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Cache's blog

By Cache, history, 8 months ago, In English,

Greetings Codeforces Community!

I would like to invite you to participate in CodeChef October Lunchtime 2019. This is a 3-hour contest and everyone is welcome to participate and test their coding skills. And the problems are available in English, Hindi, Bengali, Russian, Mandarin and Vietnamese.

If you have any original and engaging problem ideas, and you’re interested in them being used in the CodeChef's contests, you can share them here: www.codechef.com/problemsetting/new-ideas.

I hope you will join your fellow programmers and enjoy the contest problems. Joining me on the problem setting panel are:

  • Setter and Editorialist: J3far (Jafar Badour)

  • Tester: teja349 (Teja Vardhan Reddy)

  • Statement Verifier: Xellos (Jakub Safin)

  • Mandarin Translator: gediiiiiii (Gedi Zheng)

  • Vietnamese Translator: Team VNOI

  • Russian Translator: Fedosik (Fedor Korobeinikov)

  • Bengali Translator: solaimanope (Mohammad Solaiman)

  • Hindi Translator: Akash Shrivastava

Contest Details:

  • Start Date & Time: 26th October 2019 (1930 hrs) to 26th October 2019 (2230 hrs). (Indian Standard Time — +5:30 GMT) — Check your timezone
  • Contest link: https://www.codechef.com/LTIME77
  • Registration: You just need to have a CodeChef handle to participate. For all those who are interested and do not have a CodeChef handle, are requested to register in order to participate.
  • Prizes: Top 10 Indian and top 10 Global school students from ranklist will receive certificates and CodeChef laddus, with which the winners can claim cool CodeChef goodies. Know more here: https://discuss.codechef.com/t/how-do-i-win-a-codechef-goodie/7344. Good Luck!
    Hope to see you participating!!
    Happy Programming!!
 
 
 
 
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8 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Was div1 really hard or I am too noob :(

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8 months ago, # |
Rev. 2   Vote: I like it +22 Vote: I do not like it

Anyone else thinks kthnumber has a bad model solution? I got AC on the big subtask but WA on the small one with O(N*logN) and O(N^2).

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    8 months ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    Can you please explain your $$$NlogN$$$ solution once?

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      8 months ago, # ^ |
      Rev. 2   Vote: I like it +3 Vote: I do not like it

      make A = sum a[i] * 2^(n-i-1) * x^i * i! and B = sum x^-i / i! for 0 <= i < n, answer for 1 <= i <= n is (A * B)[i-1] / (i-1)!

      If it wasn't clear, those 2 are polynomials so just use fft to multiply them.

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    8 months ago, # ^ |
      Vote: I like it +36 Vote: I do not like it

    Anyone else
    Everyone except authors.

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      8 months ago, # ^ |
        Vote: I like it +5 Vote: I do not like it

      Looks like they fixed the issue now without warning anyone :D

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        8 months ago, # ^ |
          Vote: I like it +31 Vote: I do not like it

        They updated ratings with buggy scoreboard as well.

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

can someone please share the approach for DDQUERY?