difficulty.

Platform changes since Beta Round #7:

  • We redesigned the homepage. It now includes a global chat, latest blog entries, future contests and top leaderboard.
  • We launched a new lessons section:
  1. Introduction to graphs
  2. Breadth first search
  3. Stack Introduction
  4. Stack Application: Soldiers Row
  • We introduced a new markup language for the chat.
  • We added emoticons to the chat.
  • We added latex to chat.
  • We launched a graph editor tool.
  • We added voting for comments.
  • We added a new user colour.

Contest format:

  • You will have to solve 7 tasks in 2 hours.
  • There will be full feedback throughout the entire contest.
  • Tasks will not have partial scoring, so you need to pass all test cases for a solution to count (ACM-ICPC-style).
  • Tasks will have dynamic scores. According to the number of users that solve a problem the score will vary between 100 and 1000.
  • Besides the score, each user will also get a penalty that is going to be used as a tie breaker.

About the penalty system:

  • Computed using the following formula: the minute of the last accepted solution + the penalty for each solved task. The penalty for a solved task is equal to log2 (no_of_submissions) * 5.
  • Solutions that don't compile or don't pass the example test cases are ignored.
  • Once you solve a task you can still resubmit. All the following solutions will be ignored for both the score and the penalty.

We still recommend using an updated version of Google Chrome. If you find any bugs please email us at [email protected]

Don't forget to like us on Facebook, VK and follow us on Twitter.

EDIT: The ratings have been updated and the editorial has been published.

  • Vote: I like it
  • +156
  • Vote: I do not like it

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8 years ago, # |
← Rev. 2   Vote: I like it +51 Vote: I do not like it

This judge has a lot of potential!

Congratuliations to its dedicated team for all the hard work! I can't wait to take part in the contest!!!

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

Who are the problem setters?

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

    All the problems are created by the CSA team. You can try a virtual contest to get an idea about the difficulty of the contest. IMO this round will be a bit easier, though.

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8 years ago, # |
← Rev. 5   Vote: I like it +18 Vote: I do not like it

Hello, csacademy.com. I want to ask you about registration. Please, tell me why the system wrote me that e-mail is not correct? I write the following e-mail: [email protected]. The system wrote me that it was the wrong email address?

Why that might be?

Please, tell me which mail server this system believe is right.

Please, help me.

I will be very grateful.

With respect, 505alex.

Sorry for my bad English.

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    8 years ago, # ^ |
    ← Rev. 3   Vote: I like it +13 Vote: I do not like it

    Yeah, I have same issues. Not only with gmail account, but also with mail.ru one.

    The Google+ link works fine, but is it really the only way? (Probably along with FB link) I am really used to type my email and password, not really using G+/FB much.

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

    We'll look into it, thanks for reporting.

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

    Sorry for the inconvenience, everything should be working fine now.

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      8 years ago, # ^ |
        Vote: I like it +11 Vote: I do not like it

      Yes, now everything works. Thank you very much!

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

After a contest is over ,you should show the test cases for problems.

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

    We are planning to implement this feature, but it will take some time. Mostly because we want to make sure there will be no bugs that allow the participants to view the tests during a contest.

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

Why was the TL for D so strict (1 second) if intended solution is ? And especially if the server volatility is so high?

I submitted the exact same code multiple times, and on the same test case it showed between 700ms (OK) — 1300ms (TLE). After a few attempts at optimizing, I just gave up and submitted the exact same code several times. I eventually got AC on the 28th attempt...

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

    We're sorry for your troubles, we didn't mean to set the time limit so strict. Our solution passed in ~120ms. There were also many Java users who got AC on their first try.

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

I am unable to link my codeforces profile with my csacademy account.

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

    There seems to be an issue with the Codeforces API. It's probably restricted because of the VK Cup final.

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

Some solutions in problem B used map < string , int > directly to map the string.

What is the complexity of such a solution? Can someone explain?

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    8 years ago, # ^ |
    ← Rev. 2   Vote: I like it +16 Vote: I do not like it

    The height of the red-black tree used for a map is O(log N), so storing a set of strings takes O(sum(lengths) * log N).

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

A feature which tells the difficulty of a task would be nicer. Otherwise ,the platform is really good.

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