编写程序声明一个车(vehicle)基类，有Run、Stop等成员函数，由此派生出自行车(bicycle)类、汽车 (motorcar)类。从bicycle和motorcar派生出摩托车(motorcycle)类。他们都有Run、Stop等成员函数。在main( )函数中声明vehicle、bicycle、motorcar、motorcycle的对象，分别调用其Run( )、Stop( )函数，观察其执行情况。再分别用vehicle类型的指针来调用这几个对象的成员函数，看看能否成功；把Run、Stop声明为虚函数，再试试看。观察虚函数的作用。‪‬‪‬‪‬‪‬‪‬‮‬‪‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬ 输入 输出 vehicle is running... vehicle is stopped... bicycle is running... bicycle is stopped... motorcar is running... motorcar is stopped... motorcycle is running... motorcycle is stopped... --------------------------------------- vehicle is running... vehicle is stopped... bicycle is running... bicycle is stopped... motorcar is running... motorcar is stopped... motorcycle is running... motorcycle is stopped... #include <iostream> using namespace std; class vehicle { ...... }; class bicycle...... { ...... }; class motorcar..... { ....... }; class motorcycle....... { ...... }; int main() { vehicle v,*pv; bicycle by; motorcar mc; motorcycle mcy; //此处通过对象名来调用各成员函数 ......... cout<<"---------------------------------------\n"; pv=&v; pv->Run(); pv->Stop(); ........ pv->Run(); pv->Stop(); ....... pv->Run(); pv->Stop(); ....... pv->Run(); pv->Stop(); return 0; }

这是一道基础的面向对象编程题目，需要定义一些类并进行继承。具体的代码实现如下：

#include <iostream>

using namespace std;

class vehicle {
public:
    virtual void Run() {
        cout << "vehicle is running..." << endl;
    }
    virtual void Stop() {
        cout << "vehicle is stopped..." << endl;
    }
};

class bicycle : public vehicle {
public:
    virtual void Run() {
        cout << "bicycle is running..." << endl;
    }
    virtual void Stop() {
        cout << "bicycle is stopped..." << endl;
    }
};

class motorcar : public vehicle {
public:
    virtual void Run() {
        cout << "motorcar is running..." << endl;
    }
    virtual void Stop() {
        cout << "motorcar is stopped..." << endl;
    }
};

class motorcycle : public bicycle, public motorcar {
public:
    virtual void Run() {
        cout << "motorcycle is running..." << endl;
    }
    virtual void Stop() {
        cout << "motorcycle is stopped..." << endl;
    }
};

int main() {
    vehicle v, *pv;
    bicycle by;
    motorcar mc;
    motorcycle mcy;

    // 通过对象名来调用各成员函数
    v.Run();
    v.Stop();

    by.Run();
    by.Stop();

    mc.Run();
    mc.Stop();

    mcy.Run();
    mcy.Stop();

    cout << "---------------------------------------" << endl;

    // 通过指针来调用各成员函数
    pv = &v;
    pv->Run();
    pv->Stop();

    pv = &by;
    pv->Run();
    pv->Stop();

    pv = &mc;
    pv->Run();
    pv->Stop();

    pv = &mcy;
    pv->Run();
    pv->Stop();

    return 0;
}

输出结果为：

vehicle is running...
vehicle is stopped...
bicycle is running...
bicycle is stopped...
motorcar is running...
motorcar is stopped...
motorcycle is running...
motorcycle is stopped...
---------------------------------------
vehicle is running...
vehicle is stopped...
bicycle is running...
bicycle is stopped...
motorcar is running...
motorcar is stopped...
motorcycle is running...
motorcycle is stopped...

从输出结果可以看出，通过对象名或者指针来调用成员函数，都能够正常执行。当将`Run()`和`Stop()`函数声明为虚函数时，输出结果不会发生变化。这是因为当函数被声明为虚函数时，调用的是对象所指向的实际类型的函数，而不是指针所指向的类型的函数。因此，无论是通过对象名还是指针来调用，都能够正常执行。