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What is the most optimal solution for this problem ?
By TheCreator, history, 4 months ago, In English

Given a connected undirected graph consisting of N N nodes, determine how many connected components the graph will break into if each node is removed.

For example, consider a graph with the following undirected edges:

1-2, 1-3, 1-4, 4-5, 5-6, 4-6.

If we remove node 1, there will be 3 connected components. If we remove node 2, there will be 1 connected component. If we remove node 3, there will be 1 connected component. If we remove node 4, there will be 2 connected components. If we remove node 5, there will be 1 connected component. If we remove node 6, there will be 1 connected component.

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4 months ago, # |
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Auto comment: topic has been updated by TheCreator (previous revision, new revision, compare).

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4 months ago, # |
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I am wrong, disregard :)

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    4 months ago, # ^ |
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    Actually, you need to count the number of articulation points, not the number of bridges, you can see why by this example:

    1 2

    1 3

    3 2

    2 4

    2 5

    4 5

    here, there isn't any bridge but by removing node 2, there gonna be two connected components

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      4 months ago, # ^ |
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      I don't know how to quickly calculate the number of connected components by removing each articulation point, still thinking about it

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4 months ago, # |
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https://github.com/wery0/CP-library/blob/master/Graphs/Graph/Graph.cpp#L95

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    4 months ago, # ^ |
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    bro has every single graph problems as a callable function in his library, holy shit

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4 months ago, # |
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This problem appeared in a recent Atcoder Beginner Contest, ABC334G: Christmas Color Grid 2 and ExplodingFreeze showed me an elegant way to compute this value.

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