The diameter of an interval graph is twice of its radius
نویسندگان
چکیده
In an interval graph G = (V,E) the distance between two vertices u, v is de£ned as the smallest number of edges in a path joining u and v. The eccentricity of a vertex v is the maximum among distances from all other vertices of V . The diameter (δ) and radius (ρ) of the graph G is respectively the maximum and minimum among all the eccentricities of G. The center of the graph G is the set C(G) of vertices with eccentricity ρ. In this context our aim is to establish the relation ρ = ⌈ δ 2 ⌉ for an interval graph and to determine the center of it. Keywords—Interval graph, interval tree, radius, center.
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