/in/foo.cc: In function 'int main()':
/in/foo.cc:63:12: error: 'Vector3* Vector3Array::a' is private within this context
   cin >> a.a[i];
            ^
/in/foo.cc:31:11: note: declared private here
  Vector3* a;
           ^
/in/foo.cc:66:5: error: 'Vector3* Vector3Array::a' is private within this context
   a.a[i].Output();
     ^
/in/foo.cc:31:11: note: declared private here
  Vector3* a;
           ^