c++多态（抽象基类）练习：组装电脑

 将cpu， disk， mem做抽象基类，camputer调用抽象基类，底层的改变不影响camputer类的实现。

#include 
#include 

using namespace std;

class AbsCpu
{
public:

    virtual string cpu() = 0;
};

class AbsDisk
{
public:

    virtual string disk() = 0;
};

class AbsMem
{
public:

    virtual string mem() = 0;
};

class CpuA : public AbsCpu
{
public:

    string cpu()
    {
        return "exe cpu A";
    }
};

class CpuB : public AbsCpu
{
public:

    string cpu()
    {
        return "exe cpu B";
    }
};

class DiskA : public AbsDisk
{
public:

    string disk()
    {
        return "exe disk A";
    }
};

class DiskB : public AbsDisk
{
public:

    string disk()
    {
        return "exe disk B";
    }
};

class MemA : public AbsMem
{
public:

    string mem()
    {
        return "exe mem A";
    }
};

class MemB : public AbsMem
{
public:

    string mem()
    {
        return "exe mem B";
    }
};


class camputer
{
public:

    void exeCpu(AbsCpu *pCpu)
    {
        cout << pCpu->cpu() << endl;
    }

    void exeDisk(AbsDisk * pDisk)
    {
        cout << pDisk->disk() << endl;
    }

    void exeMem(AbsMem *pMem)
    {
        cout << pMem->mem() << endl;
    }
};

int main()
{
    camputer * pCam = new camputer;
    AbsCpu *pCpu = new CpuA;
    AbsDisk *pDisk = new DiskB;
    AbsMem *pMem = new MemA;

    pCam->exeCpu(pCpu);
    pCam->exeDisk(pDisk);
    pCam->exeMem(pMem);

    cout << "第二台电脑" << endl;

    pCpu = new CpuB;
    pDisk = new DiskB;
    pMem = new MemA;

    pCam->exeCpu(pCpu);
    pCam->exeDisk(pDisk);
    pCam->exeMem(pMem);



    return 0;
}

更新一下：

#include 
#include 

using namespace std;

class AbsCpu
{
public:

    virtual void cpu() = 0;
};

class AbsDisk
{
public:

    virtual void disk() = 0;
};

class AbsMem
{
public:

    virtual void mem() = 0;
};

class CpuA : public AbsCpu
{
public:

    void cpu()
    {
        cout << "exe cpu A" << endl;
    }
};

class CpuB : public AbsCpu
{
public:

    void cpu()
    {
        cout << "exe cpu B" << endl;
    }
};

class DiskA : public AbsDisk
{
public:

    void disk()
    {
        cout << "exe disk A" << endl;
    }
};

class DiskB : public AbsDisk
{
public:

    void disk()
    {
        cout << "exe disk B" << endl;
    }
};

class MemA : public AbsMem
{
public:

    void mem()
    {
        cout << "exe mem A" << endl;
    }
};

class MemB : public AbsMem
{
public:

    void mem()
    {
        cout << "exe mem B" << endl;
    }
};


class camputer
{
public:

    camputer(AbsCpu *cpu, AbsDisk *disk, AbsMem *mem) : m_cpu(cpu),m_disk(disk),m_mem(mem)
    {

    }

    void work()
    {
        m_cpu->cpu();
        m_disk->disk();
        m_mem->mem();
    }

    ~camputer()
    {
        cout << "~camputer" << endl;

        delete m_cpu;
        delete m_disk;
        delete m_mem;

        m_cpu = NULL;
        m_disk = NULL;
        m_mem = NULL;
    }
    
private:
    AbsCpu *m_cpu;
    AbsDisk *m_disk;
    AbsMem *m_mem;
};

int main()
{
    AbsCpu *pCpu = new CpuA;
    AbsDisk *pDisk = new DiskB;
    AbsMem *pMem = new MemA;
    camputer * pCam = new camputer(pCpu, pDisk, pMem);
    pCam->work();

    cout << "第二台电脑" << endl;

    pCpu = new CpuB;
    pDisk = new DiskB;
    pMem = new MemA;
    
    pCam = new camputer(pCpu, pDisk, pMem);
    pCam->work();

    return 0;
}