Finding a Maximum Clique in a Grounded 1-Bend String Graph

التفاصيل البيبلوغرافية
العنوان: Finding a Maximum Clique in a Grounded 1-Bend String Graph
المؤلفون: Keil, J. Mark, Mondal, Debajyoti, Moradi, Ehsan, Nekrich, Yakov
سنة النشر: 2021
المجموعة: Computer Science
مصطلحات موضوعية: Computer Science - Computational Geometry, Computer Science - Computational Complexity, Computer Science - Data Structures and Algorithms, 68Q25, 65D18, I.3.5
الوصف: A grounded 1-bend string graph is an intersection graph of a set of polygonal lines, each with one bend, such that the lines lie above a common horizontal line $\ell$ and have exactly one endpoint on $\ell$. We show that the problem of finding a maximum clique in a grounded 1-bend string graph is APX-hard, even for strictly $y$-monotone strings. For general 1-bend strings, the problem remains APX-hard even if we restrict the position of the bends and end-points to lie on at most three parallel horizontal lines. We give fast algorithms to compute a maximum clique for different subclasses of grounded segment graphs, which are formed by restricting the strings to various forms of $L$-shapes.
Comment: A preliminary version of the paper was presented at the 32nd Canadian Conference on Computational Geometry (CCCG 2020)
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2107.05198
رقم الأكسشن: edsarx.2107.05198
قاعدة البيانات: arXiv