c++ - Class interaction tips -

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I'm amazed by some issues while trying to design interactive classes.

Data from class B is either called as an indicator or standard container format, (or even more ambitious, and for STL containers as some shared APTR members) .), My method is to use a function that uses the same arguments and design class B method types according to the arguments? Is there a general rule of thumb to design interacting classes and share data between these classes? Can you please prepare a general plan for some common situations, which usually come into practice (and it is appreciated with some examples)? I think I should read some examples of class interaction in C ++, any signs on this are also appreciated?

There may be a small sample: 

  #include & lt; Iostream & gt; # Include & lt; Vector & gt; #include & lt; Iterator & gt; # Include & lt; Cassert & gt; using namespace std; Class A {public: A (at s, int val): sj (s), val (val), v (new vector & lieutenant; at & g;) {} int fill_hector () {for (int q = 0 ; Kashmir!; + + K) v- & gt; Push_back (val); Return 0; } ~ A () {cout & lt; & Lt; "Dtor is removing the pointer to vector \ n"; Remove V; } Vector & lt; Int & gt; * Get_pointer_to_vector_in_A () {return V; } Private: int sz, val; Of vector & lt; Int & gt; * V; }; Class B {Public: B () {} // Nothing basically does anything print_vector_contents_from_A (vector  * v_from_A) const {(v_from_A-> empty ()); Copy (v_from_A- & gt; Start (), v_from_A- & gt; End (), ostream_iterator  (cout, "\ n")); }}; Int main () {A (10, 4); A.fill_vector (); BB; B.print_vector_contents_from_A (a.get_pointer_to_vector_in_A ()); Return 0; }   
 
 
 It depends on the fact that  A  . If  A  can be validly viewed as a sequence of  int , then I type  size_t (const) and const  and  int & Amp; Operator [] (size_t)  (+ its  const  equivalent) on that. These only make your activities  v.size  and  v []  or  v.at .  
 In  b , you can define  
  static zero B :: print_contents (a const & a) {for ( Size_t i = 0; i & lt; a.size (); I ++) std :: cout & lt; & Lt; A [i] & lt; & Lt; '\ N'; }   
 Any member who has  std :: vector & lt; Int & gt; *  breaks: You can not modify the implementation of  A   std :: vector & lt; Int & gt;  to get away from  get_pointer_to_vector_in_A  works with very unattractive hacks as well as the same words.

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