The Minimum Latency Problem Is NP-Hard for Weighted Trees

  • René Sitters
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2337)


In the minimum latency problem (MLP) we are given n points v 1,..., v n and a distance d(v i,v j) between any pair of points. We have to find a tour, starting at v 1 and visiting all points, for which the sum of arrival times is minimal. The arrival time at a point v i is the traveled distance from v 1 to v i in the tour. The minimum latency problem is MAX-SNP-hard for general metric spaces, but the complexity for the problem where the metric is given by an edge-weighted tree has been a long-standing open problem. We show that the minimum latency problem is NP-hard for trees even with weights in {0,1}.


Completion Time Travel Salesman Problem Competitive Ratio Total Completion Time Weighted Tree 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • René Sitters
    • 1
  1. 1.Department of Mathematics and Computer ScienceTechnische Universiteit EindhovenEindhovenThe Netherlands

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