hmehta's blog

By hmehta, history, 7 years ago, In English

Topcoder SRM 733 is scheduled to start at 12:00 UTC -4, April 14, 2018.

Featured Problem Writer: ltdtl Update: Match Editorials: https://www.topcoder.com/blog/single-round-match-733-editorials/

SRM 733 will give you a chance to move up the ranks to get an automatic qualification to Round 2 of TCO18 Algorithm Track.

You will be able to register for the SRM in the Arena or Applet 4 hours prior to the start of the match. Registration closes 5 minutes before the match begins, so make sure that you are all ready to go.

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You can compete using:

  • Topcoder Web Arena(Beta) — Please watch this video for step by step guide.

  • Topcoder Java Applet — You can refer to this guide here to set up the applet. (Note that those who have Java 8 installed on their machine will see a security issue — You will have to add Topcoder in security exceptions in Java Control Panel. Please refer to the details in the guide here)

All the best!

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

Why don't you tell the problem setter of this match?

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7 years ago, # |
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Reminder: The match begins in 3 hours

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

Thanks for Participating! Here are the Match Editorials https://www.topcoder.com/blog/single-round-match-733-editorials/

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

1000 div1: google [hamiltonian cycle in a tournament graph], or just go directly to [Wikipedia](https://en.wikipedia.org/wiki/Tournament_(graph_theory)).

It's not nice giving problems like "implement something written in the internet" for an online contest... (and yes, I didn't manage to implement it correctly — but this is a different question, problems should be about ideas, not about googling and implementing).

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    7 years ago, # ^ |
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    I don't see algorithm about Hamiltonian cycle on wikipedia.

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      7 years ago, # ^ |
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      It says "build a path, then construct a cycle in a similar manner". It indeed works like this, but not entirely obvious — so either download the paper from the wikipedia references, or (easier) just google and find the exact algorithm, for example.

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        7 years ago, # ^ |
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        Well, it's not same enough. For path you can always add one vertex, in cycle sometimes you need two add two at a time. Here is article in russian :)

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      7 years ago, # ^ |
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      Proof of the fact it always exists (if tournament if strongly connected) is constructive. It can be as is converted to O(N^3) algorithm, and quite easy to O(N^2) or O(N^3/32).

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        7 years ago, # ^ |
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        How to do it in O(n2)?

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          7 years ago, # ^ |
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          Count a lot of numbers of edges between different sets to find good vertex to add in O(n) time. You can check details in my submission.

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    7 years ago, # ^ |
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    Reminded me of this problem!

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    7 years ago, # ^ |
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    This author had the last round too, solutions to div1 medium and hard were found in a book and div1 medium was googlable directly. I'm not very surprised.

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    7 years ago, # ^ |
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    div1 500: google [number of ways to add edges tree] -> first link gives the exact formula https://math.stackexchange.com/questions/640205/numbers-of-ways-k-1-edges-to-be-added-to-k-connected-components-to-make-th

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      7 years ago, # ^ |
      Rev. 2   Vote: I like it +13 Vote: I do not like it

      Wtf? Even in editorial it is mentioned that this is a classic problem and another example of CF problem is provided...

      I just simply didn't expect such a shit so I didn't even think about googling...

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

Feels bad when the last time me passing the system test is like a year ago lol(and it was in div2).

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7 years ago, # |
  Vote: I like it +26 Vote: I do not like it

Div1 250 editorial solution doesn't even pass systest due to precision errors