//程序段一：

#include <iostream>

using namespace std;

class Complex
{
    public:
        Complex(int r,int i):real(r),imag(i){}
        Complex operator ++();                                 //    相当于 ++Time ,单操作数运算符的重载 
        Complex operator ++(int);                            //  相当于 Time++ 
        Complex (int r);                                    //    此乃转换构造函数 
//        Complex operator +(Complex &tmp);                    //    使用类的成员函数进行“+”运算符的重载 
        friend Complex operator +(Complex &tmp1,Complex &tmp2);    
        friend ostream& operator<<(ostream& output,Complex& tmp);
        friend istream& operator>>(istream& input,Complex& tmp);
        

    private:
        int real;
        int imag;
};
/*
Complex Complex::operator +(Complex &tmp)
{
    return Complex(this->real + tmp.real,this->imag + tmp.imag);
}
*/
Complex::Complex(int r)                                        
{
    this->real = r;
    this->imag = 0;
}

Complex Complex::operator ++()
{
    this->real = this->real + 1;
    this->imag = this->imag; 
    return *this;
}

Complex Complex::operator ++(int)
{
    this->real = this->real + 1;
    this->imag = this->imag; 
    return *this;
}

istream& operator>>(istream& input,Complex& tmp)         //对输入流的重载 
{
    input>>tmp.real>>tmp.imag;
    return input;
}

Complex operator +(Complex &tmp1,Complex &tmp2)            //使用类的友元函数进行“+”运算符的重载 （注意：友元是类的友元） 
{
    return Complex(tmp1.real + tmp2.real , tmp1.imag + tmp2.imag);
}

ostream& operator<< (ostream& output,Complex& tmp)         //对输出流的重载 
{
    output<<"["<<tmp.real<<"+"<<tmp.imag<<"i"<<"]";
    return output;
}

int main()
{
    int r = 10;
    Complex b(1,2);
    Complex a = 10 + b;  //本应隐示等价于Complex a = Complex(10) + b;
    cout<<a<<endl;
    getchar();
    return 0;
}

问程序段一中main函数内：Complex a = 10 + b;总报错~ 难道编译器不知道将10-》10+0i 再利用运算符重载实现复数加法吗？相反我的程序端二却又可以实现隐示转换，请问他们有什么区别呢？ 谢谢~下面是程序段二

#include <iostream>

using namespace std;

class Complex
{
    public:
        ~Complex(){}
        Complex(int r,int i):real(r),imag(i){}
        Complex(int r){this->real = r;this->imag = 0;}
        operator int(){return real;}
        friend Complex operator + (Complex& tmp1,Complex& tmp2);
        
    private:
        int real;
        int imag;
};    

Complex operator + (Complex& tmp1,Complex& tmp2)
{
    return Complex(tmp1.real + tmp2.real , tmp1.imag + tmp2.imag);
}

int main()
{
    Complex a(1,2);
    Complex c = Complex(10);
    Complex b = a + 10; 
    getchar();
    return 0;
}

之前帮你改掉的那些错误竟然还在，有错不改，每次还问同样的错误有什么意义？！

其它恶心的错误不说了，仅就你提的这个问题，还是 const const const ……
friend Complex operator +(const Complex &tmp1,const Complex &tmp2);
Complex operator +(const Complex &tmp1,const Complex &tmp2)

BTW：既然用C++，却又不按C++规定的做，每每逆向而行，还问为什么

这问题之前还答过一次 https://bbs.bccn.net/thread-457572-1-1.html

谢谢！ 这叫学了又忘，忘了又学！

我加了const但是还是不行~

加了const可以了，谢谢大神！ 我回头总结一下~