2013/09/23 by Marie Albenque, Albenque, Marie, Kolja Knauer +1
Computer Science · #05C62 #05C85 #Advanced Graph Theory Research #Combinatorics (math.CO) #Computational Geometry and Mesh Generation #Constraint Satisfaction and Optimization #Discrete Mathematics (cs.DM) #FOS: Computer and information sciences #FOS: Mathematics
paper · doi:10.48550/arxiv.1309.5724
openalex publication_date 2013/09/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We prove that the combinatorial optimization problem of determining the hull number of a partial cube is NP-complete. This makes partial cubes the minimal graph class for which NP-completeness of this problem is known and improves some earlier results in the literature. On the other hand we provide a polynomial-time algorithm to determine the hull number of planar partial cube quadrangulations. Instances of the hull number problem for partial cubes described include poset dimension and hitting sets for interiors of curves in the plane. To obtain the above results, we investigate convexity in partial cubes and characterize these graphs in terms of their lattice of convex subgraphs, improving a theorem of Handa. Furthermore we provide a topological representation theorem for planar partial cubes, generalizing a result of Fukuda and Handa about rank three oriented matroids.