重载流插入运算符

 1 #include <iostream>
 2 
 3 /* run this program using the console pauser or add your own getch, system("pause") or input loop */
 4 using namespace std;
 5 class Complex
 6 {
 7     public:
 8         Complex(){
 9             real=0;
10             imag=0;
11         }
12         Complex(double r,double i){
13             real=r;
14             imag=i;
15         }
16         Complex operator +(Complex &c2);
17         friend ostream&operator<<(ostream&,Complex&);
18     private:
19         double real;
20         double imag;
21  } ;
22  
23  Complex Complex::operator +(Complex &c2)
24  {
25      return Complex(real+c2.real,imag+c2.imag);
26  }
27  
28  ostream&operator<<(ostream&output,Complex&c)
29  {
30      output<<"("<<c.real<<"+"<<c.imag<<"i)"<<endl;
31      return output;
32  }
33  
34 int main(int argc, char** argv) {
35     Complex c1(2,4),c2(6,10),c3;
36     c3=c1+c2;
37     cout<<c3;
38     return 0;
39 }