关于c++中运算符的重载

Question

定义复数类型，如何用成员函数或友元函数实现运算符加，减，乘，除的重载问题

Answer 1

给你一个程序，你看看
complex.h
class complex //复数类声明
{
public: //外部接口
complex(double r=0.0,double i=0.0){real=r;imag=i;} //构造函数
complex operator + (complex c2); //+重载为成员函数
complex operator - (complex c2); //-重载为成员函数
void display(); //输出复数
private: //私有数据成员
double real; //复数实部
double imag; //复数虚部
};
complex.cxx
#include"complex.h"
#include"iostream.h"

complex complex::operator +(complex c2) //重载函数实现
{
complex c;
c.real=c2.real+real;
c.imag=c2.imag+imag;
return complex(c.real, c.imag);
}
complex complex::operator -(complex c2) //重载函数实现
{
complex c;
c.real=real-c2.real;
c.imag=imag-c2.imag;
return complex(c.real,c.imag);
}
void complex::display()
{ cout<<"("<<real<<","<<imag<<")"<<endl; }

app.cxx
#include
#include"Complex.h"
using namespace std;
int main() //主函数
{ complex c1(5,4),c2(2,10),c3; //声明复数类的对象
cout<<"c1="; c1.display();
cout<<"c2="; c2.display();
c3=c1-c2; //使用重载运算符完成复数减法
cout<<"c3=c1-c2=";
c3.display();
c3=c1+c2; //使用重载运算符完成复数加法
cout<<"c3=c1+c2=";
c3.display();
return 0;
}