operator>>

Functions
template<class Traits , class Dcel >
std::istream &	CGAL::operator>> (std::istream &is, Arrangement_2< Traits, Dcel > &arr)
	Extracts an arrangement from a given input stream using the input format defined by the Arr_text_formatter class - that is, only the basic geometric and topological features of the arrangement are read and no auxiliary data is attached to the Dcel features.
template<class Traits , class Dcel >
std::istream &	CGAL::operator>> (std::istream &is, Arrangement_with_history_2< Traits, Dcel > &arr)
	Extracts an arrangement-with-history from a given input stream using the default input format.