Closest Pair £ EMST
Claim: Closest Pair £ EMST
Proof:
Given the set of input points, form the EMST
We know the EMST is the MST of the compete graph
on the set of input points and we know from Kruskal’s
Algorithm that the shortest edge in the graph is a
member of the MST
Thus we can check each edge of the EMST to find
the shortest; this will tell us the closest pair
Conclusion: EMST requires W(n log n) time
CS409 - Spring 2000
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