// For exercise.
// In starting point reproduced from page 851-852 of "The C++ Programming Language", 3ed version.
// With mutual friendship between Outer and Inner classes.
// In this version class Inner is private in class Outer.  Does not compile.

#include <iostream>
#include <string>

class Outer{
private:
  typedef int T;
  int i;

  class Inner{              // Inner is now private in Outer
  friend class Outer;       // Outer is still a friend            
  private:
    int x;
    T y;                    
  public:
    void fi(Outer *p, int v);
  };

  Inner ii;

public:
  int i2;
  static int s;

  int fo(Inner* p);
};

void Outer::Inner::fi(Outer *op, int v){
  op->i = v;                               
  op->i2 = v;
}

int Outer::fo(Inner* ip){
  ii.fi(this,3);
  ip->fi(this,2);
  return ip->x;                            
}

int main(){
  Outer o;  
  Outer::Inner i;           // error:  class Outer::Inner  is private

  i.fi(&o, 5);
}