【单选题】一个n个顶点的连通无向图,其边的个数至少为( )
【单选题】It’s a pity that Andrew didn’t want to go to the conference.________ willing to go,we could have paid all his expenses.
【单选题】It’s a pity that he () such a good chance.
【单选题】It’s a pity that he can’t swim .
【单选题】一个n个顶点的连通无向图,其边的个数至少为( )。