hmehta's blog

TCO21 Round 1A
By hmehta, history, 4 years ago, In English

The first Online Round of the 2021 Topcoder Open Algorithm Competition has arrived! Round 1A will be held on Saturday April 17, 2021 at 12:00 UTC -4 and you are invited to compete.

How many will qualify?
The 750 highest scorers from each Round 1 will win a spot in Round 2 of the Algorithm Competition.

How to Compete?
Please note that you must register for this round in the Arena or Applet. 

Registration is open for the round and closes at 11:55 UTC -4. Be sure you register early to guarantee your spot in the round as registration is limited to the first 2,500 competitors. Please take a look at our How to Compete guide to understand Topcoder Algorithm rounds better.

Don't forget! There will be one more Round 1 — Round 1B on Wednesday, April 28, 2021 at 07:00 UTC -4.

New to Topcoder and the TCO21? The Algorithm Competition is one of the most fierce and popular tournaments. Battle up against some of the biggest names in coding. Learn more.

The Topcoder Open Algorithm Competition consists of an Onsite Finals and there are three ways to advance to the Onsite Finals:

  • Four online stages,
  • Four online rounds,
  • Up to five onsite regional rounds followed by one online wild card round.

TCO21 Algorithm Competition Schedule:
Round 1A: April 17 at 12:00
Round 1B: April 28 at 07:00
Round 2A: May 22 at 12:00
Round 2B: June 2 at 07:00 
Round 3: July 8 at 07:00
Round 4: July 31 at 12:00

All times are in UTC -4.

Some Important Links:: Match Results (match results, rating changes, challenges, individual test case results), Problem Archive, Problem Writing, Algorithm Rankings, Editorials and Older Editorials(SRM 710 and before),

Best of luck to you in the Arena!
- The Topcoder Community Team

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Comments Comments (31)
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4 years ago, # |
← Rev. 2   Vote: I like it +2 Vote: I do not like it

Update: We are facing some issues setting up the Parallel Round for the members who got a bye or who qualified to Round 4 from Online Stages.

I will update here as soon as it is fixed.

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

    The parallel round is now fixed :)

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4 years ago, # |
  Vote: I like it -27 Vote: I do not like it

we don't get editorials after the contest then what the meaning of doing topcoder

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

    Hey, We generally share the draft of the editorials right at the end of the contest in the arena. It takes a day or two to be published here: https://www.topcoder.com/?s=Editorials. Sorry if you were not able to locate them. Feel free to ask on the blog here incase yo are not able to locate them. Will make sure we put the link here as well after the round.

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

"""Don't forget! There will be one more Round 1 — Round 1B on Wednesday, April 8, 2021 at 07:00 UTC -4."""

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

    If you remove your glasses you will notice the correct time in bottom. Why you are trolling him like that ?

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

      """Consistency is the key to success."""
      Add glasses and read the whole blog once. Use ctrl+F if required to find potential issues in this blog.

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

      Fixed :) Thanks for the catch

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

If I got an automatic berth but lose rating and drop out of the top 250 in Parallel Round 1A, do I have to compete in 1B to qualify for round 2?

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

    On this page
    """Automatic Berths – The 250 members who have the highest Algorithm competition rating as of April 12, 2021 12:00 UTC -4, and who meet all of the following criteria will receive an automatic berth into Online Round 2:"""

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

Is arena giving timeout only to me while logging in?

hmehta can you please check this problem

I for sure have no internet problem (speed is around 16mbps)

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    4 years ago, # ^ |
    ← Rev. 2   Vote: I like it +25 Vote: I do not like it

    Now I am getting JRE doesn't support AES-128, login not allowed

    Did just around 900 registrants broke the shit out of TC? :P

    Now I understand why people say TC sucks..

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

    I'm having the same issue, i initially thought it was something from my end..

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

      Hey, Everyone, Arena is down at the moment and team is working to bring it back up. Will share an update here as soon as it is back up.

      https://discussions.topcoder.com/discussion/5533/tco21-round-1a

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

        Arena is back up! Sorry for the issues!

        All the best for the round!

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

          hmehta is there any criteria that we have to solve at least one problem or anything??

          As there are around 800 registrants and many registrants will not compete, so how top 750 will be decided?

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

        Seems to be working now.

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

Am I the only one having troubles with Arena right now?

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4 years ago, # |
  Vote: I like it +33 Vote: I do not like it

I know its a Round 1, but isn't the 1000 still a bit too standard.

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

    It was brought to our attention that it is (apparently) a famous problem. Neither I nor the testers knew about that (and I actually tried searching for a similar problem). Apparently I'm bad at searching. I'm really sorry about that :(

    Disclaimer: I'm the problem set author.

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

      Out of curiosity: how many testers did you have?

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

    Do you have any links to similar problems?

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

      I still haven't found it :shrug: As I mentioned — I'm apparently bad at searching. But judging by the number of solutions I suppose it is, indeed, famous enough.

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        4 years ago, # ^ |
        ← Rev. 3   Vote: I like it +30 Vote: I do not like it

        Its not exactly that this exact problem is standard. Its just that if you've studied the basics of flows / matching, the flow network is really easy to construct. This was my 4th or 5th ever flows problem, and most of the time taken was due to trying to figure out how to recover flow edges in the template I was using.

        Like this feels somewhat similar to the problems discussed in https://www.topcoder.com/thrive/articles/Maximum%20Flow:%20Part%20Two.

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          4 years ago, # ^ |
            Vote: I like it +68 Vote: I do not like it

          Those who copy-pasted atcoder library max flow which has a built-in function to recover flow edges had to debug C++17(on atcoder) -> C++11 (Topcoder) issues.

          To @admins Upgrade it. It's 2021.

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

            Yeah, its really annoying when C++14 and C++17 specific features don't work on TopCoder, and its the only major competitive coding platform that is still stuck on C++11.

            Not as bad as your case, but its was still annoying to have to replace auto type deducing greater<>() with greater<int>().

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

      https://infoarena.ro/problema/teroristi

      Here's one from the National Olympiad in Informatics in 2010. Though you need to do flow to get 100, create 26 * 26 nodes for the possible paper pieces.

      (The input is:

      First string is the message, then the paper pices, 2 chars for each face. The output is for each letter of the message what piece of paper do you use)

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4 years ago, # |
← Rev. 2   Vote: I like it +11 Vote: I do not like it

Thanks, everyone for competing! :)

Here's the editorial draft: https://docs.google.com/document/d/e/2PACX-1vRmAn_S0dpU8jygJfXwRRyaCItuQhq9_R_fG7qYAMKhVVnN4ELerqyRzFORd9dCyaaM0QcLxzHiK1sQ/pub

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4 years ago, # |
  Vote: I like it +42 Vote: I do not like it

SO SO SOOOO waiting for C++17.

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