Abstract
Let G be a strongly connected directed graph. We consider the following three problems, where we wish to compute the smallest strongly connected spanning subgraph of G that maintains respectively: the 2-edge-connected blocks of G (2EC-B); the 2-edge-connected components of G (2EC-C); both the 2-edge-connected blocks and the 2-edge-connected components of G (2EC-B-C). All three problems are NP-hard, and thus we are interested in efficient approximation algorithms. For 2EC-C we can obtain a 3/2-approximation by combining previously known results. For 2EC-B and 2EC-B-C, we present new 4-approximation algorithms that run in linear time. We also propose various heuristics to improve the size of the computed subgraphs in practice, and conduct a thorough experimental study to assess their merits in practical scenarios.
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Georgiadis, L., Italiano, G.F., Papadopoulos, C., Parotsidis, N. (2015). Approximating the Smallest Spanning Subgraph for 2-Edge-Connectivity in Directed Graphs. In: Bansal, N., Finocchi, I. (eds) Algorithms - ESA 2015. Lecture Notes in Computer Science(), vol 9294. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-48350-3_49
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DOI: https://doi.org/10.1007/978-3-662-48350-3_49
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