skylines_[DOWN].print ();
}
+Real
+Skyline_pair::left () const
+{
+ return min (skylines_[UP].left (), skylines_[DOWN].left ());
+}
+
+Real
+Skyline_pair::right () const
+{
+ return max (skylines_[UP].right (), skylines_[DOWN].right ());
+}
+
void
Skyline_pair::print_points () const
{