AlexSkidanov's blog

JavaBlitz Beta Round
By AlexSkidanov, history, 7 years ago, In English

UPDATE: the contest is over, the problems are available for upsolving. If you participated, please tell us how usable and responsive the interface was, and whether everything went well.

Hi, Everybody!

We would like to invite you all to help us test a new competitive programming platform called JavaBlitz.

JavaBlitz rounds are short (up to 2hr 30m) contests with ACM ICPC rules with the only difference that the penalty for an incorrect submission is 4 minutes instead of 20.

The platform only supports Java as the programming language, and, similar to TopCoder, requires participants to implement a method in the given class that receives the input as arguments and returns the result. There's no reading from- and writing to files.

The beta round will take place today, June 8th, at 20:30 Moscow Time / 17:30 UTC / 10:30 AM PDT.

The Beta Round will be 1hr 40min long and will feature three problems. No Div1 D/E level problems will be featured on this round.

The platform is located here: http://javablitz.com, and besides the coming Beta Round has two warmup problems to play around with the arena.

The probability of the system going down during the contest is very high, keep it in mind if you participate :)

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  • Vote: I do not like it

Comments Comments (12)
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7 years ago, # |
  Vote: I like it +8 Vote: I do not like it

Even with my poor Java skills, I would've given it a go — but unfortunately it coincides with CS Academy's Round 32 :(

Best of luck with your platform!

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    7 years ago, # ^ |
    ← Rev. 3   Vote: I like it +16 Vote: I do not like it

    Ah, didn't notice. Thanks for pointing it out.

    I will just push our round back by 1hr 30min, to 17:30 UTC.

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7 years ago, # |
← Rev. 2   Vote: I like it +15 Vote: I do not like it

Is it fine that warmup problems don't include restrictions on variables?

Also, is it that hard to make customizable height to problem statement panel? I think that it can be a hard time to anyone to read long statements in panel of 10 lines height.

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

    I clarified in the second problem that the number of starships is positive. Other than that the restrictions are encoded in the datatypes of the input variables (in particular, in the second problem A naturally doesn't exceed 2^32-1).

    I will try to add the splitter before the contests starts, but can't promise :)

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

Can we have easier problems please.

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

    Yes, the next Beta round will have more problems, including some easier ones.

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

How to solve C?

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

    The resulting point is either

    1. The starting point (you can shoot them right away)
    2. One of the vertices of the squares or a projection of the starting point to one of the sides (you fly to one of the ships and shoot from there the other)
    3. A projection of the starting point to a line that connects two vertices of two different squares.

    Then you enumerate all such points and choose the closest one from which you can actually shoot both cruisers.

    To verify that just cast a ray from the point to all vertices of one square and check if they intersect the other.

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

No lags, сonvenient and intuitive interface, interesting problems ;)

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

Thanks for the contest! I liked the problems. The interface is nice but I didn't like the test/submit popup. When testing, I could either see testcases + correct answers (in problem statement) or my answers. I didn't find a way to see both. It's also not possible to restore deleted (sample) testcase. Also, the submit popup window is unnecessarily big. Still the biggest obstacle is that I don't know Java, but that's my own problem :)

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

    Hi, thanks for feedback!

    The correct answers for the samples in the run window will be there by the next round. I thought we already had them :)

    Regarding the test cases -- the easy way to restore a sample case is to refresh the window and reopen the problem :) I guess the bigger problem is that the custom test cases will get lost in this case. But I think I have a good solution for it, will also implement it before the next round.

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6 years ago, # |
  Vote: I like it +71 Vote: I do not like it

Also, since this popped up, no problems from this particular javablitz test round are part of CBR #488.

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