gKseni's blog

By gKseni, 8 years ago, In Russian

Мои поздравления всем прошедшим в отборочный этап Яндекс.Алгоритма! :) До начала первого раунда осталось чуть меньше суток! Отборочный этап состоит из трёх раундов:

Продолжительность каждого раунда — 100 минут по правилам TCM/Time.

Напоминаю, что 25 лучших программистов пройдут в финал, где сразятся за денежные призы.

Дерзайте, все получится! :)

  • Vote: I like it
  • +39
  • Vote: I do not like it

»
8 years ago, # |
Rev. 2   Vote: I like it +12 Vote: I do not like it

Notes to self from Yandex.Algorithm team:

  1. Participants this year are super clever, do not underestimate them

  2. Having two relatively easy problems was a good idea

  3. Having over 250 tests in both of them in total was not such good idea

  4. Do not make statements about boys, girls and beds — contestants ask too many clarifications about them

We're super sorry about the testing queue today and make sure that won't happen in further rounds.

Wish us better luck next time. See you on June 10!

  • »
    »
    8 years ago, # ^ |
    Rev. 2   Vote: I like it 0 Vote: I do not like it

    (four, freaking cf parser) I'm not sure if it was intended to be a joke, but the problem is not in boys and girls but in the fact that statement was just wrong

»
8 years ago, # |
  Vote: I like it +39 Vote: I do not like it

What was that? Rejudge? At first I got WA10 for the second submission for C, then I was rewriting the whole solution like for 10 minutes, submitted and now the previous submission somehow changed to OK.

  • »
    »
    8 years ago, # ^ |
    Rev. 3   Vote: I like it +11 Vote: I do not like it

    I had the same situation during contest. Due to it I tried to find a bug instead of solving problem D(((

    UPD. Jury answer: "Тест 10 не соответствовал условию, был заменён и было пересуживание."

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

      And so, why wasn't there any declaration in the system? I really lost a lot of time because of it. Even a slight notification could've helped me with it.

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

        The same story. Lost more that 30 min trying to "fix" my correct solution for C instead of solving D.

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

How to solve D, E?

  • »
    »
    8 years ago, # ^ |
    Rev. 2   Vote: I like it +10 Vote: I do not like it

    D: as a result we have some blocks boy..boy girl..girl boy..boy etc. That means that for each number of these blocks we choose the pairs that bound blocks and then multiply them by number of filling n boys/girls into k places (which is arrangement (n+k-1 choose n))