Characterizing Extremal Digraphs for Identifying Codes and Extremal Cases of Bondy's Theorem on Induced Subsets
نویسندگان
چکیده
An identifying code of a (di)graph G is a dominating subset C of the vertices of G such that all distinct vertices of G have distinct (in)neighbourhoods within C. In this paper, we classify all finite digraphs which only admit their whole vertex set as an identifying code. We also classify all such infinite oriented graphs. Furthermore, by relating this concept to a well-known theorem of A. Bondy on set systems, we classify the extremal cases for this theorem.
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عنوان ژورنال:
- Graphs and Combinatorics
دوره 29 شماره
صفحات -
تاریخ انتشار 2013