The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this pa...
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael ...
We present the first thorough theoretical analysis of the Transitivity Editing problem on digraphs. Herein, the task is to perform a minimum number of arc insertions or deletions ...
Mathias Weller, Christian Komusiewicz, Rolf Nieder...
Let (x, y) be a bivariate polynomial with complex coefficients. The zeroes of (x, y) are given a combinatorial structure by considering them as arcs of a directed graph G(). This p...
The upward planarity testing problem consists of testing if a digraph admits a drawing Γ such that all edges in Γ are monotonically increasing in the vertical direction and no e...
Motivated by issues in machine learning and statistical pattern classification, we investigate a class cover problem (CCP) with an associated family of directed graphs--class cove...