2015年第六周项目六：复数模板类（2）_liyingjie01的专栏

</pre><pre name="code" class="cpp">#include <iostream>
using namespace std;

template<class T1>
class Complex
{
public:
    Complex( )
    {
        real=0;
        imag=0;
    }
    Complex(T1 r,T1 i)
    {
        real=r;
        imag=i;
    }
    Complex complex_add(const Complex &c2);  //实现加法的成员函数
    template<class T2> friend Complex<T2> add_complex(const Complex<T2> &c1, const Complex<T2> &c2);   //利用了模板的外部函数要作为友元函数，注意声明方式：类声明中也必须给出模板声明。这一行程序可以在CodeBlocks中调试通过，将T2换成T1，VS2008也接受
    void display( );
private:
    T1 real;
    T1 imag;
};

//成员函数的实现
template<class T1>
Complex<T1> Complex<T1>::complex_add(const Complex<T1> &c2)
{
    Complex<T1> c;
    c.real=real+c2.real;
    c.imag=imag+c2.imag;
    return c;
}

//友元函数的实现
template<class T1>
Complex<T1> add_complex(const Complex<T1> &c1, const Complex<T1> &c2)
{
    Complex<T1> c;
    c.real=c1.real+c2.real;
    c.imag=c1.imag+c2.imag;
    return c;
}

template<class T1>
void Complex<T1>::display( )
{
    cout<<"("<<real<<","<<imag<<"i)"<<endl;
}

int main( )
{
    Complex<int> c1(3,4),c2(5,-10),c3;

    c3=c1.complex_add(c2);  //调用成员函数支持加法运算，有一个形参
    cout<<"c1+c2=";
    c3.display( );

    Complex<double> c4(3.1,4.4),c5(5.34,-10.21),c6;

    c6=c4.complex_add(c5);  //调用成员函数支持加法运算，有一个形参
    cout<<"c4+c5=";
    c6.display( );

    Complex<int> c7;
    c7=add_complex(c1,c2);  //调用友员函数支持加法运算，有两个形参
    cout<<"c1+c2=";
    c7.display( );

    Complex<double> c8;
    c8=add_complex(c4,c5);  //调用友员函数支持加法运算，有两个形参
    cout<<"c4+c5=";
    c8.display( );

    return 0;
}</pre><pre name="code" class="cpp">#include <io