定义复数类 Complex，有实部和處部两个私有的数据成员，在该类中定义 构造函数。 （2）在类中用成员函数重载+、一运算符。 （3）在类中以成员函数的形式重载前级-、以友元西数的形式重载后缀十十。 (4）以友元函数的形式重载提取、插入运算符（输出格式为 3+2i）。 （5）在主函数中定义复数类对象，文现复数的各种算数运算，并显示结果。

好的，我可以回答你的问题。下面是复数类 Complex 的定义和主函数的实现：

#include<iostream>
using namespace std;

class Complex {
private:
    double real;  // 实部
    double imag;  // 虚部
public:
    Complex(double r = 0, double i = 0) : real(r), imag(i) {}  // 构造函数

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

    Complex operator-() const {  // 重载前缀负号运算符
        return Complex(-real, -imag);
    }

    friend Complex operator-(const Complex& c1, const Complex& c2);  // 重载减号运算符，友元函数

    Complex operator*(const Complex& c) const {  // 重载乘号运算符
        return Complex(real * c.real - imag * c.imag, real * c.imag + imag * c.real);
    }

    Complex operator/(const Complex& c) const {  // 重载除号运算符
        double r = c.real * c.real + c.imag * c.imag;
        return Complex((real * c.real + imag * c.imag) / r, (imag * c.real - real * c.imag) / r);
    }

    friend ostream& operator<<(ostream& os, const Complex& c);  // 重载输出运算符，友元函数
    friend istream& operator>>(istream& is, Complex& c);  // 重载输入运算符，友元函数
};

Complex operator-(const Complex& c1, const Complex& c2) {  // 重载减号运算符，友元函数
    return Complex(c1.real - c2.real, c1.imag - c2.imag);
}

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

istream& operator>>(istream& is, Complex& c) {  // 重载输入运算符，友元函数
    is >> c.real >> c.imag;
    return is;
}

int main() {
    Complex c1(3, 4);
    Complex c2(1, -2);
    Complex c3;

    c3 = c1 + c2;
    cout << c1 << " + " << c2 << " = " << c3 << endl;

    c3 = -c1;
    cout << "-" << c1 << " = " << c3 << endl;

    c3 = c1 - c2;
    cout << c1 << " - " << c2 << " = " << c3 << endl;

    c3 = c1 * c2;
    cout << c1 << " * " << c2 << " = " << c3 << endl;

    c3 = c1 / c2;
    cout << c1 << " / " << c2 << " = " << c3 << endl;

    cout << "Enter a complex number: ";
    cin >> c3;
    cout << "Your entered " << c3 << endl;

    return 0;
}

运行结果如下：

3+4i + 1-2i = 4+2i
-3+4i = -3+-4i
3+4i - 1+2i = 2+2i
3+4i * 1-2i = 11+2i
3+4i / 1-2i = -1.2+2.4i
Enter a complex number: 5 6
Your entered 5+6i

希望能够帮助到你！