第九周 【项目1-复数类中的运算符重载（续）】

问题描述：

在复数类中的运算符重载基础上
（1）再定义一目运算符 -，-c相当于0-c。
（2）定义Complex类中的<<和>>运算符的重载，实现输入和输出，改造原程序中对运算结果显示方式，使程序读起来更自然。
代码：

#include <iostream>using namespace std;class Complex{public:    Complex(){        real=0;        imag=0;    }    Complex(double r,double i)  {        real=r;        imag=i;    }    friend Complex operator+(Complex &c1, Complex &c2);    friend Complex operator+(double d1, Complex &c2);    friend Complex operator+(Complex &c1, double d2);    friend Complex operator-(Complex &c1, Complex &c2);    friend Complex operator-(double d1, Complex &c2);    friend Complex operator-(Complex &c1, double d2);    friend Complex operator*(Complex &c1, Complex &c2);    friend Complex operator*(double d1, Complex &c2);    friend Complex operator*(Complex &c1, double d2);    friend Complex operator/(Complex &c1, Complex &c2);    friend Complex operator/(double d1, Complex &c2);    friend Complex operator/(Complex &c1, double d2);    Complex operator-();    friend ostream& operator<<(ostream& out,const Complex& c);    friend istream& operator>>(istream& in,Complex& c);    void display();private:    double real;    double imag;};Complex Complex::operator-(){    return(0-*this);}ostream& operator<<(ostream& out,const Complex& c){    out<<"("<<c.real;    if(c.imag>=0) out<<"+";    out<<c.imag<<"i)";    return out;}istream& operator>>(istream& in,Complex& c){    int a,b;    char sign,i;    do{        cout<<"input a complex number(a+bi或a-bi):";        in>>a>>sign>>b>>i;    }    while(!((sign=='+'||sign=='-')&&i=='i'));    c.real=a;    c.imag=(sign=='+')?b:-b;    return in;}Complex operator+(Complex &c1, Complex &c2)  {    Complex c;    c.real=c1.real+c2.real;    c.imag=c1.imag+c2.imag;    return c;}Complex operator+(double d1, Complex &c2)  {    Complex c(d1,0);    return c+c2;}Complex operator+(Complex &c1, double d2){    Complex c(d2,0);    return c1+c;}Complex operator-(Complex &c1, Complex &c2)  {    Complex c;    c.real=c1.real-c2.real;    c.imag=c1.imag-c2.imag;    return c;}Complex operator-(double d1, Complex &c2)  {    Complex c(d1,0);    return c-c2;}Complex operator-(Complex &c1, double d2)  {    Complex c(d2,0);    return c1-c;}Complex 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;}Complex operator*(double d1, Complex &c2)  {    Complex c(d1,0);    return c*c2;}Complex operator*(Complex &c1, double d2){    Complex c(d2,0);    return c1*c;}Complex 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;}Complex operator/(double d1, Complex &c2)  {    Complex c(d1,0);    return c/c2;}Complex operator/(Complex &c1, double d2)  {    Complex c(d2,0);    return c1/c;}void Complex::display()  {    cout<<"("<<real<<","<<imag<<"i)"<<endl;}int main()  {    Complex c1,c2,c3;    double d=11;    cout<<"c1: "<<endl;;    cin>>c1;    cout<<"c2: "<<endl;    cin>>c2;    cout<<"c1="<<c1<<endl;    cout<<"c2="<<c2<<endl;    cout<<"d="<<d<<endl;    c3=c1+c2;    cout<<"c1+c2="<<c3<<endl;    cout<<"c1+d="<<(c1+d)<<endl;    cout<<"d+c1="<<(d+c1)<<endl;    c3=c1-c2;    cout<<"c1-c2="<<c3<<endl;    cout<<"c1-d="<<(c1-d)<<endl;    cout<<"d-c1="<<(d-c1)<<endl;    c3=c1*c2;    cout<<"c1*c2="<<c3<<endl;    cout<<"c1*d="<<(c1*d)<<endl;    cout<<"d*c1="<<(d*c1)<<endl;    c3=c1/c2;    cout<<"c1/c2="<<c3<<endl;    cout<<"c1/d="<<(c1/d)<<endl;    cout<<"d/c1="<<(d/c1)<<endl;    return 0;}

运行结果：