Definition 4: These edges are called multiple edges if they incident with the same two vertices. The graph is called multigraph. The graph is called a simple graph, if any two vertices in the graph, may connect at most one edge (i.e, one edge or no edge) and the graph has no loop. The complete graph on n vertices, denoted by Kn, is the simple graph that contains exactly one edge between each pair of distinct vertices❖ Definition 4 ： These edges are called multiple edges if they incident with the same two vertices. The graph is called multigraph. The graph is called a simple graph, if any two vertices in the graph, may connect at most one edge (i.e., one edge or no edge) and the graph has no loop. The complete graph on n vertices, denoted by Kn , is the simple graph that contains exactly one edge between each pair of distinct vertices