橋接模式（C++）

#include <iostream>using namespace std;class software{public:    software(){}    virtual ~software(){}    virtual void exec()=0;};class game : public software{public:    game(){}    virtual ~game(){}    void exec(){cout<<"play game"<<endl;}};class office : public software{public:    office(){}    virtual ~office(){}    void exec(){cout<<"work office"<<endl;}};class computer{public:    computer():_instance(NULL){}    virtual ~computer(){}    void setsoftware(software *instance){_instance=instance;}    virtual void Exec()=0;protected:    software *_instance;};class wincomputer : public computer{public:    wincomputer(){}    virtual ~wincomputer(){}    void Exec(){cout<<"win  ";_instance->exec();}};class maccomputer : public computer{public:    maccomputer(){}    virtual ~maccomputer(){}    void Exec(){cout<<"mac  ";_instance->exec();}};int main(){    computer *pc=new wincomputer;    software *ps=new office;    pc->setsoftware(ps);    pc->Exec();    delete ps;    delete pc;    pc=new maccomputer;    ps=new game;    pc->setsoftware(ps);    pc->Exec();    delete ps;    delete pc;    system("pause");    return 0;}