摘要
In this note, we denote by G a graph with order n, by V and E the vertex set andedge set of G, respectively. V<sub>0</sub>={v∈V|d(v)≥n/2}, V<sub>0</sub>=V\V<sub>0</sub>. Let H be a subgraph ofG. For simplicity, we also use H to denote the vertex set of it. For a∈V S, TV,