void bingji(LinkList *L1,LinkList *L2,LinkList *&L3)//
{
    LinkList *p1=L1->next,*p2=L2->next;
    //L3=(LinkList*)malloc(sizeof(LinkList));
    L3=L1;//L3指向L1
   
    while(p1!=NULL)
    {
        while(p2!=NULL&&p2->date<=p1->date)   {
            if(p2->date<p1->date)
            {
                p2->next=L3->next;//向L3中插入p2
                L3->next=p2;
            }
            p2=p2->next;
        }
        p1=p1->next;        
    }
    sort(L3);
}