程式學習日記，如果我幫助了你請讓我知道

#include <iostream>

using namespace std;
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
class Cls1
{
  public:
     Cls1();
     virtual void word();
};

Cls1::Cls1()
{}

void Cls1::word()
{
  cout<<"this function is in Cls1!\n";
}

class Cls2:public Cls1
{
   public:
      Cls2();
      void word();
};

Cls2::Cls2()
{}

void Cls2::word()
{
  cout<<"this function is in Cls2!\n";
}

int main()
{
    
   Cls2 test;
   Cls1 *a;
   a=&test;
   a->word();

return 0;
}