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#2
Arcticanimal2007-09-15 16:58
// forward declaration
class BOAT; class CAR; int TOTALWEIGHT(BOAT boat, CAR car); class BOAT { public: BOAT():WEIGHT(0){} //...... private: int WEIGHT; friend int TOTALWEIGHT(BOAT boat, CAR car); }; class CAR { public: CAR():WEIGHT(0){} //...... private: int WEIGHT; friend int TOTALWEIGHT(BOAT boat, CAR car); }; int TOTALWEIGHT(BOAT boat, CAR car) { return boat.WEIGHT + car.WEIGHT; } 极其简单的语法问题, 闲来无聊就帮你写了  |
定义BOAT与CAR两个类，两者都有WEIGHT属性，定义两者的一个友元函数TOTALWEIGHT（），计算两者的重量和。这个友元函数应该怎么编写，希望提供源程序。