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arXiv · 1004.1437

A note on Johnson, Minkoff and Phillips' algorithm for the Prize-Collecting Steiner Tree Problem

Paulo Feofiloff·Cristina G. Fernandes·Carlos E. Ferreira·Jose Coelho de Pina
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Abstract

The primal-dual scheme has been used to provide approximation algorithms for many problems. Goemans and Williamson gave a (2-1/(n-1))-approximation for the Prize-Collecting Steiner Tree Problem that runs in O(n^3 log n) time. it applies the primal-dual scheme once for each of the n vertices of the graph. Johnson, Minkoff and Phillips proposed a faster implementation of Goemans and Williamson's algorithm. We give a proof that the approximation ratio of this implementation is exactly 2.

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Paulo Feofiloff, Cristina G. Fernandes, Carlos E. Ferreira, Jose Coelho de Pina. 2010-04-08. A note on Johnson, Minkoff and Phillips' algorithm for the Prize-Collecting Steiner Tree Problem. https://arxiv.org/abs/1004.1437

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