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arXiv · 1509.00720

Recognizing Weighted Disk Contact Graphs

Boris Klemz·Martin Nöllenburg·Roman Prutkin
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Abstract

Disk contact representations realize graphs by mapping vertices bijectively to interior-disjoint disks in the plane such that two disks touch each other if and only if the corresponding vertices are adjacent in the graph. Deciding whether a vertex-weighted planar graph can be realized such that the disks' radii coincide with the vertex weights is known to be NP-hard. In this work, we reduce the gap between hardness and tractability by analyzing the problem for special graph classes. We show that it remains NP-hard for outerplanar graphs with unit weights and for stars with arbitrary weights, strengthening the previous hardness results. On the positive side, we present constructive linear-time recognition algorithms for caterpillars with unit weights and for embedded stars with arbitrary weights.

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Boris Klemz, Martin Nöllenburg, Roman Prutkin. 2015-09-02. Recognizing Weighted Disk Contact Graphs. https://arxiv.org/abs/1509.00720

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