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shortest single cycle in an unweighted graph n<=1e6

By duongquanghai08, history, 4 months ago, In English

shortest single cycle in an unweighted graph n<=1e6

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4 months ago, # |
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Is it a directed or an undirected graph?

If it's an undirected graph, you can construct a DFS Tree, and every back-edge defines a cycle

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    4 months ago, # ^ |
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    Shortest cycle length here $$$= 3$$$, not defined by only one back edge

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4 months ago, # |
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I think this can help you

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4 months ago, # |
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orz dequy hai

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4 months ago, # |
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It can't be solved in better than $$$O(nm)$$$, where $$$m$$$ is the number of edges.

https://en.m.wikipedia.org/wiki/Girth_(graph_theory)#Computation

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3 months ago, # |
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i can help u, ib for the perfect solution

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