300iq's blog

By 300iq, 3 months ago, In English,

Hello everyone, this winter at Petrozavodsk was my first ICPC contest, now it is loaded on the gym.

Contest link.

Virtual participation link.

To ensure Codeforces traditions, I will say thanks to the testers TLE, whzzt, sunset, wxhtxdy, isaf27. Also thanks to izban with help in tasks choosing.

And of course, thanks to MikeMirzayanov for Codeforces and Polygon platforms and help with loading this contest to the gym.

A, Short editorial
B, Short editorial
C, Short editorial
D, Short editorial
E, Short editorial
F, Short editorial
G, Short editorial
H, Short editorial
I, Short editorial
J, Short editorial
K, Short editorial
 
 
 
 
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6 weeks ago, # |
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editorial?

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    6 weeks ago, # ^ |
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      6 weeks ago, # ^ |
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      most of the students in China can't visit *.google.com
      so could you please provide another one in other dropboxs like onedrive?
      thanks a lot ^_^

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4 weeks ago, # |
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For I do you mean to say that for any biconnected component has size at most 6 because otherwise the result is wrong for a tree of 7 vertices?

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    4 weeks ago, # ^ |
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    No, any connected component. And it is true, probably you misread the statement.

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      4 weeks ago, # ^ |
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      So if I have a tree on 7 vertices + 1 additional isolated vertex and I set A=set of vertices of the tree. Then, there does not exist a,b in A such that any path from a to b pass through the isolated vertex?

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        4 weeks ago, # ^ |
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        There exists another subset, which violates the constraint.

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6 days ago, # |
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Can someone explain the solution for problem D with Hall's Theorem? Didn't get in the tutorial.