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arXiv · 2006.00605

A Fast Algorithm for Online k-servers Problem on Trees

Kamil Khadiev·Maxim Yagafarov
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Abstract

We consider online algorithms for the $k$-server problem on trees. There is a $k$-competitive algorithm for this problem, and it is the best competitive ratio. M. Chrobak and L. Larmore provided it. At the same time, the existing implementation has $O(n)$ time complexity for processing a query and $O(n)$ for prepossessing, where $n$ is the number of nodes in a tree. Another implementation of the algorithm has $O(k^2+k\log n)$ time complexity for processing a query and $O(n\log n)$ for prepossessing. We provide a new time-efficient implementation of the algorithm. It has $O(n)$ time complexity for preprocessing and $O\left(k(\log n)^2\right)$ for processing a query.

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Kamil Khadiev, Maxim Yagafarov. 2020-05-31. A Fast Algorithm for Online k-servers Problem on Trees. https://arxiv.org/abs/2006.00605

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