In generally ,we can say that anytime u redefine an overloading function name from the base class,all of the other versions are automatically hidden in the new class.

• 总结为：继承类把基类的重载函数重定义后，只能调用继承类对象的已重定义的函数，而不是调用基类的那些重载函数（同名函数），即在继承类中基类的重载函数被隐藏！