Josephus::Josephus(int n)
{
Node*p;
first=new Node;
first->num=1;
first->next=first;
for(int i=2;i<=n;i++){
p=new Node;
p->next=first->next;
first->next=p;
p->num=i;
}
}
越新的节点越靠近head总觉的有点奇怪= =