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arXiv · 2311.02708

Highly Connected Steiner Subgraph -- Parameterized Algorithms and Applications to Hitting Set Problems

Eduard Eiben·Diptapriyo Majumdar·M. S. Ramanujan
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Abstract

Given a simple connected undirected graph G = (V, E), a set X \subseteq V(G), and integers k and p, STEINER SUBGRAPH EXTENSION problem asks if there exists a set S \supseteq X with at most k vertices such that G[S] is p-edge-connected. This is a natural generalization of a well-studied problem STEINER TREE (set p=1 and X as the set of all terminals). In this paper, we initiate the study of STEINER SUBGRAPH EXTENSION from the perspective of parameterized complexity and give a fixed-parameter algorithm parameterized by k and p on graphs of bounded degeneracy. In case we remove the assumption of the input graph being bounded degenerate, then the STEINER SUBGRAPH EXTENSION problem becomes W[1]-hard. Besides being an independent advance on the parameterized complexity of network design problems, our result has natural applications. In particular, we use our result to obtain singly exponential-time FPT algorithms for several vertex deletion problem studied in the literature, where the goal is to delete a smallest set of vertices such that (i) the resulting graph belongs to a specific hereditary graph class, and (ii) the deleted set of vertices induces a p-edge-connected subgraph of the input graph.

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Eduard Eiben, Diptapriyo Majumdar, M. S. Ramanujan. 2025-10-03. Highly Connected Steiner Subgraph -- Parameterized Algorithms and Applications to Hitting Set Problems. https://arxiv.org/abs/2311.02708

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