Revert "[libcxx][gardening] Move all algorithms into their own headers."
This reverts commit 7ed7d4ccb8991e2b5b95334b508f8cec2faee737 as it
uncovered a Clang bug PR50592.
NOKEYCHECK=True
GitOrigin-RevId: 692d7166f7715514d0ff8090e5bd66668432b270
diff --git a/include/algorithm b/include/algorithm
index 00b6c18..1ae84f7 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -646,93 +646,18 @@
*/
#include <__config>
-#include <__debug>
#include <__bits> // __libcpp_clz
#include <cstddef>
#include <cstring>
#include <functional>
#include <initializer_list>
-#include <utility> // needed to provide swap_ranges.
-#include <memory>
#include <iterator>
#include <memory>
#include <type_traits>
#include <utility> // swap_ranges
#include <version>
-#include <__algorithm/adjacent_find.h>
-#include <__algorithm/all_of.h>
-#include <__algorithm/any_of.h>
-#include <__algorithm/binary_search.h>
-#include <__algorithm/clamp.h>
-#include <__algorithm/comp.h>
-#include <__algorithm/comp_ref_type.h>
-#include <__algorithm/copy.h>
-#include <__algorithm/count.h>
-#include <__algorithm/count_if.h>
-#include <__algorithm/equal.h>
-#include <__algorithm/equal_range.h>
-#include <__algorithm/fill.h>
-#include <__algorithm/find.h>
-#include <__algorithm/find_end.h>
-#include <__algorithm/find_first_of.h>
-#include <__algorithm/find_if.h>
-#include <__algorithm/find_if_not.h>
-#include <__algorithm/for_each.h>
-#include <__algorithm/for_each_n.h>
-#include <__algorithm/generate.h>
-#include <__algorithm/half_positive.h>
-#include <__algorithm/includes.h>
-#include <__algorithm/inplace_merge.h>
-#include <__algorithm/is_heap.h>
-#include <__algorithm/is_heap_until.h>
-#include <__algorithm/is_partitioned.h>
-#include <__algorithm/is_permutation.h>
-#include <__algorithm/is_sorted.h>
-#include <__algorithm/lexicographical_compare.h>
-#include <__algorithm/lower_bound.h>
-#include <__algorithm/make_heap.h>
-#include <__algorithm/max.h>
-#include <__algorithm/max_element.h>
-#include <__algorithm/merge.h>
-#include <__algorithm/min.h>
-#include <__algorithm/min_element.h>
-#include <__algorithm/minmax.h>
-#include <__algorithm/minmax_element.h>
-#include <__algorithm/mismatch.h>
-#include <__algorithm/move.h>
-#include <__algorithm/next_permutation.h>
-#include <__algorithm/none_of.h>
-#include <__algorithm/nth_element.h>
-#include <__algorithm/partial_sort.h>
-#include <__algorithm/partition.h>
-#include <__algorithm/partition_point.h>
-#include <__algorithm/pop_heap.h>
-#include <__algorithm/prev_permutation.h>
-#include <__algorithm/push_heap.h>
-#include <__algorithm/remove.h>
-#include <__algorithm/replace.h>
-#include <__algorithm/reverse.h>
-#include <__algorithm/rotate.h>
-#include <__algorithm/sample.h>
-#include <__algorithm/search.h>
-#include <__algorithm/search_n.h>
-#include <__algorithm/set_difference.h>
-#include <__algorithm/set_intersection.h>
-#include <__algorithm/set_symmetric_difference.h>
-#include <__algorithm/set_union.h>
-#include <__algorithm/shift.h>
-#include <__algorithm/shuffle.h>
-#include <__algorithm/sift_down.h>
-#include <__algorithm/sort.h>
-#include <__algorithm/sort_heap.h>
-#include <__algorithm/stable_partition.h>
-#include <__algorithm/stable_sort.h>
-#include <__algorithm/transform.h>
-#include <__algorithm/uniform_int_distribution.h>
-#include <__algorithm/unique.h>
-#include <__algorithm/unwrap_iter.h>
-#include <__algorithm/upper_bound.h>
+#include <__debug>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
@@ -741,6 +666,5192 @@
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// I'd like to replace these with _VSTD::equal_to<void>, but can't because:
+// * That only works with C++14 and later, and
+// * We haven't included <functional> here.
+template <class _T1, class _T2 = _T1>
+struct __equal_to
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T1& __x, const _T2& __y) const {return __x == __y;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T1& __y) const {return __x == __y;}
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 bool operator()(const _T2& __x, const _T2& __y) const {return __x == __y;}
+};
+
+template <class _T1>
+struct __equal_to<_T1, _T1>
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
+};
+
+template <class _T1>
+struct __equal_to<const _T1, _T1>
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
+};
+
+template <class _T1>
+struct __equal_to<_T1, const _T1>
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x == __y;}
+};
+
+template <class _T1, class _T2 = _T1>
+struct __less
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
+
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T2& __y) const {return __x < __y;}
+
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T2& __x, const _T1& __y) const {return __x < __y;}
+
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T2& __x, const _T2& __y) const {return __x < __y;}
+};
+
+template <class _T1>
+struct __less<_T1, _T1>
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
+};
+
+template <class _T1>
+struct __less<const _T1, _T1>
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
+};
+
+template <class _T1>
+struct __less<_T1, const _T1>
+{
+ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+ bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
+};
+
+template <class _Predicate>
+class __invert // invert the sense of a comparison
+{
+private:
+ _Predicate __p_;
+public:
+ _LIBCPP_INLINE_VISIBILITY __invert() {}
+
+ _LIBCPP_INLINE_VISIBILITY
+ explicit __invert(_Predicate __p) : __p_(__p) {}
+
+ template <class _T1>
+ _LIBCPP_INLINE_VISIBILITY
+ bool operator()(const _T1& __x) {return !__p_(__x);}
+
+ template <class _T1, class _T2>
+ _LIBCPP_INLINE_VISIBILITY
+ bool operator()(const _T1& __x, const _T2& __y) {return __p_(__y, __x);}
+};
+
+// Perform division by two quickly for positive integers (llvm.org/PR39129)
+
+template <typename _Integral>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
+typename enable_if
+<
+ is_integral<_Integral>::value,
+ _Integral
+>::type
+__half_positive(_Integral __value)
+{
+ return static_cast<_Integral>(static_cast<typename make_unsigned<_Integral>::type>(__value) / 2);
+}
+
+template <typename _Tp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
+typename enable_if
+<
+ !is_integral<_Tp>::value,
+ _Tp
+>::type
+__half_positive(_Tp __value)
+{
+ return __value / 2;
+}
+
+#ifdef _LIBCPP_DEBUG
+
+template <class _Compare>
+struct __debug_less
+{
+ _Compare &__comp_;
+ _LIBCPP_CONSTEXPR_AFTER_CXX17
+ __debug_less(_Compare& __c) : __comp_(__c) {}
+
+ template <class _Tp, class _Up>
+ _LIBCPP_CONSTEXPR_AFTER_CXX17
+ bool operator()(const _Tp& __x, const _Up& __y)
+ {
+ bool __r = __comp_(__x, __y);
+ if (__r)
+ __do_compare_assert(0, __y, __x);
+ return __r;
+ }
+
+ template <class _Tp, class _Up>
+ _LIBCPP_CONSTEXPR_AFTER_CXX17
+ bool operator()(_Tp& __x, _Up& __y)
+ {
+ bool __r = __comp_(__x, __y);
+ if (__r)
+ __do_compare_assert(0, __y, __x);
+ return __r;
+ }
+
+ template <class _LHS, class _RHS>
+ _LIBCPP_CONSTEXPR_AFTER_CXX17
+ inline _LIBCPP_INLINE_VISIBILITY
+ decltype((void)declval<_Compare&>()(
+ declval<_LHS &>(), declval<_RHS &>()))
+ __do_compare_assert(int, _LHS & __l, _RHS & __r) {
+ _LIBCPP_ASSERT(!__comp_(__l, __r),
+ "Comparator does not induce a strict weak ordering");
+ }
+
+ template <class _LHS, class _RHS>
+ _LIBCPP_CONSTEXPR_AFTER_CXX17
+ inline _LIBCPP_INLINE_VISIBILITY
+ void __do_compare_assert(long, _LHS &, _RHS &) {}
+};
+
+#endif // _LIBCPP_DEBUG
+
+template <class _Comp>
+struct __comp_ref_type {
+ // Pass the comparator by lvalue reference. Or in debug mode, using a
+ // debugging wrapper that stores a reference.
+#ifndef _LIBCPP_DEBUG
+ typedef typename add_lvalue_reference<_Comp>::type type;
+#else
+ typedef __debug_less<_Comp> type;
+#endif
+};
+
+// all_of
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ if (!__pred(*__first))
+ return false;
+ return true;
+}
+
+// any_of
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+any_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ return true;
+ return false;
+}
+
+// none_of
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+none_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ return false;
+ return true;
+}
+
+// for_each
+
+template <class _InputIterator, class _Function>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_Function
+for_each(_InputIterator __first, _InputIterator __last, _Function __f)
+{
+ for (; __first != __last; ++__first)
+ __f(*__first);
+ return __f;
+}
+
+#if _LIBCPP_STD_VER > 14
+// for_each_n
+
+template <class _InputIterator, class _Size, class _Function>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_InputIterator
+for_each_n(_InputIterator __first, _Size __orig_n, _Function __f)
+{
+ typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ while (__n > 0)
+ {
+ __f(*__first);
+ ++__first;
+ --__n;
+ }
+ return __first;
+}
+#endif
+
+// find
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_InputIterator
+find(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
+{
+ for (; __first != __last; ++__first)
+ if (*__first == __value_)
+ break;
+ return __first;
+}
+
+// find_if
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_InputIterator
+find_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ break;
+ return __first;
+}
+
+// find_if_not
+
+template<class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_InputIterator
+find_if_not(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ if (!__pred(*__first))
+ break;
+ return __first;
+}
+
+// find_end
+
+template <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
+__find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred,
+ forward_iterator_tag, forward_iterator_tag)
+{
+ // modeled after search algorithm
+ _ForwardIterator1 __r = __last1; // __last1 is the "default" answer
+ if (__first2 == __last2)
+ return __r;
+ while (true)
+ {
+ while (true)
+ {
+ if (__first1 == __last1) // if source exhausted return last correct answer
+ return __r; // (or __last1 if never found)
+ if (__pred(*__first1, *__first2))
+ break;
+ ++__first1;
+ }
+ // *__first1 matches *__first2, now match elements after here
+ _ForwardIterator1 __m1 = __first1;
+ _ForwardIterator2 __m2 = __first2;
+ while (true)
+ {
+ if (++__m2 == __last2)
+ { // Pattern exhaused, record answer and search for another one
+ __r = __first1;
+ ++__first1;
+ break;
+ }
+ if (++__m1 == __last1) // Source exhausted, return last answer
+ return __r;
+ if (!__pred(*__m1, *__m2)) // mismatch, restart with a new __first
+ {
+ ++__first1;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _BinaryPredicate, class _BidirectionalIterator1, class _BidirectionalIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator1
+__find_end(_BidirectionalIterator1 __first1, _BidirectionalIterator1 __last1,
+ _BidirectionalIterator2 __first2, _BidirectionalIterator2 __last2, _BinaryPredicate __pred,
+ bidirectional_iterator_tag, bidirectional_iterator_tag)
+{
+ // modeled after search algorithm (in reverse)
+ if (__first2 == __last2)
+ return __last1; // Everything matches an empty sequence
+ _BidirectionalIterator1 __l1 = __last1;
+ _BidirectionalIterator2 __l2 = __last2;
+ --__l2;
+ while (true)
+ {
+ // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
+ while (true)
+ {
+ if (__first1 == __l1) // return __last1 if no element matches *__first2
+ return __last1;
+ if (__pred(*--__l1, *__l2))
+ break;
+ }
+ // *__l1 matches *__l2, now match elements before here
+ _BidirectionalIterator1 __m1 = __l1;
+ _BidirectionalIterator2 __m2 = __l2;
+ while (true)
+ {
+ if (__m2 == __first2) // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
+ return __m1;
+ if (__m1 == __first1) // Otherwise if source exhaused, pattern not found
+ return __last1;
+ if (!__pred(*--__m1, *--__m2)) // if there is a mismatch, restart with a new __l1
+ {
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1
+__find_end(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
+ _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
+ random_access_iterator_tag, random_access_iterator_tag)
+{
+ // Take advantage of knowing source and pattern lengths. Stop short when source is smaller than pattern
+ typename iterator_traits<_RandomAccessIterator2>::difference_type __len2 = __last2 - __first2;
+ if (__len2 == 0)
+ return __last1;
+ typename iterator_traits<_RandomAccessIterator1>::difference_type __len1 = __last1 - __first1;
+ if (__len1 < __len2)
+ return __last1;
+ const _RandomAccessIterator1 __s = __first1 + (__len2 - 1); // End of pattern match can't go before here
+ _RandomAccessIterator1 __l1 = __last1;
+ _RandomAccessIterator2 __l2 = __last2;
+ --__l2;
+ while (true)
+ {
+ while (true)
+ {
+ if (__s == __l1)
+ return __last1;
+ if (__pred(*--__l1, *__l2))
+ break;
+ }
+ _RandomAccessIterator1 __m1 = __l1;
+ _RandomAccessIterator2 __m2 = __l2;
+ while (true)
+ {
+ if (__m2 == __first2)
+ return __m1;
+ // no need to check range on __m1 because __s guarantees we have enough source
+ if (!__pred(*--__m1, *--__m2))
+ {
+ break;
+ }
+ }
+ }
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator1
+find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
+{
+ return _VSTD::__find_end<typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first1, __last1, __first2, __last2, __pred,
+ typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category());
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator1
+find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2)
+{
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+ return _VSTD::find_end(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
+}
+
+// find_first_of
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator1
+__find_first_of_ce(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
+{
+ for (; __first1 != __last1; ++__first1)
+ for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
+ if (__pred(*__first1, *__j))
+ return __first1;
+ return __last1;
+}
+
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator1
+find_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
+{
+ return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __pred);
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator1
+find_first_of(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2)
+{
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+ return _VSTD::__find_first_of_ce(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
+}
+
+// adjacent_find
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+adjacent_find(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
+{
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ {
+ if (__pred(*__first, *__i))
+ return __first;
+ __first = __i;
+ }
+ }
+ return __last;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+adjacent_find(_ForwardIterator __first, _ForwardIterator __last)
+{
+ typedef typename iterator_traits<_ForwardIterator>::value_type __v;
+ return _VSTD::adjacent_find(__first, __last, __equal_to<__v>());
+}
+
+// count
+
+template <class _InputIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+typename iterator_traits<_InputIterator>::difference_type
+count(_InputIterator __first, _InputIterator __last, const _Tp& __value_)
+{
+ typename iterator_traits<_InputIterator>::difference_type __r(0);
+ for (; __first != __last; ++__first)
+ if (*__first == __value_)
+ ++__r;
+ return __r;
+}
+
+// count_if
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+typename iterator_traits<_InputIterator>::difference_type
+count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ typename iterator_traits<_InputIterator>::difference_type __r(0);
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ ++__r;
+ return __r;
+}
+
+// mismatch
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _BinaryPredicate __pred)
+{
+ for (; __first1 != __last1; ++__first1, (void) ++__first2)
+ if (!__pred(*__first1, *__first2))
+ break;
+ return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
+{
+ typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+ typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+ return _VSTD::mismatch(__first1, __last1, __first2, __equal_to<__v1, __v2>());
+}
+
+#if _LIBCPP_STD_VER > 11
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2,
+ _BinaryPredicate __pred)
+{
+ for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
+ if (!__pred(*__first1, *__first2))
+ break;
+ return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+pair<_InputIterator1, _InputIterator2>
+mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2)
+{
+ typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+ typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+ return _VSTD::mismatch(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
+}
+#endif
+
+// equal
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred)
+{
+ for (; __first1 != __last1; ++__first1, (void) ++__first2)
+ if (!__pred(*__first1, *__first2))
+ return false;
+ return true;
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2)
+{
+ typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+ typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+ return _VSTD::equal(__first1, __last1, __first2, __equal_to<__v1, __v2>());
+}
+
+#if _LIBCPP_STD_VER > 11
+template <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+__equal(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred,
+ input_iterator_tag, input_iterator_tag )
+{
+ for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
+ if (!__pred(*__first1, *__first2))
+ return false;
+ return __first1 == __last1 && __first2 == __last2;
+}
+
+template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+__equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1,
+ _RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _BinaryPredicate __pred,
+ random_access_iterator_tag, random_access_iterator_tag )
+{
+ if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
+ return false;
+ return _VSTD::equal<_RandomAccessIterator1, _RandomAccessIterator2,
+ typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first1, __last1, __first2, __pred );
+}
+
+template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _BinaryPredicate __pred )
+{
+ return _VSTD::__equal<typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first1, __last1, __first2, __last2, __pred,
+ typename iterator_traits<_InputIterator1>::iterator_category(),
+ typename iterator_traits<_InputIterator2>::iterator_category());
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+equal(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2)
+{
+ typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+ typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+ return _VSTD::__equal(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>(),
+ typename iterator_traits<_InputIterator1>::iterator_category(),
+ typename iterator_traits<_InputIterator2>::iterator_category());
+}
+#endif
+
+// is_permutation
+
+template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _BinaryPredicate __pred)
+{
+// shorten sequences as much as possible by lopping of any equal prefix
+ for (; __first1 != __last1; ++__first1, (void) ++__first2)
+ if (!__pred(*__first1, *__first2))
+ break;
+ if (__first1 == __last1)
+ return true;
+
+// __first1 != __last1 && *__first1 != *__first2
+ typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
+ _D1 __l1 = _VSTD::distance(__first1, __last1);
+ if (__l1 == _D1(1))
+ return false;
+ _ForwardIterator2 __last2 = _VSTD::next(__first2, __l1);
+ // For each element in [f1, l1) see if there are the same number of
+ // equal elements in [f2, l2)
+ for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
+ {
+ // Have we already counted the number of *__i in [f1, l1)?
+ _ForwardIterator1 __match = __first1;
+ for (; __match != __i; ++__match)
+ if (__pred(*__match, *__i))
+ break;
+ if (__match == __i) {
+ // Count number of *__i in [f2, l2)
+ _D1 __c2 = 0;
+ for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
+ if (__pred(*__i, *__j))
+ ++__c2;
+ if (__c2 == 0)
+ return false;
+ // Count number of *__i in [__i, l1) (we can start with 1)
+ _D1 __c1 = 1;
+ for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
+ if (__pred(*__i, *__j))
+ ++__c1;
+ if (__c1 != __c2)
+ return false;
+ }
+ }
+ return true;
+}
+
+template<class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2)
+{
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+ return _VSTD::is_permutation(__first1, __last1, __first2, __equal_to<__v1, __v2>());
+}
+
+#if _LIBCPP_STD_VER > 11
+template<class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+__is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+ _BinaryPredicate __pred,
+ forward_iterator_tag, forward_iterator_tag )
+{
+// shorten sequences as much as possible by lopping of any equal prefix
+ for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void) ++__first2)
+ if (!__pred(*__first1, *__first2))
+ break;
+ if (__first1 == __last1)
+ return __first2 == __last2;
+ else if (__first2 == __last2)
+ return false;
+
+ typedef typename iterator_traits<_ForwardIterator1>::difference_type _D1;
+ _D1 __l1 = _VSTD::distance(__first1, __last1);
+
+ typedef typename iterator_traits<_ForwardIterator2>::difference_type _D2;
+ _D2 __l2 = _VSTD::distance(__first2, __last2);
+ if (__l1 != __l2)
+ return false;
+
+ // For each element in [f1, l1) see if there are the same number of
+ // equal elements in [f2, l2)
+ for (_ForwardIterator1 __i = __first1; __i != __last1; ++__i)
+ {
+ // Have we already counted the number of *__i in [f1, l1)?
+ _ForwardIterator1 __match = __first1;
+ for (; __match != __i; ++__match)
+ if (__pred(*__match, *__i))
+ break;
+ if (__match == __i) {
+ // Count number of *__i in [f2, l2)
+ _D1 __c2 = 0;
+ for (_ForwardIterator2 __j = __first2; __j != __last2; ++__j)
+ if (__pred(*__i, *__j))
+ ++__c2;
+ if (__c2 == 0)
+ return false;
+ // Count number of *__i in [__i, l1) (we can start with 1)
+ _D1 __c1 = 1;
+ for (_ForwardIterator1 __j = _VSTD::next(__i); __j != __last1; ++__j)
+ if (__pred(*__i, *__j))
+ ++__c1;
+ if (__c1 != __c2)
+ return false;
+ }
+ }
+ return true;
+}
+
+template<class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+__is_permutation(_RandomAccessIterator1 __first1, _RandomAccessIterator2 __last1,
+ _RandomAccessIterator1 __first2, _RandomAccessIterator2 __last2,
+ _BinaryPredicate __pred,
+ random_access_iterator_tag, random_access_iterator_tag )
+{
+ if ( _VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
+ return false;
+ return _VSTD::is_permutation<_RandomAccessIterator1, _RandomAccessIterator2,
+ typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first1, __last1, __first2, __pred );
+}
+
+template<class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+ _BinaryPredicate __pred )
+{
+ return _VSTD::__is_permutation<typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first1, __last1, __first2, __last2, __pred,
+ typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category());
+}
+
+template<class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2)
+{
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+ return _VSTD::__is_permutation(__first1, __last1, __first2, __last2,
+ __equal_to<__v1, __v2>(),
+ typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category());
+}
+#endif
+
+// search
+// __search is in <functional>
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator1
+search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __pred)
+{
+ return _VSTD::__search<typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first1, __last1, __first2, __last2, __pred,
+ typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category())
+ .first;
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator1
+search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2)
+{
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+ return _VSTD::search(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
+}
+
+
+#if _LIBCPP_STD_VER > 14
+template <class _ForwardIterator, class _Searcher>
+_LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator search(_ForwardIterator __f, _ForwardIterator __l, const _Searcher &__s)
+{ return __s(__f, __l).first; }
+#endif
+
+// search_n
+
+template <class _BinaryPredicate, class _ForwardIterator, class _Size, class _Tp>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+__search_n(_ForwardIterator __first, _ForwardIterator __last,
+ _Size __count, const _Tp& __value_, _BinaryPredicate __pred, forward_iterator_tag)
+{
+ if (__count <= 0)
+ return __first;
+ while (true)
+ {
+ // Find first element in sequence that matchs __value_, with a mininum of loop checks
+ while (true)
+ {
+ if (__first == __last) // return __last if no element matches __value_
+ return __last;
+ if (__pred(*__first, __value_))
+ break;
+ ++__first;
+ }
+ // *__first matches __value_, now match elements after here
+ _ForwardIterator __m = __first;
+ _Size __c(0);
+ while (true)
+ {
+ if (++__c == __count) // If pattern exhausted, __first is the answer (works for 1 element pattern)
+ return __first;
+ if (++__m == __last) // Otherwise if source exhaused, pattern not found
+ return __last;
+ if (!__pred(*__m, __value_)) // if there is a mismatch, restart with a new __first
+ {
+ __first = __m;
+ ++__first;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _BinaryPredicate, class _RandomAccessIterator, class _Size, class _Tp>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
+__search_n(_RandomAccessIterator __first, _RandomAccessIterator __last,
+ _Size __count, const _Tp& __value_, _BinaryPredicate __pred, random_access_iterator_tag)
+{
+ if (__count <= 0)
+ return __first;
+ _Size __len = static_cast<_Size>(__last - __first);
+ if (__len < __count)
+ return __last;
+ const _RandomAccessIterator __s = __last - (__count - 1); // Start of pattern match can't go beyond here
+ while (true)
+ {
+ // Find first element in sequence that matchs __value_, with a mininum of loop checks
+ while (true)
+ {
+ if (__first >= __s) // return __last if no element matches __value_
+ return __last;
+ if (__pred(*__first, __value_))
+ break;
+ ++__first;
+ }
+ // *__first matches __value_, now match elements after here
+ _RandomAccessIterator __m = __first;
+ _Size __c(0);
+ while (true)
+ {
+ if (++__c == __count) // If pattern exhausted, __first is the answer (works for 1 element pattern)
+ return __first;
+ ++__m; // no need to check range on __m because __s guarantees we have enough source
+ if (!__pred(*__m, __value_)) // if there is a mismatch, restart with a new __first
+ {
+ __first = __m;
+ ++__first;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _ForwardIterator, class _Size, class _Tp, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+search_n(_ForwardIterator __first, _ForwardIterator __last,
+ _Size __count, const _Tp& __value_, _BinaryPredicate __pred)
+{
+ return _VSTD::__search_n<typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first, __last, _VSTD::__convert_to_integral(__count), __value_, __pred,
+ typename iterator_traits<_ForwardIterator>::iterator_category());
+}
+
+template <class _ForwardIterator, class _Size, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+search_n(_ForwardIterator __first, _ForwardIterator __last, _Size __count, const _Tp& __value_)
+{
+ typedef typename iterator_traits<_ForwardIterator>::value_type __v;
+ return _VSTD::search_n(__first, __last, _VSTD::__convert_to_integral(__count),
+ __value_, __equal_to<__v, _Tp>());
+}
+
+// __unwrap_iter, __rewrap_iter
+
+// The job of __unwrap_iter is to lower contiguous iterators (such as
+// vector<T>::iterator) into pointers, to reduce the number of template
+// instantiations and to enable pointer-based optimizations e.g. in std::copy.
+// For iterators that are not contiguous, it must be a no-op.
+// In debug mode, we don't do this.
+//
+// __unwrap_iter is non-constexpr for user-defined iterators whose
+// `to_address` and/or `operator->` is non-constexpr. This is okay; but we
+// try to avoid doing __unwrap_iter in constant-evaluated contexts anyway.
+//
+// Some algorithms (e.g. std::copy, but not std::sort) need to convert an
+// "unwrapped" result back into a contiguous iterator. Since contiguous iterators
+// are random-access, we can do this portably using iterator arithmetic; this
+// is the job of __rewrap_iter.
+
+template <class _Iter, bool = __is_cpp17_contiguous_iterator<_Iter>::value>
+struct __unwrap_iter_impl {
+ static _LIBCPP_CONSTEXPR _Iter
+ __apply(_Iter __i) _NOEXCEPT {
+ return __i;
+ }
+};
+
+#if _LIBCPP_DEBUG_LEVEL < 2
+
+template <class _Iter>
+struct __unwrap_iter_impl<_Iter, true> {
+ static _LIBCPP_CONSTEXPR decltype(_VSTD::__to_address(declval<_Iter>()))
+ __apply(_Iter __i) _NOEXCEPT {
+ return _VSTD::__to_address(__i);
+ }
+};
+
+#endif // _LIBCPP_DEBUG_LEVEL < 2
+
+template<class _Iter, class _Impl = __unwrap_iter_impl<_Iter> >
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
+decltype(_Impl::__apply(declval<_Iter>()))
+__unwrap_iter(_Iter __i) _NOEXCEPT
+{
+ return _Impl::__apply(__i);
+}
+
+template<class _OrigIter>
+_OrigIter __rewrap_iter(_OrigIter, _OrigIter __result)
+{
+ return __result;
+}
+
+template<class _OrigIter, class _UnwrappedIter>
+_OrigIter __rewrap_iter(_OrigIter __first, _UnwrappedIter __result)
+{
+ // Precondition: __result is reachable from __first
+ // Precondition: _OrigIter is a contiguous iterator
+ return __first + (__result - _VSTD::__unwrap_iter(__first));
+}
+
+// copy
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+__copy_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ for (; __first != __last; ++__first, (void) ++__result)
+ *__result = *__first;
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+_OutputIterator
+__copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ return _VSTD::__copy_constexpr(__first, __last, __result);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_INLINE_VISIBILITY
+typename enable_if
+<
+ is_same<typename remove_const<_Tp>::type, _Up>::value &&
+ is_trivially_copy_assignable<_Up>::value,
+ _Up*
+>::type
+__copy(_Tp* __first, _Tp* __last, _Up* __result)
+{
+ const size_t __n = static_cast<size_t>(__last - __first);
+ if (__n > 0)
+ _VSTD::memmove(__result, __first, __n * sizeof(_Up));
+ return __result + __n;
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ if (__libcpp_is_constant_evaluated()) {
+ return _VSTD::__copy_constexpr(__first, __last, __result);
+ } else {
+ return _VSTD::__rewrap_iter(__result,
+ _VSTD::__copy(_VSTD::__unwrap_iter(__first),
+ _VSTD::__unwrap_iter(__last),
+ _VSTD::__unwrap_iter(__result)));
+ }
+}
+
+// copy_backward
+
+template <class _BidirectionalIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+__copy_backward_constexpr(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
+{
+ while (__first != __last)
+ *--__result = *--__last;
+ return __result;
+}
+
+template <class _BidirectionalIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+_OutputIterator
+__copy_backward(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
+{
+ return _VSTD::__copy_backward_constexpr(__first, __last, __result);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_INLINE_VISIBILITY
+typename enable_if
+<
+ is_same<typename remove_const<_Tp>::type, _Up>::value &&
+ is_trivially_copy_assignable<_Up>::value,
+ _Up*
+>::type
+__copy_backward(_Tp* __first, _Tp* __last, _Up* __result)
+{
+ const size_t __n = static_cast<size_t>(__last - __first);
+ if (__n > 0)
+ {
+ __result -= __n;
+ _VSTD::memmove(__result, __first, __n * sizeof(_Up));
+ }
+ return __result;
+}
+
+template <class _BidirectionalIterator1, class _BidirectionalIterator2>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_BidirectionalIterator2
+copy_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
+ _BidirectionalIterator2 __result)
+{
+ if (__libcpp_is_constant_evaluated()) {
+ return _VSTD::__copy_backward_constexpr(__first, __last, __result);
+ } else {
+ return _VSTD::__rewrap_iter(__result,
+ _VSTD::__copy_backward(_VSTD::__unwrap_iter(__first),
+ _VSTD::__unwrap_iter(__last),
+ _VSTD::__unwrap_iter(__result)));
+ }
+}
+
+// copy_if
+
+template<class _InputIterator, class _OutputIterator, class _Predicate>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+copy_if(_InputIterator __first, _InputIterator __last,
+ _OutputIterator __result, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ {
+ if (__pred(*__first))
+ {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+// copy_n
+
+template<class _InputIterator, class _Size, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+typename enable_if
+<
+ __is_cpp17_input_iterator<_InputIterator>::value &&
+ !__is_cpp17_random_access_iterator<_InputIterator>::value,
+ _OutputIterator
+>::type
+copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
+{
+ typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ if (__n > 0)
+ {
+ *__result = *__first;
+ ++__result;
+ for (--__n; __n > 0; --__n)
+ {
+ ++__first;
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+template<class _InputIterator, class _Size, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+typename enable_if
+<
+ __is_cpp17_random_access_iterator<_InputIterator>::value,
+ _OutputIterator
+>::type
+copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result)
+{
+ typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ return _VSTD::copy(__first, __first + __n, __result);
+}
+
+// move
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+_OutputIterator
+__move_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ for (; __first != __last; ++__first, (void) ++__result)
+ *__result = _VSTD::move(*__first);
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+_OutputIterator
+__move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ return _VSTD::__move_constexpr(__first, __last, __result);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+typename enable_if
+<
+ is_same<typename remove_const<_Tp>::type, _Up>::value &&
+ is_trivially_move_assignable<_Up>::value,
+ _Up*
+>::type
+__move(_Tp* __first, _Tp* __last, _Up* __result)
+{
+ const size_t __n = static_cast<size_t>(__last - __first);
+ if (__n > 0)
+ _VSTD::memmove(__result, __first, __n * sizeof(_Up));
+ return __result + __n;
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+move(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ if (__libcpp_is_constant_evaluated()) {
+ return _VSTD::__move_constexpr(__first, __last, __result);
+ } else {
+ return _VSTD::__rewrap_iter(__result,
+ _VSTD::__move(_VSTD::__unwrap_iter(__first),
+ _VSTD::__unwrap_iter(__last),
+ _VSTD::__unwrap_iter(__result)));
+ }
+}
+
+// move_backward
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+_OutputIterator
+__move_backward_constexpr(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ while (__first != __last)
+ *--__result = _VSTD::move(*--__last);
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+_OutputIterator
+__move_backward(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ return _VSTD::__move_backward_constexpr(__first, __last, __result);
+}
+
+template <class _Tp, class _Up>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+typename enable_if
+<
+ is_same<typename remove_const<_Tp>::type, _Up>::value &&
+ is_trivially_move_assignable<_Up>::value,
+ _Up*
+>::type
+__move_backward(_Tp* __first, _Tp* __last, _Up* __result)
+{
+ const size_t __n = static_cast<size_t>(__last - __first);
+ if (__n > 0)
+ {
+ __result -= __n;
+ _VSTD::memmove(__result, __first, __n * sizeof(_Up));
+ }
+ return __result;
+}
+
+template <class _BidirectionalIterator1, class _BidirectionalIterator2>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_BidirectionalIterator2
+move_backward(_BidirectionalIterator1 __first, _BidirectionalIterator1 __last,
+ _BidirectionalIterator2 __result)
+{
+ if (__libcpp_is_constant_evaluated()) {
+ return _VSTD::__move_backward_constexpr(__first, __last, __result);
+ } else {
+ return _VSTD::__rewrap_iter(__result,
+ _VSTD::__move_backward(_VSTD::__unwrap_iter(__first),
+ _VSTD::__unwrap_iter(__last),
+ _VSTD::__unwrap_iter(__result)));
+ }
+}
+
+// iter_swap
+
+// moved to <type_traits> for better swap / noexcept support
+
+// transform
+
+template <class _InputIterator, class _OutputIterator, class _UnaryOperation>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+transform(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _UnaryOperation __op)
+{
+ for (; __first != __last; ++__first, (void) ++__result)
+ *__result = __op(*__first);
+ return __result;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _BinaryOperation>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+transform(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2,
+ _OutputIterator __result, _BinaryOperation __binary_op)
+{
+ for (; __first1 != __last1; ++__first1, (void) ++__first2, ++__result)
+ *__result = __binary_op(*__first1, *__first2);
+ return __result;
+}
+
+// replace
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+replace(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __old_value, const _Tp& __new_value)
+{
+ for (; __first != __last; ++__first)
+ if (*__first == __old_value)
+ *__first = __new_value;
+}
+
+// replace_if
+
+template <class _ForwardIterator, class _Predicate, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+replace_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, const _Tp& __new_value)
+{
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ *__first = __new_value;
+}
+
+// replace_copy
+
+template <class _InputIterator, class _OutputIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+replace_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
+ const _Tp& __old_value, const _Tp& __new_value)
+{
+ for (; __first != __last; ++__first, (void) ++__result)
+ if (*__first == __old_value)
+ *__result = __new_value;
+ else
+ *__result = *__first;
+ return __result;
+}
+
+// replace_copy_if
+
+template <class _InputIterator, class _OutputIterator, class _Predicate, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+replace_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
+ _Predicate __pred, const _Tp& __new_value)
+{
+ for (; __first != __last; ++__first, (void) ++__result)
+ if (__pred(*__first))
+ *__result = __new_value;
+ else
+ *__result = *__first;
+ return __result;
+}
+
+// fill_n
+
+template <class _OutputIterator, class _Size, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
+{
+ for (; __n > 0; ++__first, (void) --__n)
+ *__first = __value_;
+ return __first;
+}
+
+template <class _OutputIterator, class _Size, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+fill_n(_OutputIterator __first, _Size __n, const _Tp& __value_)
+{
+ return _VSTD::__fill_n(__first, _VSTD::__convert_to_integral(__n), __value_);
+}
+
+// fill
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+__fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, forward_iterator_tag)
+{
+ for (; __first != __last; ++__first)
+ *__first = __value_;
+}
+
+template <class _RandomAccessIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+__fill(_RandomAccessIterator __first, _RandomAccessIterator __last, const _Tp& __value_, random_access_iterator_tag)
+{
+ _VSTD::fill_n(__first, __last - __first, __value_);
+}
+
+template <class _ForwardIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
+{
+ _VSTD::__fill(__first, __last, __value_, typename iterator_traits<_ForwardIterator>::iterator_category());
+}
+
+// generate
+
+template <class _ForwardIterator, class _Generator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+generate(_ForwardIterator __first, _ForwardIterator __last, _Generator __gen)
+{
+ for (; __first != __last; ++__first)
+ *__first = __gen();
+}
+
+// generate_n
+
+template <class _OutputIterator, class _Size, class _Generator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+generate_n(_OutputIterator __first, _Size __orig_n, _Generator __gen)
+{
+ typedef decltype(_VSTD::__convert_to_integral(__orig_n)) _IntegralSize;
+ _IntegralSize __n = __orig_n;
+ for (; __n > 0; ++__first, (void) --__n)
+ *__first = __gen();
+ return __first;
+}
+
+// remove
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+remove(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
+{
+ __first = _VSTD::find(__first, __last, __value_);
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ {
+ if (!(*__i == __value_))
+ {
+ *__first = _VSTD::move(*__i);
+ ++__first;
+ }
+ }
+ }
+ return __first;
+}
+
+// remove_if
+
+template <class _ForwardIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+remove_if(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
+{
+ __first = _VSTD::find_if<_ForwardIterator, typename add_lvalue_reference<_Predicate>::type>
+ (__first, __last, __pred);
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ {
+ if (!__pred(*__i))
+ {
+ *__first = _VSTD::move(*__i);
+ ++__first;
+ }
+ }
+ }
+ return __first;
+}
+
+// remove_copy
+
+template <class _InputIterator, class _OutputIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+remove_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, const _Tp& __value_)
+{
+ for (; __first != __last; ++__first)
+ {
+ if (!(*__first == __value_))
+ {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+// remove_copy_if
+
+template <class _InputIterator, class _OutputIterator, class _Predicate>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+remove_copy_if(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ {
+ if (!__pred(*__first))
+ {
+ *__result = *__first;
+ ++__result;
+ }
+ }
+ return __result;
+}
+
+// unique
+
+template <class _ForwardIterator, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+unique(_ForwardIterator __first, _ForwardIterator __last, _BinaryPredicate __pred)
+{
+ __first = _VSTD::adjacent_find<_ForwardIterator, typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first, __last, __pred);
+ if (__first != __last)
+ {
+ // ... a a ? ...
+ // f i
+ _ForwardIterator __i = __first;
+ for (++__i; ++__i != __last;)
+ if (!__pred(*__first, *__i))
+ *++__first = _VSTD::move(*__i);
+ ++__first;
+ }
+ return __first;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+unique(_ForwardIterator __first, _ForwardIterator __last)
+{
+ typedef typename iterator_traits<_ForwardIterator>::value_type __v;
+ return _VSTD::unique(__first, __last, __equal_to<__v>());
+}
+
+// unique_copy
+
+template <class _BinaryPredicate, class _InputIterator, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+__unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
+ input_iterator_tag, output_iterator_tag)
+{
+ if (__first != __last)
+ {
+ typename iterator_traits<_InputIterator>::value_type __t(*__first);
+ *__result = __t;
+ ++__result;
+ while (++__first != __last)
+ {
+ if (!__pred(__t, *__first))
+ {
+ __t = *__first;
+ *__result = __t;
+ ++__result;
+ }
+ }
+ }
+ return __result;
+}
+
+template <class _BinaryPredicate, class _ForwardIterator, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+__unique_copy(_ForwardIterator __first, _ForwardIterator __last, _OutputIterator __result, _BinaryPredicate __pred,
+ forward_iterator_tag, output_iterator_tag)
+{
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ *__result = *__i;
+ ++__result;
+ while (++__first != __last)
+ {
+ if (!__pred(*__i, *__first))
+ {
+ *__result = *__first;
+ ++__result;
+ __i = __first;
+ }
+ }
+ }
+ return __result;
+}
+
+template <class _BinaryPredicate, class _InputIterator, class _ForwardIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+__unique_copy(_InputIterator __first, _InputIterator __last, _ForwardIterator __result, _BinaryPredicate __pred,
+ input_iterator_tag, forward_iterator_tag)
+{
+ if (__first != __last)
+ {
+ *__result = *__first;
+ while (++__first != __last)
+ if (!__pred(*__result, *__first))
+ *++__result = *__first;
+ ++__result;
+ }
+ return __result;
+}
+
+template <class _InputIterator, class _OutputIterator, class _BinaryPredicate>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryPredicate __pred)
+{
+ return _VSTD::__unique_copy<typename add_lvalue_reference<_BinaryPredicate>::type>
+ (__first, __last, __result, __pred,
+ typename iterator_traits<_InputIterator>::iterator_category(),
+ typename iterator_traits<_OutputIterator>::iterator_category());
+}
+
+template <class _InputIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+unique_copy(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
+{
+ typedef typename iterator_traits<_InputIterator>::value_type __v;
+ return _VSTD::unique_copy(__first, __last, __result, __equal_to<__v>());
+}
+
+// reverse
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+__reverse(_BidirectionalIterator __first, _BidirectionalIterator __last, bidirectional_iterator_tag)
+{
+ while (__first != __last)
+ {
+ if (__first == --__last)
+ break;
+ _VSTD::iter_swap(__first, __last);
+ ++__first;
+ }
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+__reverse(_RandomAccessIterator __first, _RandomAccessIterator __last, random_access_iterator_tag)
+{
+ if (__first != __last)
+ for (; __first < --__last; ++__first)
+ _VSTD::iter_swap(__first, __last);
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+reverse(_BidirectionalIterator __first, _BidirectionalIterator __last)
+{
+ _VSTD::__reverse(__first, __last, typename iterator_traits<_BidirectionalIterator>::iterator_category());
+}
+
+// reverse_copy
+
+template <class _BidirectionalIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+reverse_copy(_BidirectionalIterator __first, _BidirectionalIterator __last, _OutputIterator __result)
+{
+ for (; __first != __last; ++__result)
+ *__result = *--__last;
+ return __result;
+}
+
+// rotate
+
+template <class _ForwardIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
+__rotate_left(_ForwardIterator __first, _ForwardIterator __last)
+{
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ value_type __tmp = _VSTD::move(*__first);
+ _ForwardIterator __lm1 = _VSTD::move(_VSTD::next(__first), __last, __first);
+ *__lm1 = _VSTD::move(__tmp);
+ return __lm1;
+}
+
+template <class _BidirectionalIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _BidirectionalIterator
+__rotate_right(_BidirectionalIterator __first, _BidirectionalIterator __last)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ _BidirectionalIterator __lm1 = _VSTD::prev(__last);
+ value_type __tmp = _VSTD::move(*__lm1);
+ _BidirectionalIterator __fp1 = _VSTD::move_backward(__first, __lm1, __last);
+ *__first = _VSTD::move(__tmp);
+ return __fp1;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX14 _ForwardIterator
+__rotate_forward(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
+{
+ _ForwardIterator __i = __middle;
+ while (true)
+ {
+ swap(*__first, *__i);
+ ++__first;
+ if (++__i == __last)
+ break;
+ if (__first == __middle)
+ __middle = __i;
+ }
+ _ForwardIterator __r = __first;
+ if (__first != __middle)
+ {
+ __i = __middle;
+ while (true)
+ {
+ swap(*__first, *__i);
+ ++__first;
+ if (++__i == __last)
+ {
+ if (__first == __middle)
+ break;
+ __i = __middle;
+ }
+ else if (__first == __middle)
+ __middle = __i;
+ }
+ }
+ return __r;
+}
+
+template<typename _Integral>
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR_AFTER_CXX14 _Integral
+__algo_gcd(_Integral __x, _Integral __y)
+{
+ do
+ {
+ _Integral __t = __x % __y;
+ __x = __y;
+ __y = __t;
+ } while (__y);
+ return __x;
+}
+
+template<typename _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX14 _RandomAccessIterator
+__rotate_gcd(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+
+ const difference_type __m1 = __middle - __first;
+ const difference_type __m2 = __last - __middle;
+ if (__m1 == __m2)
+ {
+ _VSTD::swap_ranges(__first, __middle, __middle);
+ return __middle;
+ }
+ const difference_type __g = _VSTD::__algo_gcd(__m1, __m2);
+ for (_RandomAccessIterator __p = __first + __g; __p != __first;)
+ {
+ value_type __t(_VSTD::move(*--__p));
+ _RandomAccessIterator __p1 = __p;
+ _RandomAccessIterator __p2 = __p1 + __m1;
+ do
+ {
+ *__p1 = _VSTD::move(*__p2);
+ __p1 = __p2;
+ const difference_type __d = __last - __p2;
+ if (__m1 < __d)
+ __p2 += __m1;
+ else
+ __p2 = __first + (__m1 - __d);
+ } while (__p2 != __p);
+ *__p1 = _VSTD::move(__t);
+ }
+ return __first + __m2;
+}
+
+template <class _ForwardIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _ForwardIterator
+__rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last,
+ _VSTD::forward_iterator_tag)
+{
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ if (is_trivially_move_assignable<value_type>::value)
+ {
+ if (_VSTD::next(__first) == __middle)
+ return _VSTD::__rotate_left(__first, __last);
+ }
+ return _VSTD::__rotate_forward(__first, __middle, __last);
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _BidirectionalIterator
+__rotate(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
+ bidirectional_iterator_tag)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ if (is_trivially_move_assignable<value_type>::value)
+ {
+ if (_VSTD::next(__first) == __middle)
+ return _VSTD::__rotate_left(__first, __last);
+ if (_VSTD::next(__middle) == __last)
+ return _VSTD::__rotate_right(__first, __last);
+ }
+ return _VSTD::__rotate_forward(__first, __middle, __last);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator
+__rotate(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
+ random_access_iterator_tag)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ if (is_trivially_move_assignable<value_type>::value)
+ {
+ if (_VSTD::next(__first) == __middle)
+ return _VSTD::__rotate_left(__first, __last);
+ if (_VSTD::next(__middle) == __last)
+ return _VSTD::__rotate_right(__first, __last);
+ return _VSTD::__rotate_gcd(__first, __middle, __last);
+ }
+ return _VSTD::__rotate_forward(__first, __middle, __last);
+}
+
+template <class _ForwardIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+rotate(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last)
+{
+ if (__first == __middle)
+ return __last;
+ if (__middle == __last)
+ return __first;
+ return _VSTD::__rotate(__first, __middle, __last,
+ typename iterator_traits<_ForwardIterator>::iterator_category());
+}
+
+// rotate_copy
+
+template <class _ForwardIterator, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+rotate_copy(_ForwardIterator __first, _ForwardIterator __middle, _ForwardIterator __last, _OutputIterator __result)
+{
+ return _VSTD::copy(__first, __middle, _VSTD::copy(__middle, __last, __result));
+}
+
+// min_element
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_ForwardIterator
+min_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
+{
+ static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
+ "std::min_element requires a ForwardIterator");
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ if (__comp(*__i, *__first))
+ __first = __i;
+ }
+ return __first;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_ForwardIterator
+min_element(_ForwardIterator __first, _ForwardIterator __last)
+{
+ return _VSTD::min_element(__first, __last,
+ __less<typename iterator_traits<_ForwardIterator>::value_type>());
+}
+
+// min
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+const _Tp&
+min(const _Tp& __a, const _Tp& __b, _Compare __comp)
+{
+ return __comp(__b, __a) ? __b : __a;
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+const _Tp&
+min(const _Tp& __a, const _Tp& __b)
+{
+ return _VSTD::min(__a, __b, __less<_Tp>());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template<class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_Tp
+min(initializer_list<_Tp> __t, _Compare __comp)
+{
+ return *_VSTD::min_element(__t.begin(), __t.end(), __comp);
+}
+
+template<class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_Tp
+min(initializer_list<_Tp> __t)
+{
+ return *_VSTD::min_element(__t.begin(), __t.end(), __less<_Tp>());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+// max_element
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_ForwardIterator
+max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
+{
+ static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
+ "std::max_element requires a ForwardIterator");
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ if (__comp(*__first, *__i))
+ __first = __i;
+ }
+ return __first;
+}
+
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_ForwardIterator
+max_element(_ForwardIterator __first, _ForwardIterator __last)
+{
+ return _VSTD::max_element(__first, __last,
+ __less<typename iterator_traits<_ForwardIterator>::value_type>());
+}
+
+// max
+
+template <class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+const _Tp&
+max(const _Tp& __a, const _Tp& __b, _Compare __comp)
+{
+ return __comp(__a, __b) ? __b : __a;
+}
+
+template <class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+const _Tp&
+max(const _Tp& __a, const _Tp& __b)
+{
+ return _VSTD::max(__a, __b, __less<_Tp>());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template<class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_Tp
+max(initializer_list<_Tp> __t, _Compare __comp)
+{
+ return *_VSTD::max_element(__t.begin(), __t.end(), __comp);
+}
+
+template<class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_Tp
+max(initializer_list<_Tp> __t)
+{
+ return *_VSTD::max_element(__t.begin(), __t.end(), __less<_Tp>());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER > 14
+// clamp
+template<class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
+const _Tp&
+clamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi, _Compare __comp)
+{
+ _LIBCPP_ASSERT(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
+ return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
+
+}
+
+template<class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
+const _Tp&
+clamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi)
+{
+ return _VSTD::clamp(__v, __lo, __hi, __less<_Tp>());
+}
+#endif
+
+// minmax_element
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<_ForwardIterator, _ForwardIterator>
+minmax_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
+{
+ static_assert(__is_cpp17_forward_iterator<_ForwardIterator>::value,
+ "std::minmax_element requires a ForwardIterator");
+ pair<_ForwardIterator, _ForwardIterator> __result(__first, __first);
+ if (__first != __last)
+ {
+ if (++__first != __last)
+ {
+ if (__comp(*__first, *__result.first))
+ __result.first = __first;
+ else
+ __result.second = __first;
+ while (++__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ if (++__first == __last)
+ {
+ if (__comp(*__i, *__result.first))
+ __result.first = __i;
+ else if (!__comp(*__i, *__result.second))
+ __result.second = __i;
+ break;
+ }
+ else
+ {
+ if (__comp(*__first, *__i))
+ {
+ if (__comp(*__first, *__result.first))
+ __result.first = __first;
+ if (!__comp(*__i, *__result.second))
+ __result.second = __i;
+ }
+ else
+ {
+ if (__comp(*__i, *__result.first))
+ __result.first = __i;
+ if (!__comp(*__first, *__result.second))
+ __result.second = __first;
+ }
+ }
+ }
+ }
+ }
+ return __result;
+}
+
+template <class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<_ForwardIterator, _ForwardIterator>
+minmax_element(_ForwardIterator __first, _ForwardIterator __last)
+{
+ return _VSTD::minmax_element(__first, __last,
+ __less<typename iterator_traits<_ForwardIterator>::value_type>());
+}
+
+// minmax
+
+template<class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<const _Tp&, const _Tp&>
+minmax(const _Tp& __a, const _Tp& __b, _Compare __comp)
+{
+ return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) :
+ pair<const _Tp&, const _Tp&>(__a, __b);
+}
+
+template<class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<const _Tp&, const _Tp&>
+minmax(const _Tp& __a, const _Tp& __b)
+{
+ return _VSTD::minmax(__a, __b, __less<_Tp>());
+}
+
+#ifndef _LIBCPP_CXX03_LANG
+
+template<class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<_Tp, _Tp>
+minmax(initializer_list<_Tp> __t, _Compare __comp)
+{
+ typedef typename initializer_list<_Tp>::const_iterator _Iter;
+ _Iter __first = __t.begin();
+ _Iter __last = __t.end();
+ pair<_Tp, _Tp> __result(*__first, *__first);
+
+ ++__first;
+ if (__t.size() % 2 == 0)
+ {
+ if (__comp(*__first, __result.first))
+ __result.first = *__first;
+ else
+ __result.second = *__first;
+ ++__first;
+ }
+
+ while (__first != __last)
+ {
+ _Tp __prev = *__first++;
+ if (__comp(*__first, __prev)) {
+ if ( __comp(*__first, __result.first)) __result.first = *__first;
+ if (!__comp(__prev, __result.second)) __result.second = __prev;
+ }
+ else {
+ if ( __comp(__prev, __result.first)) __result.first = __prev;
+ if (!__comp(*__first, __result.second)) __result.second = *__first;
+ }
+
+ __first++;
+ }
+ return __result;
+}
+
+template<class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+pair<_Tp, _Tp>
+minmax(initializer_list<_Tp> __t)
+{
+ return _VSTD::minmax(__t, __less<_Tp>());
+}
+
+#endif // _LIBCPP_CXX03_LANG
+
+// random_shuffle
+
+// __independent_bits_engine
+
+template <unsigned long long _Xp, size_t _Rp>
+struct __log2_imp
+{
+ static const size_t value = _Xp & ((unsigned long long)(1) << _Rp) ? _Rp
+ : __log2_imp<_Xp, _Rp - 1>::value;
+};
+
+template <unsigned long long _Xp>
+struct __log2_imp<_Xp, 0>
+{
+ static const size_t value = 0;
+};
+
+template <size_t _Rp>
+struct __log2_imp<0, _Rp>
+{
+ static const size_t value = _Rp + 1;
+};
+
+template <class _UIntType, _UIntType _Xp>
+struct __log2
+{
+ static const size_t value = __log2_imp<_Xp,
+ sizeof(_UIntType) * __CHAR_BIT__ - 1>::value;
+};
+
+template<class _Engine, class _UIntType>
+class __independent_bits_engine
+{
+public:
+ // types
+ typedef _UIntType result_type;
+
+private:
+ typedef typename _Engine::result_type _Engine_result_type;
+ typedef typename conditional
+ <
+ sizeof(_Engine_result_type) <= sizeof(result_type),
+ result_type,
+ _Engine_result_type
+ >::type _Working_result_type;
+
+ _Engine& __e_;
+ size_t __w_;
+ size_t __w0_;
+ size_t __n_;
+ size_t __n0_;
+ _Working_result_type __y0_;
+ _Working_result_type __y1_;
+ _Engine_result_type __mask0_;
+ _Engine_result_type __mask1_;
+
+#ifdef _LIBCPP_CXX03_LANG
+ static const _Working_result_type _Rp = _Engine::_Max - _Engine::_Min
+ + _Working_result_type(1);
+#else
+ static _LIBCPP_CONSTEXPR const _Working_result_type _Rp = _Engine::max() - _Engine::min()
+ + _Working_result_type(1);
+#endif
+ static _LIBCPP_CONSTEXPR const size_t __m = __log2<_Working_result_type, _Rp>::value;
+ static _LIBCPP_CONSTEXPR const size_t _WDt = numeric_limits<_Working_result_type>::digits;
+ static _LIBCPP_CONSTEXPR const size_t _EDt = numeric_limits<_Engine_result_type>::digits;
+
+public:
+ // constructors and seeding functions
+ __independent_bits_engine(_Engine& __e, size_t __w);
+
+ // generating functions
+ result_type operator()() {return __eval(integral_constant<bool, _Rp != 0>());}
+
+private:
+ result_type __eval(false_type);
+ result_type __eval(true_type);
+};
+
+template<class _Engine, class _UIntType>
+__independent_bits_engine<_Engine, _UIntType>
+ ::__independent_bits_engine(_Engine& __e, size_t __w)
+ : __e_(__e),
+ __w_(__w)
+{
+ __n_ = __w_ / __m + (__w_ % __m != 0);
+ __w0_ = __w_ / __n_;
+ if (_Rp == 0)
+ __y0_ = _Rp;
+ else if (__w0_ < _WDt)
+ __y0_ = (_Rp >> __w0_) << __w0_;
+ else
+ __y0_ = 0;
+ if (_Rp - __y0_ > __y0_ / __n_)
+ {
+ ++__n_;
+ __w0_ = __w_ / __n_;
+ if (__w0_ < _WDt)
+ __y0_ = (_Rp >> __w0_) << __w0_;
+ else
+ __y0_ = 0;
+ }
+ __n0_ = __n_ - __w_ % __n_;
+ if (__w0_ < _WDt - 1)
+ __y1_ = (_Rp >> (__w0_ + 1)) << (__w0_ + 1);
+ else
+ __y1_ = 0;
+ __mask0_ = __w0_ > 0 ? _Engine_result_type(~0) >> (_EDt - __w0_) :
+ _Engine_result_type(0);
+ __mask1_ = __w0_ < _EDt - 1 ?
+ _Engine_result_type(~0) >> (_EDt - (__w0_ + 1)) :
+ _Engine_result_type(~0);
+}
+
+template<class _Engine, class _UIntType>
+inline
+_UIntType
+__independent_bits_engine<_Engine, _UIntType>::__eval(false_type)
+{
+ return static_cast<result_type>(__e_() & __mask0_);
+}
+
+template<class _Engine, class _UIntType>
+_UIntType
+__independent_bits_engine<_Engine, _UIntType>::__eval(true_type)
+{
+ const size_t _WRt = numeric_limits<result_type>::digits;
+ result_type _Sp = 0;
+ for (size_t __k = 0; __k < __n0_; ++__k)
+ {
+ _Engine_result_type __u;
+ do
+ {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y0_);
+ if (__w0_ < _WRt)
+ _Sp <<= __w0_;
+ else
+ _Sp = 0;
+ _Sp += __u & __mask0_;
+ }
+ for (size_t __k = __n0_; __k < __n_; ++__k)
+ {
+ _Engine_result_type __u;
+ do
+ {
+ __u = __e_() - _Engine::min();
+ } while (__u >= __y1_);
+ if (__w0_ < _WRt - 1)
+ _Sp <<= __w0_ + 1;
+ else
+ _Sp = 0;
+ _Sp += __u & __mask1_;
+ }
+ return _Sp;
+}
+
+// uniform_int_distribution
+
+template<class _IntType = int>
+class uniform_int_distribution
+{
+public:
+ // types
+ typedef _IntType result_type;
+
+ class param_type
+ {
+ result_type __a_;
+ result_type __b_;
+ public:
+ typedef uniform_int_distribution distribution_type;
+
+ explicit param_type(result_type __a = 0,
+ result_type __b = numeric_limits<result_type>::max())
+ : __a_(__a), __b_(__b) {}
+
+ result_type a() const {return __a_;}
+ result_type b() const {return __b_;}
+
+ friend bool operator==(const param_type& __x, const param_type& __y)
+ {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;}
+ friend bool operator!=(const param_type& __x, const param_type& __y)
+ {return !(__x == __y);}
+ };
+
+private:
+ param_type __p_;
+
+public:
+ // constructors and reset functions
+#ifndef _LIBCPP_CXX03_LANG
+ uniform_int_distribution() : uniform_int_distribution(0) {}
+ explicit uniform_int_distribution(
+ result_type __a, result_type __b = numeric_limits<result_type>::max())
+ : __p_(param_type(__a, __b)) {}
+#else
+ explicit uniform_int_distribution(
+ result_type __a = 0,
+ result_type __b = numeric_limits<result_type>::max())
+ : __p_(param_type(__a, __b)) {}
+#endif
+ explicit uniform_int_distribution(const param_type& __p) : __p_(__p) {}
+ void reset() {}
+
+ // generating functions
+ template<class _URNG> result_type operator()(_URNG& __g)
+ {return (*this)(__g, __p_);}
+ template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p);
+
+ // property functions
+ result_type a() const {return __p_.a();}
+ result_type b() const {return __p_.b();}
+
+ param_type param() const {return __p_;}
+ void param(const param_type& __p) {__p_ = __p;}
+
+ result_type min() const {return a();}
+ result_type max() const {return b();}
+
+ friend bool operator==(const uniform_int_distribution& __x,
+ const uniform_int_distribution& __y)
+ {return __x.__p_ == __y.__p_;}
+ friend bool operator!=(const uniform_int_distribution& __x,
+ const uniform_int_distribution& __y)
+ {return !(__x == __y);}
+};
+
+template<class _IntType>
+template<class _URNG>
+typename uniform_int_distribution<_IntType>::result_type
+uniform_int_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p)
+_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
+{
+ typedef typename conditional<sizeof(result_type) <= sizeof(uint32_t),
+ uint32_t, uint64_t>::type _UIntType;
+ const _UIntType _Rp = _UIntType(__p.b()) - _UIntType(__p.a()) + _UIntType(1);
+ if (_Rp == 1)
+ return __p.a();
+ const size_t _Dt = numeric_limits<_UIntType>::digits;
+ typedef __independent_bits_engine<_URNG, _UIntType> _Eng;
+ if (_Rp == 0)
+ return static_cast<result_type>(_Eng(__g, _Dt)());
+ size_t __w = _Dt - __libcpp_clz(_Rp) - 1;
+ if ((_Rp & (numeric_limits<_UIntType>::max() >> (_Dt - __w))) != 0)
+ ++__w;
+ _Eng __e(__g, __w);
+ _UIntType __u;
+ do
+ {
+ __u = __e();
+ } while (__u >= _Rp);
+ return static_cast<result_type>(__u + __p.a());
+}
+
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE) \
+ || defined(_LIBCPP_BUILDING_LIBRARY)
+class _LIBCPP_TYPE_VIS __rs_default;
+
+_LIBCPP_FUNC_VIS __rs_default __rs_get();
+
+class _LIBCPP_TYPE_VIS __rs_default
+{
+ static unsigned __c_;
+
+ __rs_default();
+public:
+ typedef uint_fast32_t result_type;
+
+ static const result_type _Min = 0;
+ static const result_type _Max = 0xFFFFFFFF;
+
+ __rs_default(const __rs_default&);
+ ~__rs_default();
+
+ result_type operator()();
+
+ static _LIBCPP_CONSTEXPR result_type min() {return _Min;}
+ static _LIBCPP_CONSTEXPR result_type max() {return _Max;}
+
+ friend _LIBCPP_FUNC_VIS __rs_default __rs_get();
+};
+
+_LIBCPP_FUNC_VIS __rs_default __rs_get();
+
+template <class _RandomAccessIterator>
+_LIBCPP_DEPRECATED_IN_CXX14 void
+random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef uniform_int_distribution<ptrdiff_t> _Dp;
+ typedef typename _Dp::param_type _Pp;
+ difference_type __d = __last - __first;
+ if (__d > 1)
+ {
+ _Dp __uid;
+ __rs_default __g = __rs_get();
+ for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
+ {
+ difference_type __i = __uid(__g, _Pp(0, __d));
+ if (__i != difference_type(0))
+ swap(*__first, *(__first + __i));
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _RandomNumberGenerator>
+_LIBCPP_DEPRECATED_IN_CXX14 void
+random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
+#ifndef _LIBCPP_CXX03_LANG
+ _RandomNumberGenerator&& __rand)
+#else
+ _RandomNumberGenerator& __rand)
+#endif
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __d = __last - __first;
+ if (__d > 1)
+ {
+ for (--__last; __first < __last; ++__first, (void) --__d)
+ {
+ difference_type __i = __rand(__d);
+ if (__i != difference_type(0))
+ swap(*__first, *(__first + __i));
+ }
+ }
+}
+#endif
+
+template <class _PopulationIterator, class _SampleIterator, class _Distance,
+ class _UniformRandomNumberGenerator>
+_LIBCPP_INLINE_VISIBILITY
+_SampleIterator __sample(_PopulationIterator __first,
+ _PopulationIterator __last, _SampleIterator __output_iter,
+ _Distance __n,
+ _UniformRandomNumberGenerator & __g,
+ input_iterator_tag) {
+
+ _Distance __k = 0;
+ for (; __first != __last && __k < __n; ++__first, (void) ++__k)
+ __output_iter[__k] = *__first;
+ _Distance __sz = __k;
+ for (; __first != __last; ++__first, (void) ++__k) {
+ _Distance __r = uniform_int_distribution<_Distance>(0, __k)(__g);
+ if (__r < __sz)
+ __output_iter[__r] = *__first;
+ }
+ return __output_iter + _VSTD::min(__n, __k);
+}
+
+template <class _PopulationIterator, class _SampleIterator, class _Distance,
+ class _UniformRandomNumberGenerator>
+_LIBCPP_INLINE_VISIBILITY
+_SampleIterator __sample(_PopulationIterator __first,
+ _PopulationIterator __last, _SampleIterator __output_iter,
+ _Distance __n,
+ _UniformRandomNumberGenerator& __g,
+ forward_iterator_tag) {
+ _Distance __unsampled_sz = _VSTD::distance(__first, __last);
+ for (__n = _VSTD::min(__n, __unsampled_sz); __n != 0; ++__first) {
+ _Distance __r = uniform_int_distribution<_Distance>(0, --__unsampled_sz)(__g);
+ if (__r < __n) {
+ *__output_iter++ = *__first;
+ --__n;
+ }
+ }
+ return __output_iter;
+}
+
+template <class _PopulationIterator, class _SampleIterator, class _Distance,
+ class _UniformRandomNumberGenerator>
+_LIBCPP_INLINE_VISIBILITY
+_SampleIterator __sample(_PopulationIterator __first,
+ _PopulationIterator __last, _SampleIterator __output_iter,
+ _Distance __n, _UniformRandomNumberGenerator& __g) {
+ typedef typename iterator_traits<_PopulationIterator>::iterator_category
+ _PopCategory;
+ typedef typename iterator_traits<_PopulationIterator>::difference_type
+ _Difference;
+ static_assert(__is_cpp17_forward_iterator<_PopulationIterator>::value ||
+ __is_cpp17_random_access_iterator<_SampleIterator>::value,
+ "SampleIterator must meet the requirements of RandomAccessIterator");
+ typedef typename common_type<_Distance, _Difference>::type _CommonType;
+ _LIBCPP_ASSERT(__n >= 0, "N must be a positive number.");
+ return _VSTD::__sample(
+ __first, __last, __output_iter, _CommonType(__n),
+ __g, _PopCategory());
+}
+
+#if _LIBCPP_STD_VER > 14
+template <class _PopulationIterator, class _SampleIterator, class _Distance,
+ class _UniformRandomNumberGenerator>
+inline _LIBCPP_INLINE_VISIBILITY
+_SampleIterator sample(_PopulationIterator __first,
+ _PopulationIterator __last, _SampleIterator __output_iter,
+ _Distance __n, _UniformRandomNumberGenerator&& __g) {
+ return _VSTD::__sample(__first, __last, __output_iter, __n, __g);
+}
+#endif // _LIBCPP_STD_VER > 14
+
+template<class _RandomAccessIterator, class _UniformRandomNumberGenerator>
+ void shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
+ _UniformRandomNumberGenerator&& __g)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef uniform_int_distribution<ptrdiff_t> _Dp;
+ typedef typename _Dp::param_type _Pp;
+ difference_type __d = __last - __first;
+ if (__d > 1)
+ {
+ _Dp __uid;
+ for (--__last, (void) --__d; __first < __last; ++__first, (void) --__d)
+ {
+ difference_type __i = __uid(__g, _Pp(0, __d));
+ if (__i != difference_type(0))
+ swap(*__first, *(__first + __i));
+ }
+ }
+}
+
+#if _LIBCPP_STD_VER > 17
+
+// shift_left, shift_right
+
+template <class _ForwardIterator>
+inline _LIBCPP_INLINE_VISIBILITY constexpr
+_ForwardIterator
+shift_left(_ForwardIterator __first, _ForwardIterator __last,
+ typename iterator_traits<_ForwardIterator>::difference_type __n)
+{
+ if (__n == 0) {
+ return __last;
+ }
+
+ _ForwardIterator __m = __first;
+ if constexpr (__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
+ if (__n >= __last - __first) {
+ return __first;
+ }
+ __m += __n;
+ } else {
+ for (; __n > 0; --__n) {
+ if (__m == __last) {
+ return __first;
+ }
+ ++__m;
+ }
+ }
+ return _VSTD::move(__m, __last, __first);
+}
+
+template <class _ForwardIterator>
+inline _LIBCPP_INLINE_VISIBILITY constexpr
+_ForwardIterator
+shift_right(_ForwardIterator __first, _ForwardIterator __last,
+ typename iterator_traits<_ForwardIterator>::difference_type __n)
+{
+ if (__n == 0) {
+ return __first;
+ }
+
+ if constexpr (__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
+ decltype(__n) __d = __last - __first;
+ if (__n >= __d) {
+ return __last;
+ }
+ _ForwardIterator __m = __first + (__d - __n);
+ return _VSTD::move_backward(__first, __m, __last);
+ } else if constexpr (__is_cpp17_bidirectional_iterator<_ForwardIterator>::value) {
+ _ForwardIterator __m = __last;
+ for (; __n > 0; --__n) {
+ if (__m == __first) {
+ return __last;
+ }
+ --__m;
+ }
+ return _VSTD::move_backward(__first, __m, __last);
+ } else {
+ _ForwardIterator __ret = __first;
+ for (; __n > 0; --__n) {
+ if (__ret == __last) {
+ return __last;
+ }
+ ++__ret;
+ }
+
+ // We have an __n-element scratch space from __first to __ret.
+ // Slide an __n-element window [__trail, __lead) from left to right.
+ // We're essentially doing swap_ranges(__first, __ret, __trail, __lead)
+ // over and over; but once __lead reaches __last we needn't bother
+ // to save the values of elements [__trail, __last).
+
+ auto __trail = __first;
+ auto __lead = __ret;
+ while (__trail != __ret) {
+ if (__lead == __last) {
+ _VSTD::move(__first, __trail, __ret);
+ return __ret;
+ }
+ ++__trail;
+ ++__lead;
+ }
+
+ _ForwardIterator __mid = __first;
+ while (true) {
+ if (__lead == __last) {
+ __trail = _VSTD::move(__mid, __ret, __trail);
+ _VSTD::move(__first, __mid, __trail);
+ return __ret;
+ }
+ swap(*__mid, *__trail);
+ ++__mid;
+ ++__trail;
+ ++__lead;
+ if (__mid == __ret) {
+ __mid = __first;
+ }
+ }
+ }
+}
+
+#endif // _LIBCPP_STD_VER > 17
+
+// is_partitioned
+
+template <class _InputIterator, class _Predicate>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+is_partitioned(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ if (!__pred(*__first))
+ break;
+ if ( __first == __last )
+ return true;
+ ++__first;
+ for (; __first != __last; ++__first)
+ if (__pred(*__first))
+ return false;
+ return true;
+}
+
+// partition
+
+template <class _Predicate, class _ForwardIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+__partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred, forward_iterator_tag)
+{
+ while (true)
+ {
+ if (__first == __last)
+ return __first;
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ for (_ForwardIterator __p = __first; ++__p != __last;)
+ {
+ if (__pred(*__p))
+ {
+ swap(*__first, *__p);
+ ++__first;
+ }
+ }
+ return __first;
+}
+
+template <class _Predicate, class _BidirectionalIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator
+__partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
+ bidirectional_iterator_tag)
+{
+ while (true)
+ {
+ while (true)
+ {
+ if (__first == __last)
+ return __first;
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ do
+ {
+ if (__first == --__last)
+ return __first;
+ } while (!__pred(*__last));
+ swap(*__first, *__last);
+ ++__first;
+ }
+}
+
+template <class _ForwardIterator, class _Predicate>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
+{
+ return _VSTD::__partition<typename add_lvalue_reference<_Predicate>::type>
+ (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
+}
+
+// partition_copy
+
+template <class _InputIterator, class _OutputIterator1,
+ class _OutputIterator2, class _Predicate>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_OutputIterator1, _OutputIterator2>
+partition_copy(_InputIterator __first, _InputIterator __last,
+ _OutputIterator1 __out_true, _OutputIterator2 __out_false,
+ _Predicate __pred)
+{
+ for (; __first != __last; ++__first)
+ {
+ if (__pred(*__first))
+ {
+ *__out_true = *__first;
+ ++__out_true;
+ }
+ else
+ {
+ *__out_false = *__first;
+ ++__out_false;
+ }
+ }
+ return pair<_OutputIterator1, _OutputIterator2>(__out_true, __out_false);
+}
+
+// partition_point
+
+template<class _ForwardIterator, class _Predicate>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+partition_point(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
+{
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ difference_type __len = _VSTD::distance(__first, __last);
+ while (__len != 0)
+ {
+ difference_type __l2 = _VSTD::__half_positive(__len);
+ _ForwardIterator __m = __first;
+ _VSTD::advance(__m, __l2);
+ if (__pred(*__m))
+ {
+ __first = ++__m;
+ __len -= __l2 + 1;
+ }
+ else
+ __len = __l2;
+ }
+ return __first;
+}
+
+// stable_partition
+
+template <class _Predicate, class _ForwardIterator, class _Distance, class _Pair>
+_ForwardIterator
+__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
+ _Distance __len, _Pair __p, forward_iterator_tag __fit)
+{
+ // *__first is known to be false
+ // __len >= 1
+ if (__len == 1)
+ return __first;
+ if (__len == 2)
+ {
+ _ForwardIterator __m = __first;
+ if (__pred(*++__m))
+ {
+ swap(*__first, *__m);
+ return __m;
+ }
+ return __first;
+ }
+ if (__len <= __p.second)
+ { // The buffer is big enough to use
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
+ // Move the falses into the temporary buffer, and the trues to the front of the line
+ // Update __first to always point to the end of the trues
+ value_type* __t = __p.first;
+ ::new ((void*)__t) value_type(_VSTD::move(*__first));
+ __d.template __incr<value_type>();
+ ++__t;
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ {
+ if (__pred(*__i))
+ {
+ *__first = _VSTD::move(*__i);
+ ++__first;
+ }
+ else
+ {
+ ::new ((void*)__t) value_type(_VSTD::move(*__i));
+ __d.template __incr<value_type>();
+ ++__t;
+ }
+ }
+ // All trues now at start of range, all falses in buffer
+ // Move falses back into range, but don't mess up __first which points to first false
+ __i = __first;
+ for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
+ *__i = _VSTD::move(*__t2);
+ // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
+ return __first;
+ }
+ // Else not enough buffer, do in place
+ // __len >= 3
+ _ForwardIterator __m = __first;
+ _Distance __len2 = __len / 2; // __len2 >= 2
+ _VSTD::advance(__m, __len2);
+ // recurse on [__first, __m), *__first know to be false
+ // F?????????????????
+ // f m l
+ typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
+ _ForwardIterator __first_false = _VSTD::__stable_partition<_PredRef>(__first, __m, __pred, __len2, __p, __fit);
+ // TTTFFFFF??????????
+ // f ff m l
+ // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
+ _ForwardIterator __m1 = __m;
+ _ForwardIterator __second_false = __last;
+ _Distance __len_half = __len - __len2;
+ while (__pred(*__m1))
+ {
+ if (++__m1 == __last)
+ goto __second_half_done;
+ --__len_half;
+ }
+ // TTTFFFFFTTTF??????
+ // f ff m m1 l
+ __second_false = _VSTD::__stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __fit);
+__second_half_done:
+ // TTTFFFFFTTTTTFFFFF
+ // f ff m sf l
+ return _VSTD::rotate(__first_false, __m, __second_false);
+ // TTTTTTTTFFFFFFFFFF
+ // |
+}
+
+struct __return_temporary_buffer
+{
+ template <class _Tp>
+ _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::return_temporary_buffer(__p);}
+};
+
+template <class _Predicate, class _ForwardIterator>
+_ForwardIterator
+__stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred,
+ forward_iterator_tag)
+{
+ const unsigned __alloc_limit = 3; // might want to make this a function of trivial assignment
+ // Either prove all true and return __first or point to first false
+ while (true)
+ {
+ if (__first == __last)
+ return __first;
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ // We now have a reduced range [__first, __last)
+ // *__first is known to be false
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
+ difference_type __len = _VSTD::distance(__first, __last);
+ pair<value_type*, ptrdiff_t> __p(0, 0);
+ unique_ptr<value_type, __return_temporary_buffer> __h;
+ if (__len >= __alloc_limit)
+ {
+ __p = _VSTD::get_temporary_buffer<value_type>(__len);
+ __h.reset(__p.first);
+ }
+ return _VSTD::__stable_partition<typename add_lvalue_reference<_Predicate>::type>
+ (__first, __last, __pred, __len, __p, forward_iterator_tag());
+}
+
+template <class _Predicate, class _BidirectionalIterator, class _Distance, class _Pair>
+_BidirectionalIterator
+__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
+ _Distance __len, _Pair __p, bidirectional_iterator_tag __bit)
+{
+ // *__first is known to be false
+ // *__last is known to be true
+ // __len >= 2
+ if (__len == 2)
+ {
+ swap(*__first, *__last);
+ return __last;
+ }
+ if (__len == 3)
+ {
+ _BidirectionalIterator __m = __first;
+ if (__pred(*++__m))
+ {
+ swap(*__first, *__m);
+ swap(*__m, *__last);
+ return __last;
+ }
+ swap(*__m, *__last);
+ swap(*__first, *__m);
+ return __m;
+ }
+ if (__len <= __p.second)
+ { // The buffer is big enough to use
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__p.first, __d);
+ // Move the falses into the temporary buffer, and the trues to the front of the line
+ // Update __first to always point to the end of the trues
+ value_type* __t = __p.first;
+ ::new ((void*)__t) value_type(_VSTD::move(*__first));
+ __d.template __incr<value_type>();
+ ++__t;
+ _BidirectionalIterator __i = __first;
+ while (++__i != __last)
+ {
+ if (__pred(*__i))
+ {
+ *__first = _VSTD::move(*__i);
+ ++__first;
+ }
+ else
+ {
+ ::new ((void*)__t) value_type(_VSTD::move(*__i));
+ __d.template __incr<value_type>();
+ ++__t;
+ }
+ }
+ // move *__last, known to be true
+ *__first = _VSTD::move(*__i);
+ __i = ++__first;
+ // All trues now at start of range, all falses in buffer
+ // Move falses back into range, but don't mess up __first which points to first false
+ for (value_type* __t2 = __p.first; __t2 < __t; ++__t2, (void) ++__i)
+ *__i = _VSTD::move(*__t2);
+ // __h destructs moved-from values out of the temp buffer, but doesn't deallocate buffer
+ return __first;
+ }
+ // Else not enough buffer, do in place
+ // __len >= 4
+ _BidirectionalIterator __m = __first;
+ _Distance __len2 = __len / 2; // __len2 >= 2
+ _VSTD::advance(__m, __len2);
+ // recurse on [__first, __m-1], except reduce __m-1 until *(__m-1) is true, *__first know to be false
+ // F????????????????T
+ // f m l
+ _BidirectionalIterator __m1 = __m;
+ _BidirectionalIterator __first_false = __first;
+ _Distance __len_half = __len2;
+ while (!__pred(*--__m1))
+ {
+ if (__m1 == __first)
+ goto __first_half_done;
+ --__len_half;
+ }
+ // F???TFFF?????????T
+ // f m1 m l
+ typedef typename add_lvalue_reference<_Predicate>::type _PredRef;
+ __first_false = _VSTD::__stable_partition<_PredRef>(__first, __m1, __pred, __len_half, __p, __bit);
+__first_half_done:
+ // TTTFFFFF?????????T
+ // f ff m l
+ // recurse on [__m, __last], except increase __m until *(__m) is false, *__last know to be true
+ __m1 = __m;
+ _BidirectionalIterator __second_false = __last;
+ ++__second_false;
+ __len_half = __len - __len2;
+ while (__pred(*__m1))
+ {
+ if (++__m1 == __last)
+ goto __second_half_done;
+ --__len_half;
+ }
+ // TTTFFFFFTTTF?????T
+ // f ff m m1 l
+ __second_false = _VSTD::__stable_partition<_PredRef>(__m1, __last, __pred, __len_half, __p, __bit);
+__second_half_done:
+ // TTTFFFFFTTTTTFFFFF
+ // f ff m sf l
+ return _VSTD::rotate(__first_false, __m, __second_false);
+ // TTTTTTTTFFFFFFFFFF
+ // |
+}
+
+template <class _Predicate, class _BidirectionalIterator>
+_BidirectionalIterator
+__stable_partition(_BidirectionalIterator __first, _BidirectionalIterator __last, _Predicate __pred,
+ bidirectional_iterator_tag)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ const difference_type __alloc_limit = 4; // might want to make this a function of trivial assignment
+ // Either prove all true and return __first or point to first false
+ while (true)
+ {
+ if (__first == __last)
+ return __first;
+ if (!__pred(*__first))
+ break;
+ ++__first;
+ }
+ // __first points to first false, everything prior to __first is already set.
+ // Either prove [__first, __last) is all false and return __first, or point __last to last true
+ do
+ {
+ if (__first == --__last)
+ return __first;
+ } while (!__pred(*__last));
+ // We now have a reduced range [__first, __last]
+ // *__first is known to be false
+ // *__last is known to be true
+ // __len >= 2
+ difference_type __len = _VSTD::distance(__first, __last) + 1;
+ pair<value_type*, ptrdiff_t> __p(0, 0);
+ unique_ptr<value_type, __return_temporary_buffer> __h;
+ if (__len >= __alloc_limit)
+ {
+ __p = _VSTD::get_temporary_buffer<value_type>(__len);
+ __h.reset(__p.first);
+ }
+ return _VSTD::__stable_partition<typename add_lvalue_reference<_Predicate>::type>
+ (__first, __last, __pred, __len, __p, bidirectional_iterator_tag());
+}
+
+template <class _ForwardIterator, class _Predicate>
+inline _LIBCPP_INLINE_VISIBILITY
+_ForwardIterator
+stable_partition(_ForwardIterator __first, _ForwardIterator __last, _Predicate __pred)
+{
+ return _VSTD::__stable_partition<typename add_lvalue_reference<_Predicate>::type>
+ (__first, __last, __pred, typename iterator_traits<_ForwardIterator>::iterator_category());
+}
+
+// is_sorted_until
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+is_sorted_until(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
+{
+ if (__first != __last)
+ {
+ _ForwardIterator __i = __first;
+ while (++__i != __last)
+ {
+ if (__comp(*__i, *__first))
+ return __i;
+ __first = __i;
+ }
+ }
+ return __last;
+}
+
+template<class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+is_sorted_until(_ForwardIterator __first, _ForwardIterator __last)
+{
+ return _VSTD::is_sorted_until(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
+}
+
+// is_sorted
+
+template <class _ForwardIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_sorted(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp)
+{
+ return _VSTD::is_sorted_until(__first, __last, __comp) == __last;
+}
+
+template<class _ForwardIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_sorted(_ForwardIterator __first, _ForwardIterator __last)
+{
+ return _VSTD::is_sorted(__first, __last, __less<typename iterator_traits<_ForwardIterator>::value_type>());
+}
+
+// sort
+
+// stable, 2-3 compares, 0-2 swaps
+
+template <class _Compare, class _ForwardIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 unsigned
+__sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c)
+{
+ unsigned __r = 0;
+ if (!__c(*__y, *__x)) // if x <= y
+ {
+ if (!__c(*__z, *__y)) // if y <= z
+ return __r; // x <= y && y <= z
+ // x <= y && y > z
+ swap(*__y, *__z); // x <= z && y < z
+ __r = 1;
+ if (__c(*__y, *__x)) // if x > y
+ {
+ swap(*__x, *__y); // x < y && y <= z
+ __r = 2;
+ }
+ return __r; // x <= y && y < z
+ }
+ if (__c(*__z, *__y)) // x > y, if y > z
+ {
+ swap(*__x, *__z); // x < y && y < z
+ __r = 1;
+ return __r;
+ }
+ swap(*__x, *__y); // x > y && y <= z
+ __r = 1; // x < y && x <= z
+ if (__c(*__z, *__y)) // if y > z
+ {
+ swap(*__y, *__z); // x <= y && y < z
+ __r = 2;
+ }
+ return __r;
+} // x <= y && y <= z
+
+// stable, 3-6 compares, 0-5 swaps
+
+template <class _Compare, class _ForwardIterator>
+unsigned
+__sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
+ _ForwardIterator __x4, _Compare __c)
+{
+ unsigned __r = _VSTD::__sort3<_Compare>(__x1, __x2, __x3, __c);
+ if (__c(*__x4, *__x3))
+ {
+ swap(*__x3, *__x4);
+ ++__r;
+ if (__c(*__x3, *__x2))
+ {
+ swap(*__x2, *__x3);
+ ++__r;
+ if (__c(*__x2, *__x1))
+ {
+ swap(*__x1, *__x2);
+ ++__r;
+ }
+ }
+ }
+ return __r;
+}
+
+// stable, 4-10 compares, 0-9 swaps
+
+template <class _Compare, class _ForwardIterator>
+_LIBCPP_HIDDEN
+unsigned
+__sort5(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3,
+ _ForwardIterator __x4, _ForwardIterator __x5, _Compare __c)
+{
+ unsigned __r = _VSTD::__sort4<_Compare>(__x1, __x2, __x3, __x4, __c);
+ if (__c(*__x5, *__x4))
+ {
+ swap(*__x4, *__x5);
+ ++__r;
+ if (__c(*__x4, *__x3))
+ {
+ swap(*__x3, *__x4);
+ ++__r;
+ if (__c(*__x3, *__x2))
+ {
+ swap(*__x2, *__x3);
+ ++__r;
+ if (__c(*__x2, *__x1))
+ {
+ swap(*__x1, *__x2);
+ ++__r;
+ }
+ }
+ }
+ }
+ return __r;
+}
+
+// Assumes size > 0
+template <class _Compare, class _BidirectionalIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 void
+__selection_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
+{
+ _BidirectionalIterator __lm1 = __last;
+ for (--__lm1; __first != __lm1; ++__first)
+ {
+ _BidirectionalIterator __i = _VSTD::min_element<_BidirectionalIterator,
+ typename add_lvalue_reference<_Compare>::type>
+ (__first, __last, __comp);
+ if (__i != __first)
+ swap(*__first, *__i);
+ }
+}
+
+template <class _Compare, class _BidirectionalIterator>
+void
+__insertion_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ if (__first != __last)
+ {
+ _BidirectionalIterator __i = __first;
+ for (++__i; __i != __last; ++__i)
+ {
+ _BidirectionalIterator __j = __i;
+ value_type __t(_VSTD::move(*__j));
+ for (_BidirectionalIterator __k = __i; __k != __first && __comp(__t, *--__k); --__j)
+ *__j = _VSTD::move(*__k);
+ *__j = _VSTD::move(__t);
+ }
+ }
+}
+
+template <class _Compare, class _RandomAccessIterator>
+void
+__insertion_sort_3(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ _RandomAccessIterator __j = __first+2;
+ _VSTD::__sort3<_Compare>(__first, __first+1, __j, __comp);
+ for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
+ {
+ if (__comp(*__i, *__j))
+ {
+ value_type __t(_VSTD::move(*__i));
+ _RandomAccessIterator __k = __j;
+ __j = __i;
+ do
+ {
+ *__j = _VSTD::move(*__k);
+ __j = __k;
+ } while (__j != __first && __comp(__t, *--__k));
+ *__j = _VSTD::move(__t);
+ }
+ __j = __i;
+ }
+}
+
+template <class _Compare, class _RandomAccessIterator>
+bool
+__insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ switch (__last - __first)
+ {
+ case 0:
+ case 1:
+ return true;
+ case 2:
+ if (__comp(*--__last, *__first))
+ swap(*__first, *__last);
+ return true;
+ case 3:
+ _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
+ return true;
+ case 4:
+ _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
+ return true;
+ case 5:
+ _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
+ return true;
+ }
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ _RandomAccessIterator __j = __first+2;
+ _VSTD::__sort3<_Compare>(__first, __first+1, __j, __comp);
+ const unsigned __limit = 8;
+ unsigned __count = 0;
+ for (_RandomAccessIterator __i = __j+1; __i != __last; ++__i)
+ {
+ if (__comp(*__i, *__j))
+ {
+ value_type __t(_VSTD::move(*__i));
+ _RandomAccessIterator __k = __j;
+ __j = __i;
+ do
+ {
+ *__j = _VSTD::move(*__k);
+ __j = __k;
+ } while (__j != __first && __comp(__t, *--__k));
+ *__j = _VSTD::move(__t);
+ if (++__count == __limit)
+ return ++__i == __last;
+ }
+ __j = __i;
+ }
+ return true;
+}
+
+template <class _Compare, class _BidirectionalIterator>
+void
+__insertion_sort_move(_BidirectionalIterator __first1, _BidirectionalIterator __last1,
+ typename iterator_traits<_BidirectionalIterator>::value_type* __first2, _Compare __comp)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ if (__first1 != __last1)
+ {
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__first2, __d);
+ value_type* __last2 = __first2;
+ ::new ((void*)__last2) value_type(_VSTD::move(*__first1));
+ __d.template __incr<value_type>();
+ for (++__last2; ++__first1 != __last1; ++__last2)
+ {
+ value_type* __j2 = __last2;
+ value_type* __i2 = __j2;
+ if (__comp(*__first1, *--__i2))
+ {
+ ::new ((void*)__j2) value_type(_VSTD::move(*__i2));
+ __d.template __incr<value_type>();
+ for (--__j2; __i2 != __first2 && __comp(*__first1, *--__i2); --__j2)
+ *__j2 = _VSTD::move(*__i2);
+ *__j2 = _VSTD::move(*__first1);
+ }
+ else
+ {
+ ::new ((void*)__j2) value_type(_VSTD::move(*__first1));
+ __d.template __incr<value_type>();
+ }
+ }
+ __h.release();
+ }
+}
+
+template <class _Compare, class _RandomAccessIterator>
+void
+__sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ const difference_type __limit = is_trivially_copy_constructible<value_type>::value &&
+ is_trivially_copy_assignable<value_type>::value ? 30 : 6;
+ while (true)
+ {
+ __restart:
+ difference_type __len = __last - __first;
+ switch (__len)
+ {
+ case 0:
+ case 1:
+ return;
+ case 2:
+ if (__comp(*--__last, *__first))
+ swap(*__first, *__last);
+ return;
+ case 3:
+ _VSTD::__sort3<_Compare>(__first, __first+1, --__last, __comp);
+ return;
+ case 4:
+ _VSTD::__sort4<_Compare>(__first, __first+1, __first+2, --__last, __comp);
+ return;
+ case 5:
+ _VSTD::__sort5<_Compare>(__first, __first+1, __first+2, __first+3, --__last, __comp);
+ return;
+ }
+ if (__len <= __limit)
+ {
+ _VSTD::__insertion_sort_3<_Compare>(__first, __last, __comp);
+ return;
+ }
+ // __len > 5
+ _RandomAccessIterator __m = __first;
+ _RandomAccessIterator __lm1 = __last;
+ --__lm1;
+ unsigned __n_swaps;
+ {
+ difference_type __delta;
+ if (__len >= 1000)
+ {
+ __delta = __len/2;
+ __m += __delta;
+ __delta /= 2;
+ __n_swaps = _VSTD::__sort5<_Compare>(__first, __first + __delta, __m, __m+__delta, __lm1, __comp);
+ }
+ else
+ {
+ __delta = __len/2;
+ __m += __delta;
+ __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, __lm1, __comp);
+ }
+ }
+ // *__m is median
+ // partition [__first, __m) < *__m and *__m <= [__m, __last)
+ // (this inhibits tossing elements equivalent to __m around unnecessarily)
+ _RandomAccessIterator __i = __first;
+ _RandomAccessIterator __j = __lm1;
+ // j points beyond range to be tested, *__m is known to be <= *__lm1
+ // The search going up is known to be guarded but the search coming down isn't.
+ // Prime the downward search with a guard.
+ if (!__comp(*__i, *__m)) // if *__first == *__m
+ {
+ // *__first == *__m, *__first doesn't go in first part
+ // manually guard downward moving __j against __i
+ while (true)
+ {
+ if (__i == --__j)
+ {
+ // *__first == *__m, *__m <= all other elements
+ // Parition instead into [__first, __i) == *__first and *__first < [__i, __last)
+ ++__i; // __first + 1
+ __j = __last;
+ if (!__comp(*__first, *--__j)) // we need a guard if *__first == *(__last-1)
+ {
+ while (true)
+ {
+ if (__i == __j)
+ return; // [__first, __last) all equivalent elements
+ if (__comp(*__first, *__i))
+ {
+ swap(*__i, *__j);
+ ++__n_swaps;
+ ++__i;
+ break;
+ }
+ ++__i;
+ }
+ }
+ // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
+ if (__i == __j)
+ return;
+ while (true)
+ {
+ while (!__comp(*__first, *__i))
+ ++__i;
+ while (__comp(*__first, *--__j))
+ ;
+ if (__i >= __j)
+ break;
+ swap(*__i, *__j);
+ ++__n_swaps;
+ ++__i;
+ }
+ // [__first, __i) == *__first and *__first < [__i, __last)
+ // The first part is sorted, sort the second part
+ // _VSTD::__sort<_Compare>(__i, __last, __comp);
+ __first = __i;
+ goto __restart;
+ }
+ if (__comp(*__j, *__m))
+ {
+ swap(*__i, *__j);
+ ++__n_swaps;
+ break; // found guard for downward moving __j, now use unguarded partition
+ }
+ }
+ }
+ // It is known that *__i < *__m
+ ++__i;
+ // j points beyond range to be tested, *__m is known to be <= *__lm1
+ // if not yet partitioned...
+ if (__i < __j)
+ {
+ // known that *(__i - 1) < *__m
+ // known that __i <= __m
+ while (true)
+ {
+ // __m still guards upward moving __i
+ while (__comp(*__i, *__m))
+ ++__i;
+ // It is now known that a guard exists for downward moving __j
+ while (!__comp(*--__j, *__m))
+ ;
+ if (__i > __j)
+ break;
+ swap(*__i, *__j);
+ ++__n_swaps;
+ // It is known that __m != __j
+ // If __m just moved, follow it
+ if (__m == __i)
+ __m = __j;
+ ++__i;
+ }
+ }
+ // [__first, __i) < *__m and *__m <= [__i, __last)
+ if (__i != __m && __comp(*__m, *__i))
+ {
+ swap(*__i, *__m);
+ ++__n_swaps;
+ }
+ // [__first, __i) < *__i and *__i <= [__i+1, __last)
+ // If we were given a perfect partition, see if insertion sort is quick...
+ if (__n_swaps == 0)
+ {
+ bool __fs = _VSTD::__insertion_sort_incomplete<_Compare>(__first, __i, __comp);
+ if (_VSTD::__insertion_sort_incomplete<_Compare>(__i+1, __last, __comp))
+ {
+ if (__fs)
+ return;
+ __last = __i;
+ continue;
+ }
+ else
+ {
+ if (__fs)
+ {
+ __first = ++__i;
+ continue;
+ }
+ }
+ }
+ // sort smaller range with recursive call and larger with tail recursion elimination
+ if (__i - __first < __last - __i)
+ {
+ _VSTD::__sort<_Compare>(__first, __i, __comp);
+ // _VSTD::__sort<_Compare>(__i+1, __last, __comp);
+ __first = ++__i;
+ }
+ else
+ {
+ _VSTD::__sort<_Compare>(__i+1, __last, __comp);
+ // _VSTD::__sort<_Compare>(__first, __i, __comp);
+ __last = __i;
+ }
+ }
+}
+
+template <class _Compare, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+__sort(_Tp** __first, _Tp** __last, __less<_Tp*>&)
+{
+ __less<uintptr_t> __comp;
+ _VSTD::__sort<__less<uintptr_t>&, uintptr_t*>((uintptr_t*)__first, (uintptr_t*)__last, __comp);
+}
+
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<char>&, char*>(char*, char*, __less<char>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<short>&, short*>(short*, short*, __less<short>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<int>&, int*>(int*, int*, __less<int>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long>&, long*>(long*, long*, __less<long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<float>&, float*>(float*, float*, __less<float>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<double>&, double*>(double*, double*, __less<double>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
+
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<char>&, char*>(char*, char*, __less<char>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<wchar_t>&, wchar_t*>(wchar_t*, wchar_t*, __less<wchar_t>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<signed char>&, signed char*>(signed char*, signed char*, __less<signed char>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned char>&, unsigned char*>(unsigned char*, unsigned char*, __less<unsigned char>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<short>&, short*>(short*, short*, __less<short>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned short>&, unsigned short*>(unsigned short*, unsigned short*, __less<unsigned short>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<int>&, int*>(int*, int*, __less<int>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned>&, unsigned*>(unsigned*, unsigned*, __less<unsigned>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long>&, long*>(long*, long*, __less<long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long>&, unsigned long*>(unsigned long*, unsigned long*, __less<unsigned long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long long>&, long long*>(long long*, long long*, __less<long long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<unsigned long long>&, unsigned long long*>(unsigned long long*, unsigned long long*, __less<unsigned long long>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<float>&, float*>(float*, float*, __less<float>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<double>&, double*>(double*, double*, __less<double>&))
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less<long double>&, long double*>(long double*, long double*, __less<long double>&))
+
+_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS unsigned __sort5<__less<long double>&, long double*>(long double*, long double*, long double*, long double*, long double*, __less<long double>&))
+
+// lower_bound
+
+template <class _Compare, class _ForwardIterator, class _Tp>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+__lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ difference_type __len = _VSTD::distance(__first, __last);
+ while (__len != 0)
+ {
+ difference_type __l2 = _VSTD::__half_positive(__len);
+ _ForwardIterator __m = __first;
+ _VSTD::advance(__m, __l2);
+ if (__comp(*__m, __value_))
+ {
+ __first = ++__m;
+ __len -= __l2 + 1;
+ }
+ else
+ __len = __l2;
+ }
+ return __first;
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
+ return _VSTD::__lower_bound<_Comp_ref>(__first, __last, __value_, __comp);
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
+{
+ return _VSTD::lower_bound(__first, __last, __value_,
+ __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
+}
+
+// upper_bound
+
+template <class _Compare, class _ForwardIterator, class _Tp>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator
+__upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ difference_type __len = _VSTD::distance(__first, __last);
+ while (__len != 0)
+ {
+ difference_type __l2 = _VSTD::__half_positive(__len);
+ _ForwardIterator __m = __first;
+ _VSTD::advance(__m, __l2);
+ if (__comp(__value_, *__m))
+ __len = __l2;
+ else
+ {
+ __first = ++__m;
+ __len -= __l2 + 1;
+ }
+ }
+ return __first;
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename add_lvalue_reference<_Compare>::type _Comp_ref;
+ return _VSTD::__upper_bound<_Comp_ref>(__first, __last, __value_, __comp);
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_ForwardIterator
+upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
+{
+ return _VSTD::upper_bound(__first, __last, __value_,
+ __less<_Tp, typename iterator_traits<_ForwardIterator>::value_type>());
+}
+
+// equal_range
+
+template <class _Compare, class _ForwardIterator, class _Tp>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 pair<_ForwardIterator, _ForwardIterator>
+__equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type;
+ difference_type __len = _VSTD::distance(__first, __last);
+ while (__len != 0)
+ {
+ difference_type __l2 = _VSTD::__half_positive(__len);
+ _ForwardIterator __m = __first;
+ _VSTD::advance(__m, __l2);
+ if (__comp(*__m, __value_))
+ {
+ __first = ++__m;
+ __len -= __l2 + 1;
+ }
+ else if (__comp(__value_, *__m))
+ {
+ __last = __m;
+ __len = __l2;
+ }
+ else
+ {
+ _ForwardIterator __mp1 = __m;
+ return pair<_ForwardIterator, _ForwardIterator>
+ (
+ _VSTD::__lower_bound<_Compare>(__first, __m, __value_, __comp),
+ _VSTD::__upper_bound<_Compare>(++__mp1, __last, __value_, __comp)
+ );
+ }
+ }
+ return pair<_ForwardIterator, _ForwardIterator>(__first, __first);
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+pair<_ForwardIterator, _ForwardIterator>
+equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__equal_range<_Comp_ref>(__first, __last, __value_, __comp);
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+pair<_ForwardIterator, _ForwardIterator>
+equal_range(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
+{
+ return _VSTD::equal_range(__first, __last, __value_,
+ __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
+}
+
+// binary_search
+
+template <class _Compare, class _ForwardIterator, class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+__binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ __first = _VSTD::__lower_bound<_Compare>(__first, __last, __value_, __comp);
+ return __first != __last && !__comp(__value_, *__first);
+}
+
+template <class _ForwardIterator, class _Tp, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__binary_search<_Comp_ref>(__first, __last, __value_, __comp);
+}
+
+template <class _ForwardIterator, class _Tp>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_)
+{
+ return _VSTD::binary_search(__first, __last, __value_,
+ __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
+}
+
+// merge
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+__merge(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ for (; __first1 != __last1; ++__result)
+ {
+ if (__first2 == __last2)
+ return _VSTD::copy(__first1, __last1, __result);
+ if (__comp(*__first2, *__first1))
+ {
+ *__result = *__first2;
+ ++__first2;
+ }
+ else
+ {
+ *__result = *__first1;
+ ++__first1;
+ }
+ }
+ return _VSTD::copy(__first2, __last2, __result);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+merge(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__merge<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+merge(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
+{
+ typedef typename iterator_traits<_InputIterator1>::value_type __v1;
+ typedef typename iterator_traits<_InputIterator2>::value_type __v2;
+ return _VSTD::merge(__first1, __last1, __first2, __last2, __result, __less<__v1, __v2>());
+}
+
+// inplace_merge
+
+template <class _Compare, class _InputIterator1, class _InputIterator2,
+ class _OutputIterator>
+void __half_inplace_merge(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2,
+ _OutputIterator __result, _Compare __comp)
+{
+ for (; __first1 != __last1; ++__result)
+ {
+ if (__first2 == __last2)
+ {
+ _VSTD::move(__first1, __last1, __result);
+ return;
+ }
+
+ if (__comp(*__first2, *__first1))
+ {
+ *__result = _VSTD::move(*__first2);
+ ++__first2;
+ }
+ else
+ {
+ *__result = _VSTD::move(*__first1);
+ ++__first1;
+ }
+ }
+ // __first2 through __last2 are already in the right spot.
+}
+
+template <class _Compare, class _BidirectionalIterator>
+void
+__buffered_inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
+ _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
+ typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
+ typename iterator_traits<_BidirectionalIterator>::value_type* __buff)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
+ if (__len1 <= __len2)
+ {
+ value_type* __p = __buff;
+ for (_BidirectionalIterator __i = __first; __i != __middle; __d.template __incr<value_type>(), (void) ++__i, (void) ++__p)
+ ::new ((void*)__p) value_type(_VSTD::move(*__i));
+ _VSTD::__half_inplace_merge<_Compare>(__buff, __p, __middle, __last, __first, __comp);
+ }
+ else
+ {
+ value_type* __p = __buff;
+ for (_BidirectionalIterator __i = __middle; __i != __last; __d.template __incr<value_type>(), (void) ++__i, (void) ++__p)
+ ::new ((void*)__p) value_type(_VSTD::move(*__i));
+ typedef reverse_iterator<_BidirectionalIterator> _RBi;
+ typedef reverse_iterator<value_type*> _Rv;
+ typedef __invert<_Compare> _Inverted;
+ _VSTD::__half_inplace_merge<_Inverted>(_Rv(__p), _Rv(__buff),
+ _RBi(__middle), _RBi(__first),
+ _RBi(__last), _Inverted(__comp));
+ }
+}
+
+template <class _Compare, class _BidirectionalIterator>
+void
+__inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
+ _Compare __comp, typename iterator_traits<_BidirectionalIterator>::difference_type __len1,
+ typename iterator_traits<_BidirectionalIterator>::difference_type __len2,
+ typename iterator_traits<_BidirectionalIterator>::value_type* __buff, ptrdiff_t __buff_size)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ while (true)
+ {
+ // if __middle == __last, we're done
+ if (__len2 == 0)
+ return;
+ if (__len1 <= __buff_size || __len2 <= __buff_size)
+ return _VSTD::__buffered_inplace_merge<_Compare>
+ (__first, __middle, __last, __comp, __len1, __len2, __buff);
+ // shrink [__first, __middle) as much as possible (with no moves), returning if it shrinks to 0
+ for (; true; ++__first, (void) --__len1)
+ {
+ if (__len1 == 0)
+ return;
+ if (__comp(*__middle, *__first))
+ break;
+ }
+ // __first < __middle < __last
+ // *__first > *__middle
+ // partition [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last) such that
+ // all elements in:
+ // [__first, __m1) <= [__middle, __m2)
+ // [__middle, __m2) < [__m1, __middle)
+ // [__m1, __middle) <= [__m2, __last)
+ // and __m1 or __m2 is in the middle of its range
+ _BidirectionalIterator __m1; // "median" of [__first, __middle)
+ _BidirectionalIterator __m2; // "median" of [__middle, __last)
+ difference_type __len11; // distance(__first, __m1)
+ difference_type __len21; // distance(__middle, __m2)
+ // binary search smaller range
+ if (__len1 < __len2)
+ { // __len >= 1, __len2 >= 2
+ __len21 = __len2 / 2;
+ __m2 = __middle;
+ _VSTD::advance(__m2, __len21);
+ __m1 = _VSTD::__upper_bound<_Compare>(__first, __middle, *__m2, __comp);
+ __len11 = _VSTD::distance(__first, __m1);
+ }
+ else
+ {
+ if (__len1 == 1)
+ { // __len1 >= __len2 && __len2 > 0, therefore __len2 == 1
+ // It is known *__first > *__middle
+ swap(*__first, *__middle);
+ return;
+ }
+ // __len1 >= 2, __len2 >= 1
+ __len11 = __len1 / 2;
+ __m1 = __first;
+ _VSTD::advance(__m1, __len11);
+ __m2 = _VSTD::__lower_bound<_Compare>(__middle, __last, *__m1, __comp);
+ __len21 = _VSTD::distance(__middle, __m2);
+ }
+ difference_type __len12 = __len1 - __len11; // distance(__m1, __middle)
+ difference_type __len22 = __len2 - __len21; // distance(__m2, __last)
+ // [__first, __m1) [__m1, __middle) [__middle, __m2) [__m2, __last)
+ // swap middle two partitions
+ __middle = _VSTD::rotate(__m1, __middle, __m2);
+ // __len12 and __len21 now have swapped meanings
+ // merge smaller range with recursive call and larger with tail recursion elimination
+ if (__len11 + __len21 < __len12 + __len22)
+ {
+ _VSTD::__inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
+// _VSTD::__inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
+ __first = __middle;
+ __middle = __m2;
+ __len1 = __len12;
+ __len2 = __len22;
+ }
+ else
+ {
+ _VSTD::__inplace_merge<_Compare>(__middle, __m2, __last, __comp, __len12, __len22, __buff, __buff_size);
+// _VSTD::__inplace_merge<_Compare>(__first, __m1, __middle, __comp, __len11, __len21, __buff, __buff_size);
+ __last = __middle;
+ __middle = __m1;
+ __len1 = __len11;
+ __len2 = __len21;
+ }
+ }
+}
+
+template <class _BidirectionalIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last,
+ _Compare __comp)
+{
+ typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type;
+ typedef typename iterator_traits<_BidirectionalIterator>::difference_type difference_type;
+ difference_type __len1 = _VSTD::distance(__first, __middle);
+ difference_type __len2 = _VSTD::distance(__middle, __last);
+ difference_type __buf_size = _VSTD::min(__len1, __len2);
+ pair<value_type*, ptrdiff_t> __buf = _VSTD::get_temporary_buffer<value_type>(__buf_size);
+ unique_ptr<value_type, __return_temporary_buffer> __h(__buf.first);
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__inplace_merge<_Comp_ref>(__first, __middle, __last, __comp, __len1, __len2,
+ __buf.first, __buf.second);
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+inplace_merge(_BidirectionalIterator __first, _BidirectionalIterator __middle, _BidirectionalIterator __last)
+{
+ _VSTD::inplace_merge(__first, __middle, __last,
+ __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
+}
+
+// stable_sort
+
+template <class _Compare, class _InputIterator1, class _InputIterator2>
+void
+__merge_move_construct(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2,
+ typename iterator_traits<_InputIterator1>::value_type* __result, _Compare __comp)
+{
+ typedef typename iterator_traits<_InputIterator1>::value_type value_type;
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h(__result, __d);
+ for (; true; ++__result)
+ {
+ if (__first1 == __last1)
+ {
+ for (; __first2 != __last2; ++__first2, ++__result, (void)__d.template __incr<value_type>())
+ ::new ((void*)__result) value_type(_VSTD::move(*__first2));
+ __h.release();
+ return;
+ }
+ if (__first2 == __last2)
+ {
+ for (; __first1 != __last1; ++__first1, ++__result, (void)__d.template __incr<value_type>())
+ ::new ((void*)__result) value_type(_VSTD::move(*__first1));
+ __h.release();
+ return;
+ }
+ if (__comp(*__first2, *__first1))
+ {
+ ::new ((void*)__result) value_type(_VSTD::move(*__first2));
+ __d.template __incr<value_type>();
+ ++__first2;
+ }
+ else
+ {
+ ::new ((void*)__result) value_type(_VSTD::move(*__first1));
+ __d.template __incr<value_type>();
+ ++__first1;
+ }
+ }
+}
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+void
+__merge_move_assign(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2,
+ _OutputIterator __result, _Compare __comp)
+{
+ for (; __first1 != __last1; ++__result)
+ {
+ if (__first2 == __last2)
+ {
+ for (; __first1 != __last1; ++__first1, (void) ++__result)
+ *__result = _VSTD::move(*__first1);
+ return;
+ }
+ if (__comp(*__first2, *__first1))
+ {
+ *__result = _VSTD::move(*__first2);
+ ++__first2;
+ }
+ else
+ {
+ *__result = _VSTD::move(*__first1);
+ ++__first1;
+ }
+ }
+ for (; __first2 != __last2; ++__first2, (void) ++__result)
+ *__result = _VSTD::move(*__first2);
+}
+
+template <class _Compare, class _RandomAccessIterator>
+void
+__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size);
+
+template <class _Compare, class _RandomAccessIterator>
+void
+__stable_sort_move(_RandomAccessIterator __first1, _RandomAccessIterator __last1, _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ typename iterator_traits<_RandomAccessIterator>::value_type* __first2)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ switch (__len)
+ {
+ case 0:
+ return;
+ case 1:
+ ::new ((void*)__first2) value_type(_VSTD::move(*__first1));
+ return;
+ case 2:
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h2(__first2, __d);
+ if (__comp(*--__last1, *__first1))
+ {
+ ::new ((void*)__first2) value_type(_VSTD::move(*__last1));
+ __d.template __incr<value_type>();
+ ++__first2;
+ ::new ((void*)__first2) value_type(_VSTD::move(*__first1));
+ }
+ else
+ {
+ ::new ((void*)__first2) value_type(_VSTD::move(*__first1));
+ __d.template __incr<value_type>();
+ ++__first2;
+ ::new ((void*)__first2) value_type(_VSTD::move(*__last1));
+ }
+ __h2.release();
+ return;
+ }
+ if (__len <= 8)
+ {
+ _VSTD::__insertion_sort_move<_Compare>(__first1, __last1, __first2, __comp);
+ return;
+ }
+ typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
+ _RandomAccessIterator __m = __first1 + __l2;
+ _VSTD::__stable_sort<_Compare>(__first1, __m, __comp, __l2, __first2, __l2);
+ _VSTD::__stable_sort<_Compare>(__m, __last1, __comp, __len - __l2, __first2 + __l2, __len - __l2);
+ _VSTD::__merge_move_construct<_Compare>(__first1, __m, __m, __last1, __first2, __comp);
+}
+
+template <class _Tp>
+struct __stable_sort_switch
+{
+ static const unsigned value = 128*is_trivially_copy_assignable<_Tp>::value;
+};
+
+template <class _Compare, class _RandomAccessIterator>
+void
+__stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ typename iterator_traits<_RandomAccessIterator>::value_type* __buff, ptrdiff_t __buff_size)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ switch (__len)
+ {
+ case 0:
+ case 1:
+ return;
+ case 2:
+ if (__comp(*--__last, *__first))
+ swap(*__first, *__last);
+ return;
+ }
+ if (__len <= static_cast<difference_type>(__stable_sort_switch<value_type>::value))
+ {
+ _VSTD::__insertion_sort<_Compare>(__first, __last, __comp);
+ return;
+ }
+ typename iterator_traits<_RandomAccessIterator>::difference_type __l2 = __len / 2;
+ _RandomAccessIterator __m = __first + __l2;
+ if (__len <= __buff_size)
+ {
+ __destruct_n __d(0);
+ unique_ptr<value_type, __destruct_n&> __h2(__buff, __d);
+ _VSTD::__stable_sort_move<_Compare>(__first, __m, __comp, __l2, __buff);
+ __d.__set(__l2, (value_type*)nullptr);
+ _VSTD::__stable_sort_move<_Compare>(__m, __last, __comp, __len - __l2, __buff + __l2);
+ __d.__set(__len, (value_type*)nullptr);
+ _VSTD::__merge_move_assign<_Compare>(__buff, __buff + __l2, __buff + __l2, __buff + __len, __first, __comp);
+// _VSTD::__merge<_Compare>(move_iterator<value_type*>(__buff),
+// move_iterator<value_type*>(__buff + __l2),
+// move_iterator<_RandomAccessIterator>(__buff + __l2),
+// move_iterator<_RandomAccessIterator>(__buff + __len),
+// __first, __comp);
+ return;
+ }
+ _VSTD::__stable_sort<_Compare>(__first, __m, __comp, __l2, __buff, __buff_size);
+ _VSTD::__stable_sort<_Compare>(__m, __last, __comp, __len - __l2, __buff, __buff_size);
+ _VSTD::__inplace_merge<_Compare>(__first, __m, __last, __comp, __l2, __len - __l2, __buff, __buff_size);
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __len = __last - __first;
+ pair<value_type*, ptrdiff_t> __buf(0, 0);
+ unique_ptr<value_type, __return_temporary_buffer> __h;
+ if (__len > static_cast<difference_type>(__stable_sort_switch<value_type>::value))
+ {
+ __buf = _VSTD::get_temporary_buffer<value_type>(__len);
+ __h.reset(__buf.first);
+ }
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__stable_sort<_Comp_ref>(__first, __last, __comp, __len, __buf.first, __buf.second);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ _VSTD::stable_sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// is_heap_until
+
+template <class _RandomAccessIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT _LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
+is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __len = __last - __first;
+ difference_type __p = 0;
+ difference_type __c = 1;
+ _RandomAccessIterator __pp = __first;
+ while (__c < __len)
+ {
+ _RandomAccessIterator __cp = __first + __c;
+ if (__comp(*__pp, *__cp))
+ return __cp;
+ ++__c;
+ ++__cp;
+ if (__c == __len)
+ return __last;
+ if (__comp(*__pp, *__cp))
+ return __cp;
+ ++__p;
+ ++__pp;
+ __c = 2 * __p + 1;
+ }
+ return __last;
+}
+
+template<class _RandomAccessIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_RandomAccessIterator
+is_heap_until(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ return _VSTD::is_heap_until(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// is_heap
+
+template <class _RandomAccessIterator, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ return _VSTD::is_heap_until(__first, __last, __comp) == __last;
+}
+
+template<class _RandomAccessIterator>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ return _VSTD::is_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// push_heap
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 void
+__sift_up(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ if (__len > 1)
+ {
+ __len = (__len - 2) / 2;
+ _RandomAccessIterator __ptr = __first + __len;
+ if (__comp(*__ptr, *--__last))
+ {
+ value_type __t(_VSTD::move(*__last));
+ do
+ {
+ *__last = _VSTD::move(*__ptr);
+ __last = __ptr;
+ if (__len == 0)
+ break;
+ __len = (__len - 1) / 2;
+ __ptr = __first + __len;
+ } while (__comp(*__ptr, __t));
+ *__last = _VSTD::move(__t);
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__sift_up<_Comp_ref>(__first, __last, __comp, __last - __first);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+push_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ _VSTD::push_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// pop_heap
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 void
+__sift_down(_RandomAccessIterator __first, _RandomAccessIterator /*__last*/,
+ _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len,
+ _RandomAccessIterator __start)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type;
+ // left-child of __start is at 2 * __start + 1
+ // right-child of __start is at 2 * __start + 2
+ difference_type __child = __start - __first;
+
+ if (__len < 2 || (__len - 2) / 2 < __child)
+ return;
+
+ __child = 2 * __child + 1;
+ _RandomAccessIterator __child_i = __first + __child;
+
+ if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
+ // right-child exists and is greater than left-child
+ ++__child_i;
+ ++__child;
+ }
+
+ // check if we are in heap-order
+ if (__comp(*__child_i, *__start))
+ // we are, __start is larger than it's largest child
+ return;
+
+ value_type __top(_VSTD::move(*__start));
+ do
+ {
+ // we are not in heap-order, swap the parent with its largest child
+ *__start = _VSTD::move(*__child_i);
+ __start = __child_i;
+
+ if ((__len - 2) / 2 < __child)
+ break;
+
+ // recompute the child based off of the updated parent
+ __child = 2 * __child + 1;
+ __child_i = __first + __child;
+
+ if ((__child + 1) < __len && __comp(*__child_i, *(__child_i + 1))) {
+ // right-child exists and is greater than left-child
+ ++__child_i;
+ ++__child;
+ }
+
+ // check if we are in heap-order
+ } while (!__comp(*__child_i, __top));
+ *__start = _VSTD::move(__top);
+}
+
+template <class _Compare, class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+__pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp,
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len)
+{
+ if (__len > 1)
+ {
+ swap(*__first, *--__last);
+ _VSTD::__sift_down<_Compare>(__first, __last, __comp, __len - 1, __first);
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__pop_heap<_Comp_ref>(__first, __last, __comp, __last - __first);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ _VSTD::pop_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// make_heap
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 void
+__make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ difference_type __n = __last - __first;
+ if (__n > 1)
+ {
+ // start from the first parent, there is no need to consider children
+ for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start)
+ {
+ _VSTD::__sift_down<_Compare>(__first, __last, __comp, __n, __first + __start);
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__make_heap<_Comp_ref>(__first, __last, __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ _VSTD::make_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// sort_heap
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 void
+__sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ for (difference_type __n = __last - __first; __n > 1; --__last, (void) --__n)
+ _VSTD::__pop_heap<_Compare>(__first, __last, __comp, __n);
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__sort_heap<_Comp_ref>(__first, __last, __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ _VSTD::sort_heap(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// partial_sort
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 void
+__partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
+ _Compare __comp)
+{
+ _VSTD::__make_heap<_Compare>(__first, __middle, __comp);
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len = __middle - __first;
+ for (_RandomAccessIterator __i = __middle; __i != __last; ++__i)
+ {
+ if (__comp(*__i, *__first))
+ {
+ swap(*__i, *__first);
+ _VSTD::__sift_down<_Compare>(__first, __middle, __comp, __len, __first);
+ }
+ }
+ _VSTD::__sort_heap<_Compare>(__first, __middle, __comp);
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last,
+ _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__partial_sort<_Comp_ref>(__first, __middle, __last, __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+partial_sort(_RandomAccessIterator __first, _RandomAccessIterator __middle, _RandomAccessIterator __last)
+{
+ _VSTD::partial_sort(__first, __middle, __last,
+ __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// partial_sort_copy
+
+template <class _Compare, class _InputIterator, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _RandomAccessIterator
+__partial_sort_copy(_InputIterator __first, _InputIterator __last,
+ _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
+{
+ _RandomAccessIterator __r = __result_first;
+ if (__r != __result_last)
+ {
+ for (; __first != __last && __r != __result_last; ++__first, (void) ++__r)
+ *__r = *__first;
+ _VSTD::__make_heap<_Compare>(__result_first, __r, __comp);
+ typename iterator_traits<_RandomAccessIterator>::difference_type __len = __r - __result_first;
+ for (; __first != __last; ++__first)
+ if (__comp(*__first, *__result_first))
+ {
+ *__result_first = *__first;
+ _VSTD::__sift_down<_Compare>(__result_first, __r, __comp, __len, __result_first);
+ }
+ _VSTD::__sort_heap<_Compare>(__result_first, __r, __comp);
+ }
+ return __r;
+}
+
+template <class _InputIterator, class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_RandomAccessIterator
+partial_sort_copy(_InputIterator __first, _InputIterator __last,
+ _RandomAccessIterator __result_first, _RandomAccessIterator __result_last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__partial_sort_copy<_Comp_ref>(__first, __last, __result_first, __result_last, __comp);
+}
+
+template <class _InputIterator, class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_RandomAccessIterator
+partial_sort_copy(_InputIterator __first, _InputIterator __last,
+ _RandomAccessIterator __result_first, _RandomAccessIterator __result_last)
+{
+ return _VSTD::partial_sort_copy(__first, __last, __result_first, __result_last,
+ __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// nth_element
+
+template<class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 bool
+__nth_element_find_guard(_RandomAccessIterator& __i, _RandomAccessIterator& __j,
+ _RandomAccessIterator __m, _Compare __comp)
+{
+ // manually guard downward moving __j against __i
+ while (true) {
+ if (__i == --__j) {
+ return false;
+ }
+ if (__comp(*__j, *__m)) {
+ return true; // found guard for downward moving __j, now use unguarded partition
+ }
+ }
+}
+
+template <class _Compare, class _RandomAccessIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 void
+__nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
+{
+ // _Compare is known to be a reference type
+ typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
+ const difference_type __limit = 7;
+ while (true)
+ {
+ if (__nth == __last)
+ return;
+ difference_type __len = __last - __first;
+ switch (__len)
+ {
+ case 0:
+ case 1:
+ return;
+ case 2:
+ if (__comp(*--__last, *__first))
+ swap(*__first, *__last);
+ return;
+ case 3:
+ {
+ _RandomAccessIterator __m = __first;
+ _VSTD::__sort3<_Compare>(__first, ++__m, --__last, __comp);
+ return;
+ }
+ }
+ if (__len <= __limit)
+ {
+ _VSTD::__selection_sort<_Compare>(__first, __last, __comp);
+ return;
+ }
+ // __len > __limit >= 3
+ _RandomAccessIterator __m = __first + __len/2;
+ _RandomAccessIterator __lm1 = __last;
+ unsigned __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, --__lm1, __comp);
+ // *__m is median
+ // partition [__first, __m) < *__m and *__m <= [__m, __last)
+ // (this inhibits tossing elements equivalent to __m around unnecessarily)
+ _RandomAccessIterator __i = __first;
+ _RandomAccessIterator __j = __lm1;
+ // j points beyond range to be tested, *__lm1 is known to be <= *__m
+ // The search going up is known to be guarded but the search coming down isn't.
+ // Prime the downward search with a guard.
+ if (!__comp(*__i, *__m)) // if *__first == *__m
+ {
+ // *__first == *__m, *__first doesn't go in first part
+ if (_VSTD::__nth_element_find_guard<_Compare>(__i, __j, __m, __comp)) {
+ swap(*__i, *__j);
+ ++__n_swaps;
+ } else {
+ // *__first == *__m, *__m <= all other elements
+ // Partition instead into [__first, __i) == *__first and *__first < [__i, __last)
+ ++__i; // __first + 1
+ __j = __last;
+ if (!__comp(*__first, *--__j)) { // we need a guard if *__first == *(__last-1)
+ while (true) {
+ if (__i == __j) {
+ return; // [__first, __last) all equivalent elements
+ } else if (__comp(*__first, *__i)) {
+ swap(*__i, *__j);
+ ++__n_swaps;
+ ++__i;
+ break;
+ }
+ ++__i;
+ }
+ }
+ // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1
+ if (__i == __j) {
+ return;
+ }
+ while (true) {
+ while (!__comp(*__first, *__i))
+ ++__i;
+ while (__comp(*__first, *--__j))
+ ;
+ if (__i >= __j)
+ break;
+ swap(*__i, *__j);
+ ++__n_swaps;
+ ++__i;
+ }
+ // [__first, __i) == *__first and *__first < [__i, __last)
+ // The first part is sorted,
+ if (__nth < __i) {
+ return;
+ }
+ // __nth_element the second part
+ // _VSTD::__nth_element<_Compare>(__i, __nth, __last, __comp);
+ __first = __i;
+ continue;
+ }
+ }
+ ++__i;
+ // j points beyond range to be tested, *__lm1 is known to be <= *__m
+ // if not yet partitioned...
+ if (__i < __j)
+ {
+ // known that *(__i - 1) < *__m
+ while (true)
+ {
+ // __m still guards upward moving __i
+ while (__comp(*__i, *__m))
+ ++__i;
+ // It is now known that a guard exists for downward moving __j
+ while (!__comp(*--__j, *__m))
+ ;
+ if (__i >= __j)
+ break;
+ swap(*__i, *__j);
+ ++__n_swaps;
+ // It is known that __m != __j
+ // If __m just moved, follow it
+ if (__m == __i)
+ __m = __j;
+ ++__i;
+ }
+ }
+ // [__first, __i) < *__m and *__m <= [__i, __last)
+ if (__i != __m && __comp(*__m, *__i))
+ {
+ swap(*__i, *__m);
+ ++__n_swaps;
+ }
+ // [__first, __i) < *__i and *__i <= [__i+1, __last)
+ if (__nth == __i)
+ return;
+ if (__n_swaps == 0)
+ {
+ // We were given a perfectly partitioned sequence. Coincidence?
+ if (__nth < __i)
+ {
+ // Check for [__first, __i) already sorted
+ __j = __m = __first;
+ while (true) {
+ if (++__j == __i) {
+ // [__first, __i) sorted
+ return;
+ }
+ if (__comp(*__j, *__m)) {
+ // not yet sorted, so sort
+ break;
+ }
+ __m = __j;
+ }
+ }
+ else
+ {
+ // Check for [__i, __last) already sorted
+ __j = __m = __i;
+ while (true) {
+ if (++__j == __last) {
+ // [__i, __last) sorted
+ return;
+ }
+ if (__comp(*__j, *__m)) {
+ // not yet sorted, so sort
+ break;
+ }
+ __m = __j;
+ }
+ }
+ }
+ // __nth_element on range containing __nth
+ if (__nth < __i)
+ {
+ // _VSTD::__nth_element<_Compare>(__first, __nth, __i, __comp);
+ __last = __i;
+ }
+ else
+ {
+ // _VSTD::__nth_element<_Compare>(__i+1, __nth, __last, __comp);
+ __first = ++__i;
+ }
+ }
+}
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ _VSTD::__nth_element<_Comp_ref>(__first, __nth, __last, __comp);
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, _RandomAccessIterator __last)
+{
+ _VSTD::nth_element(__first, __nth, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// sort
+
+template <class _RandomAccessIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ if (__libcpp_is_constant_evaluated()) {
+ _VSTD::__partial_sort<_Comp_ref>(__first, __last, __last, _Comp_ref(__comp));
+ } else {
+ _VSTD::__sort<_Comp_ref>(_VSTD::__unwrap_iter(__first), _VSTD::__unwrap_iter(__last), _Comp_ref(__comp));
+ }
+}
+
+template <class _RandomAccessIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+void
+sort(_RandomAccessIterator __first, _RandomAccessIterator __last)
+{
+ _VSTD::sort(__first, __last, __less<typename iterator_traits<_RandomAccessIterator>::value_type>());
+}
+
+// includes
+
+template <class _Compare, class _InputIterator1, class _InputIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+__includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
+ _Compare __comp)
+{
+ for (; __first2 != __last2; ++__first1)
+ {
+ if (__first1 == __last1 || __comp(*__first2, *__first1))
+ return false;
+ if (!__comp(*__first1, *__first2))
+ ++__first2;
+ }
+ return true;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
+ _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__includes<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+includes(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2)
+{
+ return _VSTD::includes(__first1, __last1, __first2, __last2,
+ __less<typename iterator_traits<_InputIterator1>::value_type,
+ typename iterator_traits<_InputIterator2>::value_type>());
+}
+
+// set_union
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+__set_union(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ for (; __first1 != __last1; ++__result)
+ {
+ if (__first2 == __last2)
+ return _VSTD::copy(__first1, __last1, __result);
+ if (__comp(*__first2, *__first1))
+ {
+ *__result = *__first2;
+ ++__first2;
+ }
+ else
+ {
+ if (!__comp(*__first1, *__first2))
+ ++__first2;
+ *__result = *__first1;
+ ++__first1;
+ }
+ }
+ return _VSTD::copy(__first2, __last2, __result);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_union(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__set_union<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_union(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
+{
+ return _VSTD::set_union(__first1, __last1, __first2, __last2, __result,
+ __less<typename iterator_traits<_InputIterator1>::value_type,
+ typename iterator_traits<_InputIterator2>::value_type>());
+}
+
+// set_intersection
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+__set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ while (__first1 != __last1 && __first2 != __last2)
+ {
+ if (__comp(*__first1, *__first2))
+ ++__first1;
+ else
+ {
+ if (!__comp(*__first2, *__first1))
+ {
+ *__result = *__first1;
+ ++__result;
+ ++__first1;
+ }
+ ++__first2;
+ }
+ }
+ return __result;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__set_intersection<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
+{
+ return _VSTD::set_intersection(__first1, __last1, __first2, __last2, __result,
+ __less<typename iterator_traits<_InputIterator1>::value_type,
+ typename iterator_traits<_InputIterator2>::value_type>());
+}
+
+// set_difference
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+__set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ while (__first1 != __last1)
+ {
+ if (__first2 == __last2)
+ return _VSTD::copy(__first1, __last1, __result);
+ if (__comp(*__first1, *__first2))
+ {
+ *__result = *__first1;
+ ++__result;
+ ++__first1;
+ }
+ else
+ {
+ if (!__comp(*__first2, *__first1))
+ ++__first1;
+ ++__first2;
+ }
+ }
+ return __result;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__set_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
+{
+ return _VSTD::set_difference(__first1, __last1, __first2, __last2, __result,
+ __less<typename iterator_traits<_InputIterator1>::value_type,
+ typename iterator_traits<_InputIterator2>::value_type>());
+}
+
+// set_symmetric_difference
+
+template <class _Compare, class _InputIterator1, class _InputIterator2, class _OutputIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _OutputIterator
+__set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ while (__first1 != __last1)
+ {
+ if (__first2 == __last2)
+ return _VSTD::copy(__first1, __last1, __result);
+ if (__comp(*__first1, *__first2))
+ {
+ *__result = *__first1;
+ ++__result;
+ ++__first1;
+ }
+ else
+ {
+ if (__comp(*__first2, *__first1))
+ {
+ *__result = *__first2;
+ ++__result;
+ }
+ else
+ ++__first1;
+ ++__first2;
+ }
+ }
+ return _VSTD::copy(__first2, __last2, __result);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__set_symmetric_difference<_Comp_ref>(__first1, __last1, __first2, __last2, __result, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2, class _OutputIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+_OutputIterator
+set_symmetric_difference(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _OutputIterator __result)
+{
+ return _VSTD::set_symmetric_difference(__first1, __last1, __first2, __last2, __result,
+ __less<typename iterator_traits<_InputIterator1>::value_type,
+ typename iterator_traits<_InputIterator2>::value_type>());
+}
+
+// lexicographical_compare
+
+template <class _Compare, class _InputIterator1, class _InputIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+__lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
+{
+ for (; __first2 != __last2; ++__first1, (void) ++__first2)
+ {
+ if (__first1 == __last1 || __comp(*__first1, *__first2))
+ return true;
+ if (__comp(*__first2, *__first1))
+ return false;
+ }
+ return false;
+}
+
+template <class _InputIterator1, class _InputIterator2, class _Compare>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__lexicographical_compare<_Comp_ref>(__first1, __last1, __first2, __last2, __comp);
+}
+
+template <class _InputIterator1, class _InputIterator2>
+_LIBCPP_NODISCARD_EXT inline
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
+ _InputIterator2 __first2, _InputIterator2 __last2)
+{
+ return _VSTD::lexicographical_compare(__first1, __last1, __first2, __last2,
+ __less<typename iterator_traits<_InputIterator1>::value_type,
+ typename iterator_traits<_InputIterator2>::value_type>());
+}
+
+// next_permutation
+
+template <class _Compare, class _BidirectionalIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+__next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
+{
+ _BidirectionalIterator __i = __last;
+ if (__first == __last || __first == --__i)
+ return false;
+ while (true)
+ {
+ _BidirectionalIterator __ip1 = __i;
+ if (__comp(*--__i, *__ip1))
+ {
+ _BidirectionalIterator __j = __last;
+ while (!__comp(*__i, *--__j))
+ ;
+ swap(*__i, *__j);
+ _VSTD::reverse(__ip1, __last);
+ return true;
+ }
+ if (__i == __first)
+ {
+ _VSTD::reverse(__first, __last);
+ return false;
+ }
+ }
+}
+
+template <class _BidirectionalIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__next_permutation<_Comp_ref>(__first, __last, __comp);
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+next_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
+{
+ return _VSTD::next_permutation(__first, __last,
+ __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
+}
+
+// prev_permutation
+
+template <class _Compare, class _BidirectionalIterator>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
+__prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
+{
+ _BidirectionalIterator __i = __last;
+ if (__first == __last || __first == --__i)
+ return false;
+ while (true)
+ {
+ _BidirectionalIterator __ip1 = __i;
+ if (__comp(*__ip1, *--__i))
+ {
+ _BidirectionalIterator __j = __last;
+ while (!__comp(*--__j, *__i))
+ ;
+ swap(*__i, *__j);
+ _VSTD::reverse(__ip1, __last);
+ return true;
+ }
+ if (__i == __first)
+ {
+ _VSTD::reverse(__first, __last);
+ return false;
+ }
+ }
+}
+
+template <class _BidirectionalIterator, class _Compare>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp)
+{
+ typedef typename __comp_ref_type<_Compare>::type _Comp_ref;
+ return _VSTD::__prev_permutation<_Comp_ref>(__first, __last, __comp);
+}
+
+template <class _BidirectionalIterator>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
+bool
+prev_permutation(_BidirectionalIterator __first, _BidirectionalIterator __last)
+{
+ return _VSTD::prev_permutation(__first, __last,
+ __less<typename iterator_traits<_BidirectionalIterator>::value_type>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
_LIBCPP_POP_MACROS
#if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17