第八周项目1-2利用友元函数实现运算符重载

/*Copyright (c) 2011, 烟台大学计算机学院* All rights reserved.* 作    者： 石尧* 完成日期：2014 年04  月 15日* 版 本 号：v1.0** 问题描述：利用友元函数实现运算符重载。* 样例输入：略.* 样例输出：略。* 问题分析：略。*/#include<iostream>using namespace std;class Complex{public:    Complex(){real=0;imag=0;}    Complex(double r,double i){real=r; imag=i;}    Complex operator+(Complex &c2);    Complex operator-(Complex &c2);    Complex operator*(Complex &c2);    Complex operator/(Complex &c2);    friend void display(Complex &);private:    double real;    double imag;};//下面定义成员函数 Complex Complex::operator+(Complex &c2)//定义复数相加函数  {      Complex c;      c.real=real+c2.real;      c.imag=imag+c2.imag;      return c;  }  Complex Complex::operator-(Complex &c2)  {      Complex c;      c.real=real-c2.real;      c.imag=imag-c2.imag;      return c;  }  Complex Complex::operator*(Complex &c2)  {      Complex c;      c.real=real*c2.real;      c.imag=imag*c2.imag;      return c;  }Complex Complex::operator/(Complex &c2)  {      Complex c;      c.real=real/c2.real;      c.imag=imag/c2.imag;      return c;  } void display(Complex &c) {     cout<<"("<<c.real<<","<<c.imag<<"i)"<<endl; }//下面定义用于测试的main()函数int main(){    Complex c1(3,4),c2(5,-10),c3;    cout<<"c1=";    display(c1);    cout<<"c2=";    display(c2);    c3=c1+c2;    cout<<"c1+c2=";    display(c3);    c3=c1-c2;    cout<<"c1-c2=";    display(c3);    c3=c1*c2;    cout<<"c1*c2=";    display(c3);    c3=c1/c2;    cout<<"c1/c2=";    display(c3);    return 0;}心得体会：友元函数在调用时要将引用的数写在括弧内例如：display(c1)，还有声明时不要忘记引用号&。