[YTU]_2443( C++习题 复数类--重载运算符3+)

题目描述
请编写程序，处理一个复数与一个double数相加的运算，结果存放在一个double型的变量d1中，输出d1的值，再以复数形式输出此值。定义Complex(复数)类，在成员函数中包含重载类型转换运算符: 
operator double() { return real; }

输入
一个复数与一个double数
输出
d1的值和复数形式的此值
样例输入
3 4
2.5
样例输出
d1=5.50
c2=(5.50, 0.00)


#include <iostream>
#include <iomanip>
using namespace std;
class Complex
{
public:
    Complex();
    Complex(double r);
    Complex(double r,double i);
    operator double();
    void display();
private:
    double real;
    double imag;
};
Complex::Complex(){}
Complex::Complex(double r)
{real=r;imag=0;}
Complex::Complex(double r,double i)
{real=r;imag=i;}
Complex::operator double()
{return real;}
void Complex::display()
{
    cout<<'('<<real<<", "<<imag<<")"<<endl;
}
int main()
{
    cout<<setiosflags(ios::fixed);
    cout<<setprecision(2);
    double real,imag;
    cin>>real>>imag;
    Complex c1(real,imag);
    double d1;
    cin>>d1;
    d1=d1+c1;
    cout<<"d1="<<d1<<endl;
    Complex c2=Complex(d1);
    cout<<"c2=";
    c2.display();
    return 0;
}