share information between 2 classes in different hierarchy

share information between 2 classes in different hierarchy

I'm totally noob, and im studying a design patterns, I want to know which
a more elegant way to share data/variables between 2 objects using c++ or
java or c#
I have a simple class hierarchy, like that
http://s1285.photobucket.com/user/wandersonp/media/share_data_between_2_objects_zpsd9a626d0.jpg.html
for example how can I communicate the Hero object with monster, and
monster to drop_loop object
Thanks
Wanderson