list_node2 *f5(list_node2 *head, int k) //head-начало списка
{
    list_node2 *curr=head -> next, *last=0, *next;
    int n=0;

    if (k<=0) //Если k<=0 то некорректно задано k
    {
        delete_list2(head);
        return 0;
    }

    while (curr)
    {
        next = curr -> next;
        if (strcmp(curr -> s, curr -> pred -> s)>=0)
        {
            n++;
            if (n==k)
                last=curr;
        }
        else
        {
            if(n>=k)
            {
                last -> pred -> next = curr;
                curr -> pred -> next =0;
                curr -> pred = last -> pred;
                last -> pred =0;
                delete_list2(last);
            }

            n=0;
        }
        curr = next;
    }

    if(n>=k)
            {
                last -> pred -> next = 0;
                last -> pred = 0;
                delete_list2(last);
            }


    return head;
}