The Reversing Number of a Digraph
نویسندگان
چکیده
A minimum reversing set of a digraph is a smallest sized set of arcs which when reversed makes the digraph acyclic. We investigate a related issue: Given an acyclic digraph D, what is the size of a smallest tournataent T which has the arc set of D as a minimum reversing set? We show that such a T always exists and define the reversing number ofan acyclic digraph to be the number of vertices in T minus the number of vertices in D. We also derive bounds and exact values of the reversing number for certain classes of acyclic digraphs.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 60 شماره
صفحات -
تاریخ انتشار 1995