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diff --git a/contrib/llvm-project/libcxx/include/__algorithm/sample.h b/contrib/llvm-project/libcxx/include/__algorithm/sample.h
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+++ b/contrib/llvm-project/libcxx/include/__algorithm/sample.h
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+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_SAMPLE_H
+#define _LIBCPP___ALGORITHM_SAMPLE_H
+
+#include <__algorithm/iterator_operations.h>
+#include <__algorithm/min.h>
+#include <__assert>
+#include <__config>
+#include <__iterator/distance.h>
+#include <__iterator/iterator_traits.h>
+#include <__random/uniform_int_distribution.h>
+#include <__type_traits/common_type.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _AlgPolicy,
+          class _PopulationIterator,
+          class _PopulationSentinel,
+          class _SampleIterator,
+          class _Distance,
+          class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _SampleIterator __sample(
+    _PopulationIterator __first,
+    _PopulationSentinel __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 + std::min(__n, __k);
+}
+
+template <class _AlgPolicy,
+          class _PopulationIterator,
+          class _PopulationSentinel,
+          class _SampleIterator,
+          class _Distance,
+          class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _SampleIterator __sample(
+    _PopulationIterator __first,
+    _PopulationSentinel __last,
+    _SampleIterator __output_iter,
+    _Distance __n,
+    _UniformRandomNumberGenerator& __g,
+    forward_iterator_tag) {
+  _Distance __unsampled_sz = _IterOps<_AlgPolicy>::distance(__first, __last);
+  for (__n = std::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 _AlgPolicy,
+          class _PopulationIterator,
+          class _PopulationSentinel,
+          class _SampleIterator,
+          class _Distance,
+          class _UniformRandomNumberGenerator>
+_LIBCPP_HIDE_FROM_ABI _SampleIterator __sample(
+    _PopulationIterator __first,
+    _PopulationSentinel __last,
+    _SampleIterator __output_iter,
+    _Distance __n,
+    _UniformRandomNumberGenerator& __g) {
+  _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n >= 0, "N must be a positive number.");
+
+  using _PopIterCategory = typename _IterOps<_AlgPolicy>::template __iterator_category<_PopulationIterator>;
+  using _Difference      = typename _IterOps<_AlgPolicy>::template __difference_type<_PopulationIterator>;
+  using _CommonType      = typename common_type<_Distance, _Difference>::type;
+
+  return std::__sample<_AlgPolicy>(
+      std::move(__first), std::move(__last), std::move(__output_iter), _CommonType(__n), __g, _PopIterCategory());
+}
+
+#if _LIBCPP_STD_VER >= 17
+template <class _PopulationIterator, class _SampleIterator, class _Distance, class _UniformRandomNumberGenerator>
+inline _LIBCPP_HIDE_FROM_ABI _SampleIterator
+sample(_PopulationIterator __first,
+       _PopulationIterator __last,
+       _SampleIterator __output_iter,
+       _Distance __n,
+       _UniformRandomNumberGenerator&& __g) {
+  static_assert(__has_forward_iterator_category<_PopulationIterator>::value ||
+                    __has_random_access_iterator_category<_SampleIterator>::value,
+                "SampleIterator must meet the requirements of RandomAccessIterator");
+
+  return std::__sample<_ClassicAlgPolicy>(std::move(__first), std::move(__last), std::move(__output_iter), __n, __g);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_SAMPLE_H