Abstract
The problem of covering minimum cost common bases of two matroids is NP-complete, even if the two matroids coincide, and the costs are all equal to 1. In this paper we show that the following special case is solvable in polynomial time: given a digraph D = (V,A) with a designated root node r ∈ V and arc-costs c:A → ℝ, find a minimum cardinality subset H of the arc set A such that H intersects every minimum c-cost r-arborescence. The algorithm we give solves a weighted version as well, in which a nonnegative weight function w:A → ℝ + is also given, and we want to find a subset H of the arc set such that H intersects every minimum c-cost r-arborescence, and w(H) is minimum. The running time of the algorithm is O(n 3 T(n,m)), where n and m denote the number of nodes and arcs of the input digraph, and T(n,m) is the time needed for a minimum s − t cut computation in this digraph. A polyhedral description is not given, and seems rather challenging.
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References
Bárász, M., Becker, J., Frank, A.: An algorithm for source location in directed graphs. Oper. Res. Lett. 33(3), 221–230 (2005)
Fulkerson, D.R.: Packing rooted directed cuts in a weighted directed graph. Mathematical Programming 6, 1–13 (1974), doi:10.1007/BF01580218
The EGRES Group: Covering minimum cost spanning trees, EGRES QP-2011-08, www.cs.elte.hu/egres
Kamiyama, N.: Robustness of Minimum Cost Arborescences. In: Asano, T., Nakano, S.-I., Okamoto, Y., Watanabe, O. (eds.) ISAAC 2011. LNCS, vol. 7074, pp. 130–139. Springer, Heidelberg (2011)
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Bernáth, A., Pap, G. (2013). Blocking Optimal Arborescences. In: Goemans, M., Correa, J. (eds) Integer Programming and Combinatorial Optimization. IPCO 2013. Lecture Notes in Computer Science, vol 7801. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-36694-9_7
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DOI: https://doi.org/10.1007/978-3-642-36694-9_7
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-36693-2
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