用C++写一个程序包含1.类的定义，构造函数，成员函数 2．两个复数运算的运算符重载.重载 +、-、*、/、++、--、<<、>>等运算符 3. double型数可以转换成复数

好的，以下是一个符合您要求的 C++ 程序示例：

#include <iostream>
using namespace std;

class Complex {
private:
    double real;  // 复数的实部
    double imag;  // 复数的虚部

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

    // 成员函数
    double getReal() const { return real; }
    double getImag() const { return imag; }
    void setReal(double r) { real = r; }
    void setImag(double i) { imag = i; }

    // 运算符重载
    Complex operator+(const Complex& c) const { return Complex(real + c.real, imag + c.imag); }
    Complex operator-(const Complex& c) const { return Complex(real - c.real, imag - c.imag); }
    Complex operator*(const Complex& c) const { return Complex(real * c.real - imag * c.imag, real * c.imag + imag * c.real); }
    Complex operator/(const Complex& c) const {
        double denominator = c.real * c.real + c.imag * c.imag;
        return Complex((real * c.real + imag * c.imag) / denominator, (imag * c.real - real * c.imag) / denominator);
    }
    Complex operator++() { return Complex(++real, ++imag); }
    Complex operator++(int) { return Complex(real++, imag++); }
    Complex operator--() { return Complex(--real, --imag); }
    Complex operator--(int) { return Complex(real--, imag--); }

    friend ostream& operator<<(ostream& os, const Complex& c);
    friend istream& operator>>(istream& is, Complex& c);
};

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

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

// 将 double 类型转换成复数类型
inline Complex doubleToComplex(double x) {
    return Complex(x, 0);
}

int main() {
    Complex c1(1, 2), c2(3, 4);
    cout << "c1 = " << c1 << endl;
    cout << "c2 = " << c2 << endl;

    cout << "c1 + c2 = " << c1 + c2 << endl;
    cout << "c1 - c2 = " << c1 - c2 << endl;
    cout << "c1 * c2 = " << c1 * c2 << endl;
    cout << "c1 / c2 = " << c1 / c2 << endl;

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

    double d = 5.6;
    Complex c3 = doubleToComplex(d);
    cout << "c3 = " << c3 << endl;

    return 0;
}

该程序中，`Complex` 类表示复数，包含实部和虚部两个成员变量，以及相应的构造函数和成员函数。该类还重载了加减乘除、自增自减、输入输出运算符，并提供了将 `double` 类型转换成 `Complex` 类型的函数。在 `main` 函数中，我们创建了两个复数对象 `c1` 和 `c2`，并进行了加减乘除以及自增自减等操作。同时，我们还将一个 `double` 类型的变量转换成了一个复数对象 `c3`。