An Inverse-Ackermann Style Lower Bound for the Online Minimum Spanning Tree
نویسنده
چکیده
We consider the problem of preprocessing an edgeweighted tree T in order to quickly answer queries of the following type: does a given edge e belong in the minimum spanning tree of T [ feg? Whereas the offline minimum spanning tree verification problem admits a lovely linear time solution, we demonstrate an inherent inverseAckermann type tradeoff in the online MST verification problem. In particular, any scheme that answers queries in t comparisons must invest (n log t(n)) time preprocessing the tree, where t is the inverse of the tth row of Ackermann’s function. This implies a query lower bound of ( (n)) for the case of linear preprocessing time. We also show that our lower bound is tight to within a factor of 2 in the t parameter.
منابع مشابه
An Inverse-Ackermann Style Lower Bound for the Online Minimum Spanning Tree Verification Problem
We consider the problem of preprocessing an edgeweighted tree in order to quickly answer queries of the following type: does a given edge belong in the minimum spanning tree of ? Whereas the offline minimum spanning tree verification problem admits a lovely linear time solution, we demonstrate an inherent inverseAckermann type tradeoff in the online MST verification problem. In particular, any ...
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تاریخ انتشار 2002