#include<iostream.h>

class complex //複數類宣告

{ public: //外部介面

complex(double r=0.0,double i=0.0) //建構函式

{real=r;imag=i;}

complex operator +(complex &c2); //運算子"+"過載成員函式

complex operator /(int c); //運算子"/"過載成員函式

complex operator =(complex &c2); //運算子"="過載成員函式

void display(); //輸出複數

void get();

private: //私有資料成員

double real; //複數實部

double imag; //複數虛部

};

complex complex::operator +(complex &c2)

{

double r,i;

r=real+c2.real;

i=imag+c2.imag;

return complex(r,i);

}

complex complex::operator /(int c)

{

return complex(real/c,imag/c);

}

/*運算子"="過載成員函式*/

complex complex::operator =(complex &c2)

{

real = c2.real;

imag = c2.imag;

return *this;

}

void complex::display()

{

cout<<"("<<real<<","<<imag<<"i)"<<endl;

}

void complex::get()

{

cin>>real;

cin>>imag;

}

int main()

{

int i;

complex c[3];

for(i=0;i<3;++i)

{

cout<<"輸入第"<<i+1<<"個複數：";

c[i].get();

}

cout<<"和為";

(c[0]+c[1]+c[2]).display();

cout<<"平均值為：";

((c[0]+c[1]+c[2])/3).display();

return 0;

}這是體現C++風格的，你需要簡單的，再追問吧……