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arXiv · 1904.12061

A Linear-Time Algorithm for Radius-Optimally Augmenting Paths in a Metric Space

Christopher Johnson·Haitao Wang
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Abstract

Let $P$ be a path graph of $n$ vertices embedded in a metric space. We consider the problem of adding a new edge to $P$ to minimize the radius of the resulting graph. Previously, a similar problem for minimizing the diameter of the graph was solved in $O(n\log n)$ time. To the best of our knowledge, the problem of minimizing the radius has not been studied before. In this paper, we present an $O(n)$ time algorithm for the problem, which is optimal.

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Christopher Johnson, Haitao Wang. 2019-04-26. A Linear-Time Algorithm for Radius-Optimally Augmenting Paths in a Metric Space. https://arxiv.org/abs/1904.12061

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