下列程序编译错误,是由于划线处缺少某个语句,该语句是______。 #include<iostream.h> class A private: int numl; public: A( ):numl(0) A(int i):numl(i) ; class B private: int num2; public: B( ):num2(0) B(int i):num2(i) int my_math(A obj1, B obj2); ; int B::my_math(A obj1,B obj2) return(obj1.numl+obj2.num2); void main(void) A objl(4); B obj,obj2(5); cout<<"obj1+obj2:"<<obj.my_math(obj1,obj2);