Elem *next = L->next; 

    Elem

*prev = L->prev; 

    delete

L;              

    prev->next = next;    

    Elem *tmp = L->link; 

    delete L;            

    L = tmp;             

    Elem *tmp = first->next; 

    delete

first;            

    first = tmp;             

    if (first

== NULL)

        last = NULL;         

    else

        first->prev = NULL;  

    Elem *T

= L;

    while

(T->link != L)

        T = T->link;          

    if (T != L)

    {

        Elem

*tmp = L->link;   

        delete

L;             

        L = tmp;              

        T->link = L;          

    }

    else

    {

        delete

L;             

        L = NULL;             

    }

    Elem *tmp = L->link->link;

    delete

L->link;           

    L->link = tmp;