LinkList *Union(LinkList *D,LinkList *H,LinkList *L)
{
    LinkList *pd,*ph,*pl;
    L=(LinkList *)malloc(sizeof(LinkList));
    pl=L->next;
    pd=D->next;
    ph=H->next;
    while(pd&&ph)
    {
        if(pd->data<ph->data)
        {
            pl->next=pd;
            pd=pd->next;
            pl=pl->next;
        }
        if(pd->data=ph->data)
        {
            pl->next=pd;
            pd=pd->next;
            ph=ph->next;
            pl=pl->next;
        }
        else
        {
            pl->next=ph;
            ph=ph->next;
            pl=pl->next;
        }  
    }
    while(pd!=NULL)
        pl->next=pd;
    while(ph!=NULL)
        pl->next=ph;
}   

LinkList *Inter(LinkList *D,LinkList *H,LinkList *L)
{
    LinkList *pl,*pd,ph;
    L=(LinkList *)malloc(sizeof(LinkList));
    pd=D->next;
    ph=H->next;
    pl=L->next;
    while(pd!=NULL)
    {
        while(ph!=NULL)
        {
        if(pd->data==ph->data)
        {
            pl->next=pd;
            pd=pd->next;
            ph=ph->next;
            pl=pl->next;
        }
        else   
            ph=ph->next;
        }   
        pd=pd->next;
    }
}

LinkList *Differ(LinkList *D,LinkList *H,LinkList *L)
{
    LinkList *pl,*pd,*ph;
    int i=0
    L=(LinkList *)malloc(sizeof(LinkList));
    pd=D->next;
    ph=H->next;
    pl=L->next;
    while(pd!=NULL)
    {
        while(ph!=NULL)
        {
        if(pd->data==ph->data)
        {
            pd=pd->next;
            ph=ph->next;
            i++;
        }
        else
            ph=ph->next;
        }   
        if(i=0)
        {
            pl->next=pd;
            pl=pl->next;
            pd=pd->next;
        }
        pd=pd->next;
    }
}