简小的C++基础--重载运算符1

#include <iostream>using namespace std;class Complex{public:    Complex(){real = 0;imag = 0;}    Complex(double r,double i){real = r;imag = i;}    friend Complex operator+(Complex &c1,Complex &c2);    void display();private:    double real;    double imag;};Complex operator+(Complex &c1,Complex &c2){    return Complex(c1.real + c2.real,c1.imag + c2.imag);}void Complex::display(){    cout << "(" << real <<"," << imag << "i)" <<endl;}int main(int argc, char *argv[]){    cout << "Hello World!" << endl;    Complex c1(4,5),c2(1,-12),c3;    c3 = c1 + c2;    cout << "c1 = " ; c1.display();    cout << "c2 = " ; c2.display();    cout << "c3 = " ; c3.display();    return 0;}