滴滴租车的代码问题

Question

public static void main(String[] args) { car[] cars={new passengerCar("奥迪A6" , 500, 4), new passengerCar("马自达6",400,4), new Pickup("皮卡雪6",450,4,2), new passengerCar("金龙",800,20), new Truck("松花江",400,4), new Truck("依维柯",1000,20) }; 

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cars[i].show(); 这个数组和最后这个car[i].show()还请大神帮忙解释一下