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arXiv · 1903.02161

An Efficient Algorithm for Enumerating Chordal Bipartite Induced Subgraphs in Sparse Graphs

Kazuhiro Kurita·Kunihiro Wasa·Hiroki Arimura·Takeaki Uno
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Abstract

In this paper, we propose a characterization of chordal bipartite graphs and an efficient enumeration algorithm for chordal bipartite induced subgraphs. A chordal bipartite graph is a bipartite graph without induced cycles with length six or more. It is known that the incident graph of a hypergraph is chordal bipartite graph if and only if the hypergraph is $\beta$-acyclic. As the main result of our paper, we show that a graph $G$ is chordal bipartite if and only if there is a special vertex elimination ordering for $G$, called CBEO. Moreover, we propose an algorithm ECB which enumerates all chordal bipartite induced subgraphs in $O(kt\Delta^2)$ time per solution on average, where $k$ is the degeneracy, $t$ is the maximum size of $K_{t,t}$ as an induced subgraph, and $\Delta$ is the degree. ECB achieves constant amortized time enumeration for bounded degree graphs.

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Kazuhiro Kurita, Kunihiro Wasa, Hiroki Arimura, Takeaki Uno. 2019-03-06. An Efficient Algorithm for Enumerating Chordal Bipartite Induced Subgraphs in Sparse Graphs. https://doi.org/10.1007/978-3-030-25005-8_28

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