P3-decomposition of directed graphs
نویسنده
چکیده
A ~ P3-decomposition of a directed graph D is a partition of the arcs of D into directed paths of length 2. We characterize symmetric digraphs that do not admit a ~ P3-decomposition. We show that the only 2-regular, connected directed graphs that do not admit a ~ P3-decomposition are obtained from undirected odd cycles by replacing each edge by two oppositely directed arcs. In both cases, we give a linear-time algorithm to find a ~ P3-decomposition, if it exists.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 228 شماره
صفحات -
تاریخ انتشار 2017