https://codereview.appspot.com/583750043/diff/577780043/lily/skyline.cc File lily/skyline.cc (right):
https://codereview.appspot.com/583750043/diff/577780043/lily/skyline.cc#newcode75 lily/skyline.cc:75: i.print (); I'm sorry, I gave you imperfect advice here because I had an iterator on my mind. Now that I see i.print(), I realize that it should be for (auto &i : b) to guarantee that it uses a reference to the item rather than making a copy of the item. Again, sorry. https://codereview.appspot.com/583750043/
