We have unweighted undirected graph with n vertices and m edges (n < 1e5, m < 1e6). You need to find sum of d(u, v) over all pairs of u v, where d(u, v) — minimal distance between u and v.
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We have unweighted undirected graph with n vertices and m edges (n < 1e5, m < 1e6). You need to find sum of d(u, v) over all pairs of u v, where d(u, v) — minimal distance between u and v.
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I have a certain problem in a previous contest in mind, almost exactly same with this problem, only difference being the constraints for $$$m$$$. Can you please state the source of this problem?
It was on a Belarusian National Olympiad in 2009...
Okay, the problem I was thinking of was "Distance Sum", NERC 2018. The problem was authored by tourist, so he should be able to help better than I can. Good luck on solving the problem.