类型适应2.txt

来自「学C++的同学是不是遇到麻烦了」· 文本 代码 · 共 66 行

#include   <iostream.h>
class     A
{
    public:
         A(int  i){a=i;}
         void    print(){cout<<a;}
         int  geta(){return  a;}
     private:
         int   a;
};
class   B:public   A
{
      public:
           B(int  i,int  j):A(i),b(j) { }
           void  print(){A::print();cout<<","<<b<<endl;}
       private:
            int   b;
};
void  fun(A   &d)
{
        cout<<d.geta()*10<<endl;
}
void   main()
{
        B   bb(9,5);
        A   aa(5);
        
        aa=bb;
        bb.print();       9,5       
        aa.print();       9
        cout<<endl;

        A    *pa=new   A(8);
        B    *pb=new   B(1,2);
        pa=pb;
        pb->print();     1,2
        pa->print();     1
        cout<<endl;

       fun(bb);            90

        pb=&bb;
        pb->print();      9,5
        pa=&bb;          
        pa->print();      9
        cout<<endl;
}








9,5
9
1,2
1
90
9,5
9