（2）请用类的友元函数，，而不是成员函数，再次完成上面提及的运算符的重载；
/* Copyright (c) 2014, 烟台大学计算机学院 * All rights reserved. * 文件名称：test.cpp * 作者：陈丹妮 * 完成日期：2015年 4 月 29 日 * 版 本 号：v1.0 */#include <iostream>using namespace std;class Complex{public:Complex(double r=0,double i=0):real(r),imag(i){}friend Complex operator+(Complex &c1,Complex &c2);friend Complex operator-(Complex &c1,Complex &c2);friend Complex operator*(Complex &c1,Complex &c2);friend Complex operator/(Complex &c1,Complex &c2);void display();private:double real;double imag;};//下面定义成员函数//复数相加： (a+bi)+(c+di)=(a+c)+(b+d)i.Complex operator+(Complex &c1,Complex &c2){Complex c;c.real=c1.real+c2.real;c.imag=c1.imag+c2.imag;return c;}//复数相减：(a+bi)-(c+di)=(a-c)+(b-d)i.Complex operator-(Complex &c1,Complex &c2){Complex c;c.real=c1.real-c2.real;c.imag=c1.imag-c2.imag;return c;}//复数相乘：(a+bi)(c+di)=(ac－bd)+(bc+ad)iComplex operator*(Complex &c1,Complex &c2){Complex c;c.real=c1.real*c2.real-c1.imag*c2.imag;c.imag=c1.imag*c2.real+c1.real*c2.imag;return c;}//复数相除：(a+bi)/(c+di)=(ac+bd)/(c^2+d^2) +(bc-ad)/(c^2+d^2)iComplex operator/(Complex &c1,Complex &c2){Complex c;c.real=(c1.real*c2.real+c1.imag*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);c.imag=(c1.imag*c2.real-c1.real*c2.imag)/(c2.real*c2.real+c2.imag*c2.imag);return c;}void Complex::display(){cout<<"("<<real<<","<<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=";c1.display();cout<<"c2=";c2.display();c3=c1+c2;cout<<"c1+c2=";c3.display();c3=c1-c2;cout<<"c1-c2=";c3.display();c3=c1*c2;cout<<"c1*c2=";c3.display();c3=c1/c2;cout<<"c1/c2=";c3.display();return 0;}<img src="?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvbnVmYW5nZG9uZ2Rl/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center" alt="" />心得体会：注意在类的成员函数和在类的友元函数是有区别的，形参的形式不同。继续加油！
你让我尝到了每时每刻想你的疼苦，
