X     X      XX                                                                                  XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX     XX
XX     XX
______X_____X______XX__________________________________________________________________________________XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XX_____XXXX_____XX