20 [lib.utilities]
	<utility>
		namespace rel_ops { operators !=, >, <=, >= }
		struct pair;
		pair binary operators { operators ==, <, !=, >, >=, <= }
	<functional>
		// function objects, or objects with operator() defined
	<memory>
		template<T> class allocator;
		template<> class allocator<void>;
		template<OutI, T> class raw_storage_iterator;
		temporary buffers
		specialized algorithms for uninitialized_{copy, fill, fill_n}
		template<T> class auto_ptr;
	<ctime>
	<cstdlib>
	<cstring>

21 [lib.strings]
	<string>
		template<T> struct char_traits
		template<> struct char_traits<char>
		template<> struct char_traits<wchar_t>
		template<C, T=c_t<T>, A=a<T> > class basic_string;

		typedef basic_string<char> string;
		typedef basic_string<wchar_t> wstring;
		
		template<C, T, A> void swap(string&, string&)
		template<C, T, A> istream& operator>>(istream&, string&);
		template<C, T, A> istream& getline(istream&, string&, C);
		template<C, T, A> istream& getline(istream&, string&);
		template<C, T, A> ostream& operator<<(ostream&, string&);
	<cctype>
	<cwctype>
	<cstring>
	<cwchar>
	<cstdlib>

23 [lib.containers]
	<deque>
	<list>
	<queue>
	<stack>
	<vector>
	<map>
	<set>
	<bitset>

24 [lib.iterators]
	<iterator>

25 [lib.algorithms]
	<algorithm>
		non-modifying sequence operations 
			for_each, find, find_if, find_end, find_first_of, 
			adjacent_find, count, count_if, mismatch, equal, 
			search, search_n
		modifying sequence operations
			copy, copy_backward, swap, swap_ranges, iter_swap, 
			transform, replace, replace_if, replace_copy,
			replace_copy_if, fill, fill_n, generate, generate_n, 
			remove, remove_if, remove_copy, remove_copy_if, unique,
			unique_copy, reverse, reverse_copy, rotate, 
			rotate_copy, random_shuffle
		sorting and related operations
			sort, stable_sort, partial_sort, partial_sort_copy, 
			nth_element, lower_bound, upper_bound, equal_range, 
			binary_search, merge, inplace_merge, includes, 
			set_union, set_intersection, set_difference, 
			set_symmetric_difference, push_heap, pop_heap, 
			make_heap, sort_heap, min, max, min_element, 
			max_element, lexicographical_compare, next_permutation,
			prev_permutation
	<cstdlib>









