Abstract
The k-median problem is a classical facility location problem. We consider the k-median problem for directed trees, motivated by the problem of locating proxies on the World Wide Web. The two main results of the paper are an O(n log n) time algorithm for k=2 and an O(n log2 n) time algorithm for k=3. The previously known upper bounds for these two cases were O(n 2).
Research supported by grant EPSRC GR/N09077 (UK). M.Chrobak was also partially supported by by NSF grant CCR-9988360. W.Rytter was also partially supported by grant KBN 8T11C03915.
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Chrobak, M., Larmore, L.L., Rytter, W. (2001). The k-Median Problem for Directed Trees. In: Sgall, J., Pultr, A., Kolman, P. (eds) Mathematical Foundations of Computer Science 2001. MFCS 2001. Lecture Notes in Computer Science, vol 2136. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-44683-4_23
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DOI: https://doi.org/10.1007/3-540-44683-4_23
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