VK Cup 2019-2020 — Elimination Round (Engine) and Codeforces Round #623

By PavelKunyavskiy, history, 5 years ago, In English
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5 years ago, # |
  Vote: I like it +194 Vote: I do not like it

Maybe you need to improve your English.

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    5 years ago, # ^ |
    ← Rev. 2   Vote: I like it +6 Vote: I do not like it

    Russian statement and editorial is full of typos and silly mistakes as well, so I think author should either buy a new keyboard or learn to type... (Or maybe stop using google translate)

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5 years ago, # |
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We need codes also!

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5 years ago, # |
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In problem F you may observe that one of primitive roots in nimber field of size $$$2^{2^k}$$$ is $$$2^{2^k}-1$$$ so you may precalculate some of its powers beforehand to further simplify BSGS-algorithm and take discrete logarithm with base being a primitive root. If you do so, you won't need to develop tricky multiplication algorithm as $$$64^2$$$ algo with precalc for powers of two would be enough.

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5 years ago, # |
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Can you give a better explanation for the optimization of problem (A. Recommendations)? I got to the O(n^2) solution during the contest but couldn't improve it.

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5 years ago, # |
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Can you please explain more on how to improve the complexity of A.Recommendations from N^2 to Nlogn.

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    5 years ago, # ^ |
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    I have used heap and greedy approach 71716787

    First i have put all unique elements in a dictionary with list of values.

    Then i keep a temp list to store all the list and pop one largest element to keep in that position and others increase one position and carry on doing this till temp is empty , time complexity — O(N) + N*O(log(N))

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5 years ago, # |
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Can someone tell me why my solution for Div1A/Div2D will TLE? I think its time complexity is nlogn.

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5 years ago, # |
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Can anyone please explain more about the problem 1310B. thanks in advance.

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4 years ago, # |
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Can anyone pls tell me what is wrong with my code? It gives the correct output with my editor. Solution Code: 97113733

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3 years ago, # |
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Problem $$$D$$$ is so cool! My favorite 2300 problem I've ever solved (and I've solved 56 problems of that rating).

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15 months ago, # |
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The tutorial of the problem F seems like Pohlig–Hellman_algorithm.

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