300iq's blog

300iq Contest 1
By 300iq, 5 years 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, jqdai0815, 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
  • Vote: I like it
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  • Vote: I do not like it

Comments Comments (10)
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5 years ago, # |
  Vote: I like it +32 Vote: I do not like it

editorial?

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5 years 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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    5 years ago, # ^ |
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    No, any connected component. And it is true, probably you misread the statement.

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      5 years 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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        5 years ago, # ^ |
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        There exists another subset, which violates the constraint.

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

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5 years ago, # |
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Can someone please share the editorial for contest 2?

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5 years ago, # |
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(Problem D, Dates) Please, anybody can explain, what is meant here : (Tutorial)Let’s keep largest indj− psumsrj and smallest indi − psumsli in the vertex of segment tree, now all what you need to do is to check the inversions of these values of two children in each vertex.

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