bool isPalindrome(CharLinkD * head, CharLinkD * tail) {
        bool answer = true;

        while(head->next != tail->prev || head->next == tail || tail->prev == head)
        {
                if(head->c == tail->c)
                {
                        head = head->next;
                        tail = tail->prev;
                }

                else return false;
        }

        return answer;
}