On Poset Sandwich Problems
نویسندگان
چکیده
A graph Gs = (V,Es) is a sandwich for a pair of graph Gt = (V,Et) and G = (V,E) if Et ⊆ Es ⊆ E. Any poset, or partially ordered set, admits a unique graph representation which is directed and transitive. In this paper we introduce the notion of sandwich poset problems inspired by former sandwich problems on comparability graphs. In particular, we are interested in seriesparallel and interval posets which are subclasses of 2-dimensional posets, we describe polynomial algorithms for these two classes of poset sandwich problems and then prove that the problem of deciding the existence of a 2-dimensional sandwich poset is NP-complete.
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