A linear algorithm for the pos/neg-weighted 1-median problem on a cactus

Computing - Tập 60 - Trang 193-215 - 1998
R. E. Burkard1, J. Krarup2
1Institut für Mathematik, Technische Universität Graz, Graz, Austria
2Department of Computer Science, University of Copenhagen, Copenhagen, Denmark

Tóm tắt

The 1-median problem on a network asks for a vertex minimizing the sum of the weighted shortest path distances from itself to all other vertices, each associated with a certain positive weight. We allow fornegative weights as well and devise an exact algorithm for the resulting ‘pos/neg-weighted’ problem defined on a cactus. The algorithm visits every vertex just once and runs thus in linear time.

Tài liệu tham khảo

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