def get_page_display_string(current, per, total):
    """
    Get the format string x - x of xx
    :param current: current page
    :param per: count per page
    :param total: total count
    :return: str
    """
    return '{start} - {end} of {total}'.format(
        start=((current - 1) * per + 1) if current else 0,
        end=min(total, current * per),
        total=total)