Which digraphs are round?
نویسنده
چکیده
A digraph D is round if the vertices of D can be circularly ordered as VI, V2, ... , Vn so that, for each vertex Vi, the out-neighbours of Vi appear consecutively following Vi and the in-neighbours of Vi appear consecutively preceding Vi in the ordering. We characterize round digraphs in terms of forbidden substructures. Our proof implies a polynomial algorithm to decide if a digraph is round.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 19 شماره
صفحات -
تاریخ انتشار 1999