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arXiv · 1810.07816

The Matching Augmentation Problem: A $\frac74$-Approximation Algorithm

Joe Cheriyan·Jack Dippel·Fabrizio Grandoni·Arindam Khan·Vishnu V. Narayan
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Abstract

We present a $\frac74$ approximation algorithm for the matching augmentation problem (MAP): given a multi-graph with edges of cost either zero or one such that the edges of cost zero form a matching, find a 2-edge connected spanning subgraph (2-ECSS) of minimum cost. We first present a reduction of any given MAP instance to a collection of well-structured MAP instances such that the approximation guarantee is preserved. Then we present a $\frac74$ approximation algorithm for a well-structured MAP instance. The algorithm starts with a min-cost 2-edge cover and then applies ear-augmentation steps. We analyze the cost of the ear-augmentations using an approach similar to the one proposed by Vempala and Vetta for the (unweighted) min-size 2-ECSS problem (`Factor 4/3 approximations for minimum 2-connected subgraphs,' APPROX 2000, LNCS 1913, pp.262-273).

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Joe Cheriyan, Jack Dippel, Fabrizio Grandoni, Arindam Khan, Vishnu V. Narayan. 2018-12-04. The Matching Augmentation Problem: A $\frac74$-Approximation Algorithm. https://doi.org/10.1007/s10107-019-01394-z

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