10.4.   291

     student   10.2,  -
  ,  . 284.    print ()    
,    .    print_i () -
   ,    .     -
 print_i ().   ,    print_i (), 
    . ,   -
     ().    -
  ,    . , -
  , ,    
 ,    .

    -  . -
  .

  virt_err.cpp

class  {
public:

virtual void foo(int);

virtual void foo(double);

};

class D : public  {
public:

void foo(int) ;

};

int main()
{

D d;

 b, *pb = &d;

b.foo(9); //  foo(int);

b.foo(9.5); //  foo(double);

d.foo(9); // D foo(int);

d.foo(9.5); // D foo(int);

pb -> foo(9); // D foo(int);

pb -> foo (9.5); //  foo(double);

}

-   : : foo ( int) ,  - 
 : : foo (double)    .   d. foo (9 . 5)
    9.5     9.  
 -     d. : : foo (double).

        -
     .   
        . 
    ,      virtual. 
 (private, protected)     .  
 ,    .