/usr/include/CGAL/Optimisation/ is in libcgal-dev 4.5-2.
This file is owned by root:root, with mode 0o755.
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/usr/include/CGAL/Optimisation/Access_coordinates_begin_2.h
/usr/include/CGAL/Optimisation/Access_coordinates_begin_3.h
/usr/include/CGAL/Optimisation/Access_coordinates_begin_d.h
/usr/include/CGAL/Optimisation/Access_dimension_2.h
/usr/include/CGAL/Optimisation/Access_dimension_3.h
/usr/include/CGAL/Optimisation/Access_dimension_d.h
/usr/include/CGAL/Optimisation/Construct_point_2.h
/usr/include/CGAL/Optimisation/Construct_point_3.h
/usr/include/CGAL/Optimisation/Construct_point_d.h
/usr/include/CGAL/Optimisation/assertions.h
/usr/include/CGAL/Optimisation/basic.h
/usr/include/CGAL/Optimisation/debug.h