1 #include <iostream>
 2
 3 using namespace std;
 4
 5 /*
 6 //1.类模板的函数都写在类的内部
 7 template <typename T>
 8 class Complex
 9 {
10     friend ostream& operator<<(ostream& out,Complex& c)
11     {
12         out<<c.a<<"+"<<c.b<<"i";
13         return out;
14     }
15
16 public:
17     Complex(T a,T b)
18     {
19         this->a=a;
20         this->b=b;
21     }
22
23     Complex operator+(Complex& c)
24     {
25         Complex temp(this->a+c.a,this->b+c.b);
26         return temp;
27     }
28
29     void printCom()
30     {
31         cout<<this->a<<"+"<<this->b<<"i"<<endl;
32     }
33
34 private:
35     T a;
36     T b;
37 };
38 */
39
40 //2.类模板的函数都写在类的外部
41 template <typename T>
42 class Complex
43 {
44     //注意，友元函数在类模板的类体里面声明的时候，在函数的名字和函数参数类型之间加了一个<T>，若不加这个<T>，则编译通不过！
45     friend ostream& operator<<<T>(ostream& out,Complex& c);
46
47 public:
48     Complex(T,T);//构造函数
49     Complex operator+(Complex& );//重载“+”操作符
50     void printCom();//普通函数
51
52 private:
53     T a;
54     T b;
55 };
56
57 //注意友元函数在类体里面的声明的写法！
58 template <typename T>
59 ostream& operator<<(ostream& out,Complex<T>& c)
60 {
61     out<<c.a<<"+"<<c.b<<"i";
62     return out;
63 }
64
65 template <typename T>
66 Complex<T>::Complex(T a,T b)
67 {
68     this->a=a;
69     this->b=b;
70 }
71
72 template <typename T>
73 Complex<T> Complex<T>::operator+(Complex<T>& c)
74 {
75     Complex<T> temp(this->a+c.a,this->b+c.b);
76     return temp;
77 }
78
79 template <typename T>
80 void Complex<T>::printCom()
81 {
82     cout<<this->a<<"+"<<this->b<<"i"<<endl;
83 }
84
85 int main()
86 {
87     Complex<float> c1(1.2,2.5),c2(3.2,5.3);
88
89     c1.printCom();
90     c2.printCom();
91
92     cout<<c1+c2<<endl;
93
94     return 0;
95 }