第一題

#include <iostream>
using namespace std;
class Complex
 {public:
   Complex(){real=0;imag=0;}
   Complex(double r,double i){real=r;imag=i;}
   double get_real();
   double get_imag();
   void display();
  private:
   double real;
   double imag;
 };


double Complex::get_real()
{return real;}


double Complex::get_imag()
{return imag;}


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


Complex operator + (Complex &c1,Complex &c2)
{
 return Complex(c1.get_real()+c2.get_real(),c1.get_imag()+c2.get_imag());
}


int main()
{Complex c1(3,4),c2(5,-10),c3;
 c3=c1+c2;
 cout<<"c3=";
 c3.display();
 return 0;
}