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arXiv · 2308.16020

Decomposing Triangulations into 4-Connected Components

Sabine Cornelsen·Gregor Diatzko
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Abstract

A connected graph is 4-connected if it contains at least five vertices and removing any three of them does not disconnect it. A frequent preprocessing step in graph drawing is to decompose a plane graph into its 4-connected components and to determine their nesting structure. A linear-time algorithm for this problem was already proposed by Kant. However, using common graph data structures, we found the subroutine dealing with triangulated graphs difficult to implement in such a way that it actually runs in linear time. As a drop-in replacement, we provide a different, easy-to-implement linear-time algorithm that decomposes a triangulated graph into its 4-connected components and computes the respective nesting structure. The algorithm is based on depth-first search.

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Sabine Cornelsen, Gregor Diatzko. 2023-08-30. Decomposing Triangulations into 4-Connected Components. https://arxiv.org/abs/2308.16020

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