private void doubleSize() {
		if (corridors.length == 0) {
			corridors = new Corridor[2];
			return;
		}
		Corridor[] newVersionOfCorridors = new Corridor[corridors.length*2];
		
		for (int i=0; i<corridors.length; i++) {
			newVersionOfCorridors[i] = corridors[i];
		}
		
		corridors = newVersionOfCorridors;
	}