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Alex_KPR's blog

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

Hi everybody!

The VK Cup is in full action down here!

Zlobober has already given a quick look at the main activity of the guys who got to warm summer St.Petersburg yesterday and checked in the luxurous Courtyard Marriott hotel. Yes, the program is eventful and madly entertaining: yesterday they walked on the rooftops in the heart of the cultural capital of Russia. Today they had lunch on a little ship during a tour along rivers and canals. Besides, the weather has been really good to us!

This time, all the serious events take place opposite the Kazan Cathedral in coworking with VK, in the freedom space. And the morning started with a crazy test round with two spectacular problems, where the first problem was a quiz problem with ten test questions. SobolevTeam achieved a landslide victory. They used a cool idea: according to the Codeforces contest rules, hacks show the contestant's response. The most important thing here is the expected valid result. That's why the team quickly sent and blocked their solution and in the end, didn't submit the problem :P. But their hacks helped them to quickly find the correct responses and then they hacked everybody whose response does not match the correct one. And what do we have in the end? 19 successful hacks!

During the tour the guys had fun reaching for metallic structures of bridges and feasted on tasty food. The most responsible ones studied the rules of the forthcoming CodeGame, thinking through non-trivial strategies. Oh yes, right now the CodeGame Coding phase is in progress!

The guys need to think through the strategy of controlling a battle mage: collect heal and mana potions, cast all sorts of stuff correctly. I love such game-based events as it is a great opportunity to get used to the work place and get our hands working. =)

In the evening, after a small tour around the VK office, the participants will have a TechTalk with the developers and a CodeGame Show that will determine the team with the most effective mage-controlling strategy.

Let's follow the updates on the event together!

 
 
 
 
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5 years ago, # |
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tourist did it again at the last minute :D

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5 years ago, # |
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What about final standings of the final round(not the practice one!)??

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5 years ago, # |
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I read it a few times, but I'm still not sure what was the cool idea used by SobolevTeam. Can someone explain it?

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    5 years ago, # ^ |
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    I'll explain it with an example:

    1. Suppose you're the one hacking.
    2. You see some team answered "A" in question 2.
    3. Hack(Challenge) their solution with question 2 as input.
    4. Success => Answer is not "A"
      Fail => Answer is "A"
    5. You gradually obtain more information to the questions.
    6. Even though your solution might fail, you actually gain much more points with hacking (if you come up with this idea early enough)

    Generally if you're raised in similar environments, you share similar common knowledge.
    If you're stuck on some question, it's highly likely that other contestants are as well.
    So the quickest way to be certain and gain an edge on this is hacking.
    I think this happens to be the case since that almost all contestants are from Russian-speaking countries.

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      5 years ago, # ^ |
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      It kinda makes sense, but at the same time, they have 19 successful hacking attempts and 2 unsuccessful. I don't know if they figured out the answer for questions by randomly hacking.

      Also, how does "hacks show the contestant's response" help? In this problem, it is so obvious what the output will be if you read a code, you don't even need to check what the output was.

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        5 years ago, # ^ |
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        I guess it's a mistake in the original posts: expected answer is shown as well, which is more important. So, that way even if you don't know precise answers for all questions, you can figure them out with (un)sucessful hacks. Afterwards, you can quickly determine if some solution is correct or not.

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5 years ago, # |
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