Removing monsters in a map

[ays297]

I have a DB Room and there's a time when player just wants the room to be clean when they enter.

How can I remove all the mobs in a db room when there are no players for 30 minutes.

[Skorm]

@ays297

prontera,100,100,5	script	gold_room_timer	-1,500,500,{
	end;

OnTouch: // On touch reset the timer...
	initnpctimer;
	end;

OnTimer1800000: // On 30 minutes remove monsters if the map is empty & restart timer.
	if(getmapusers(.map_name$) <= 0) {
		killmonsterall .map_name$;
		cleanmap .map_name$;
	}
	initnpctimer;
	end;

OnInit: // On server start the timer...
	.map_name$ = strnpcinfo(4);
	initnpctimer;
	end;
}