/usr/include/mdds/ is in libmdds-dev 0.11.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/mdds/compat/
/usr/include/mdds/compat/unique_ptr.hpp
/usr/include/mdds/default_deleter.hpp
/usr/include/mdds/flat_segment_tree.hpp
/usr/include/mdds/flat_segment_tree_def.inl
/usr/include/mdds/flat_segment_tree_itr.hpp
/usr/include/mdds/global.hpp
/usr/include/mdds/hash_container/
/usr/include/mdds/hash_container/map.hpp
/usr/include/mdds/mixed_type_matrix.hpp
/usr/include/mdds/mixed_type_matrix_def.inl
/usr/include/mdds/mixed_type_matrix_element.hpp
/usr/include/mdds/mixed_type_matrix_flag_storage.hpp
/usr/include/mdds/mixed_type_matrix_storage.hpp
/usr/include/mdds/mixed_type_matrix_storage_filled_linear.inl
/usr/include/mdds/mixed_type_matrix_storage_sparse.inl
/usr/include/mdds/multi_type_matrix.hpp
/usr/include/mdds/multi_type_matrix_def.inl
/usr/include/mdds/multi_type_vector.hpp
/usr/include/mdds/multi_type_vector_custom_func1.hpp
/usr/include/mdds/multi_type_vector_custom_func2.hpp
/usr/include/mdds/multi_type_vector_custom_func3.hpp
/usr/include/mdds/multi_type_vector_def.inl
/usr/include/mdds/multi_type_vector_itr.hpp
/usr/include/mdds/multi_type_vector_macro.hpp
/usr/include/mdds/multi_type_vector_trait.hpp
/usr/include/mdds/multi_type_vector_types.hpp
/usr/include/mdds/node.hpp
/usr/include/mdds/point_quad_tree.hpp
/usr/include/mdds/quad_node.hpp
/usr/include/mdds/rectangle_set.hpp
/usr/include/mdds/rectangle_set_def.inl
/usr/include/mdds/segment_tree.hpp
/usr/include/mdds/sorted_string_map.hpp
/usr/include/mdds/sorted_string_map_def.inl