Pushing Vertices and Orienting Edges
نویسنده
چکیده
William F. Klostermeyer Dept. Statistics and Computer Science West Virginia University Morgantown, WV 26506-6330 e-mail: [email protected] ABSTRACT A directed graph operation called pushing a vertex is studied. When a vertex is pushed, the orientation of each of its incident edges is reversed. We consider the problems of pushing vertices so as to produce strongly connected, semi-connected, and acyclic digraphs. NP-completeness results are shown for each problem. It is shown that it is possible to create a directed path between any two vertices in a digraph; additional positive results and characterizations are shown for tournaments, outerplanar digraphs, and Hamiltonian cycles.
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عنوان ژورنال:
- Ars Comb.
دوره 51 شماره
صفحات -
تاریخ انتشار 1999