#include<iostream>using namespace std;class CDemo{ private: int n; public: CDemo(int i=0):n(i){} CDemo operator++();// ++d 成员函数 CDemo operator++(int);// d== operator int(){ return n;}///强制类型转换 int get_n(){ return n; } friend CDemo operator--(CDemo &t);// 全局函数 friend CDemo operator--( CDemo &t,int );};CDemo CDemo::operator++(){ n++; return *this;}CDemo CDemo::operator++(int){ CDemo tmp(*this); n++; return tmp;}CDemo operator--( CDemo &d ){ d.n--; return d;}CDemo operator--( CDemo &d, int ){ CDemo temp(d); d.n--; return temp; } int main(){ CDemo d(5); cout<<(d--)<<endl; d++; cout<<(++d)<<endl; ++d; return 0;}