桥接模式（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;
}