Atapour, M.; Norouzian, S.; Sheikholeslami, S.M.; Volkmann, L.
(ДЗ"ЛНУ імені Тараса Шевченко", 2017)
Let D = (V, A) be a finite simple directed graph (shortly digraph). A function f : V −→ {−1, 1} is called a twin signed dominating function (TSDF) if f(N −[v]) > 1 and f(N +[v]) > 1 for each vertex v ∈ V . The twin signed ...