运用图的最优填充分解定理和局部最优填充定理,将一些特殊图类G1×G2,S(G),R(G)和双圈图分解为一些可求得最小填充数的图,得到如下结果:(1)F(Pm×R)≤(m-2)(n-2),其中m≥2,n≥2;(2)若G是有m条边的n阶2-连通图,则F(S(G))=m+F(G);(3)设图G为双圈图,两个诱导圈的圈长分别为P和q,t为这两个圈公共部分的路上的顶点个数(不包括两个端点),NF(G)=P+q-t-6.
By using the decomposition theorem and the local reductive elimination for the fill-in of graphs, the fill-in numbers of some special graphs, such as G1×G2, S(G), R(G) and double cyclic graphs were studied. And the following results were obtained: (1) F(Pm×Pn)≤ (m - 2)(n - 2), wtlere m ≥ 2, n≥ 2; (2) ifG is a 2-connected graph with m edges and n vertices, then F(S(G)) = m + F(G); (3) let G be a double cyclic graph, the length of the two cycles being p and q, respectively, and t the number of the vertices which are both in the two cycles (the end points are excluded), then F(G) = p+ q -t- 6.