请完成Complex类的定义，使得下面的主函数能正常运行。 int main( ) { Complex c1(1,2); cout<<"c1="<<c1; //operator<<(cout,c1); Complex c2(2); // default argument is i=0 cout<<"c2="<<c2<<endl; Complex c3(c1); //invoke the copy constructor cout<<"c3="<<c3; c1=c1+c2+c3; // c1=(c1.operator+(c2)).operator+(c3); cout<<"c1=c1+c2+c3="<<c1; c2=-c3; // c2=c3.operator-(); cout<<"c2=-c3="<<c2; c3=c2-c1; // c3=c2.operator-(c1); cout<<"c3=c2-c1="<< c3; Complex r2=2+c2; // calls operator+ (2, c2) cout<<"r2=2+c2="<<r2; Complex c4; cin>>c4; cout<<"c4="<<c4; cout<<"the module of c4 is: "<<c4.GetMagnitude()<<endl;//计算复数的模 return 0; }

#include <iostream>
#include <cmath>

using namespace std;

class Complex {
private:
    double real; // 实部
    double imag; // 虚部

public:
    // 构造函数
    Complex(double r = 0, double i = 0) : real(r), imag(i) {}

    // 拷贝构造函数
    Complex(const Complex& c) {
        real = c.real;
        imag = c.imag;
    }

    // 重载运算符 +
    Complex operator+(const Complex& c) const {
        return Complex(real + c.real, imag + c.imag);
    }

    // 重载运算符 -
    Complex operator-(const Complex& c) const {
        return Complex(real - c.real, imag - c.imag);
    }

    // 重载运算符 - （负号）
    Complex operator-() const {
        return Complex(-real, -imag);
    }

    // 重载运算符 + （用于实数与复数相加）
    friend Complex operator+(double r, const Complex& c) {
        return Complex(r + c.real, c.imag);
    }

    // 重载运算符 << （输出运算符）
    friend ostream& operator<<(ostream& os, const Complex& c) {
        os << c.real << "+" << c.imag << "i";
        return os;
    }

    // 重载运算符 >> （输入运算符）
    friend istream& operator>>(istream& is, Complex& c) {
        cout << "请输入实部和虚部（以空格分隔）：";
        is >> c.real >> c.imag;
        return is;
    }

    // 计算复数的模
    double GetMagnitude() const {
        return sqrt(real * real + imag * imag);
    }
};

int main() {
    Complex c1(1, 2);
    cout << "c1=" << c1 << endl;
    Complex c2(2);
    cout << "c2=" << c2 << endl;
    Complex c3(c1);
    cout << "c3=" << c3 << endl;
    c1 = c1 + c2 + c3;
    cout << "c1=c1+c2+c3=" << c1 << endl;
    c2 = -c3;
    cout << "c2=-c3=" << c2 << endl;
    c3 = c2 - c1;
    cout << "c3=c2-c1=" << c3 << endl;
    Complex r2 = 2 + c2;
    cout << "r2=2+c2=" << r2 << endl;
    Complex c4;
    cin >> c4;
    cout << "c4=" << c4;
    cout << "the module of c4 is: " << c4.GetMagnitude() << endl;
    return 0;
}