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arXiv · 1104.2230

Subexponential Parameterized Algorithm for Minimum Fill-in

Fedor V. Fomin·Yngve Villanger
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Abstract

The Minimum Fill-in problem is to decide if a graph can be triangulated by adding at most k edges. Kaplan, Shamir, and Tarjan [FOCS 1994] have shown that the problem is solvable in time O(2^(O(k)) + k2 * nm) on graphs with n vertices and m edges and thus is fixed parameter tractable. Here, we give the first subexponential parameterized algorithm solving Minimum Fill-in in time O(2^(O(\sqrt{k} log k)) + k2 * nm). This substantially lower the complexity of the problem. Techniques developed for Minimum Fill-in can be used to obtain subexponential parameterized algorithms for several related problems including Minimum Chain Completion, Chordal Graph Sandwich, and Triangulating Colored Graph.

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Fedor V. Fomin, Yngve Villanger. 2011-04-12. Subexponential Parameterized Algorithm for Minimum Fill-in. https://arxiv.org/abs/1104.2230

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