class Complex{public:Complex( ){real=0;imag=0;}Complex(double r, double i){real=r;imag=i;}friend Complex operator+= (Complex &, Complex &);private:double real; //实部double imag; //虚部};———————————————————//函数头{c1.real+=c2.real;c1.imag+=c2.imag++;return c1;}