Publications with Elham Havvaei
Parameterized leaf power recognition via embedding into graph products.
D. Eppstein and E. Havvaei.
arXiv:1810.02452.
Proc. 13th International Symposium on Parameterized and Exact Computation (IPEC 2018), Helsinki, Finland, 2018.
Leibniz International Proceedings in Informatics (LIPIcs) 115, 2018, pp. 16:1–16:14.
Algorithmica 82 (8): 2337–2359, 2020 (special issue for IPEC 2018).A leaf power graph is the graph formed from the leaves of a tree by making two leaves adjacent when their tree distance is at most k. We show that recognizing these graphs is fixed-parameter tractable in a combination of two parameters: k and the degeneracy of the graph.
(James Nastos has pointed out a minor error in our statement of known prior results: the figure depicting chordal graphs that are not 4-leaf powers is labeled as a complete set of forbidden subgraphs, but it is only the complete set among graphs without true twin vertices.)
Simplifying activity-on-edge graphs.
D. Eppstein, D. Frishberg, and E. Havvaei.
arXiv:2002.01610.
Proc. 17th Scandinavian Symposium and Workshops on Algorithm Theory (SWAT 2020).
Leibniz International Proceedings in Informatics (LIPIcs) 162, 2020, pp. 24:1–24:14.Given a partially ordered set of activities, we find in polynomial time a directed acyclic graph and a mapping from activities to its edges, such that the sequences of activities along paths in the graph are exactly the totally ordered subsets of activities in the input.
Parameterized complexity of finding subgraphs with hereditary properties on hereditary graph classes.
D. Eppstein, E. Havvaei, and S. Gupta.
arXiv:2101.09918.
Proc. 23rd International Symposium on Fundamentals of Computation Theory, 2021.
Springer, Lecture Notes in Comp. Sci. 12867 (2021), pp. 217–229.We provide a partial classification of the complexity of parameterized graph problems of the form "find a \(k\)-vertex induced subgraph with property \(X\) in a larger subgraph with property \(Y\)", in terms of the existence of large cliques and large independent sets in the graphs with properties \(X\) and \(Y\).