1   #include <iostream>
 2   using namespace std; 
 3   template <typename T>  
 4      
 5      
 6      class complex 
 7       { 
 8       public: 
 9           complex(T x, T y){m_x=x;m_y=y;}
10      private:
11               T m_x;     T m_y;   
12               friend ostream& operator<<<T>(ostream &s,const complex<T> &t);
13   };
14   
15                    template <typename T> 
16                   ostream & operator<<(ostream &s,const complex<T> &t)
17                    {    s<<t.m_x<<"+"<<t.m_y<<"i";
18                     return s;
19                    }
20               int main()
21               {         complex<double> tt1(1.9, 2.8);     
22                       std::cout << tt1 << endl;     
23                       complex<int> tt2(1, 2);     
24                       std::cout << tt2 << endl;
25               }