在双向循环链表中,在p所指的结点之后插入s指针所指的结点,其操作是( )。
①
p->next=s; s->prior=p; p->next->prior=s; s->next=p->next;
②
s->prior=p; s->next=p->next; p->next=s; p->next->prior=s;
③
p->next=s; p->next->prior=s; s->prior=p; s->next=p->next;
④
s->prior=p; s->next=p->next; p->next->prior=s; p->next=s;