Title
How To Secure Matchings Against Edge Failures
Abstract
Suppose we are given a bipartite graph that admits a perfect matching and an adversary may delete any edge from the graph with the intention of destroying all perfect matchings. We consider the task of adding a minimum-cost edge-set to the graph such that the adversary never wins. We show that this problem is equivalent to covering a digraph with nontrivial strongly connected components at minimal cost. We provide efficient exact and approximation algorithms for this task. In particular, for the unit-cost problem, we give a log(2) n-factor approximation algorithm and a polynomial-time algorithm for chordal-bipartite graphs. Furthermore, we give a fixed parameter algorithm for the problem parameterized by the treewidth of the input graph. For general nonnegative weights we give tight upper and lower approximation bounds relative to the directed Steiner forest problem. Additionally, we prove a dichotomy theorem characterizing minor-closed graph classes which allow for a polynomial-time algorithm. To obtain our results, we exploit a close relation to the classical strong connectivity augmentation problem as well as directed Steiner problems.
Year
DOI
Venue
2021
10.1137/20M1336229
SIAM JOURNAL ON DISCRETE MATHEMATICS
Keywords
DocType
Volume
matchings, robustness, connectivity augmentation, graph algorithms, treewidth
Journal
35
Issue
ISSN
Citations 
3
0895-4801
0
PageRank 
References 
Authors
0.34
0
3
Name
Order
Citations
PageRank
Felix Hommelsheim100.34
Moritz Mühlenthaler2175.37
Oliver Schaudt39521.74