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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CXX03___ALGORITHM_COPY_N_H10#define _LIBCPP___CXX03___ALGORITHM_COPY_N_H11 12#include <__cxx03/__algorithm/copy.h>13#include <__cxx03/__config>14#include <__cxx03/__iterator/iterator_traits.h>15#include <__cxx03/__type_traits/enable_if.h>16#include <__cxx03/__utility/convert_to_integral.h>17 18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)19# pragma GCC system_header20#endif21 22_LIBCPP_BEGIN_NAMESPACE_STD23 24template <class _InputIterator,25 class _Size,26 class _OutputIterator,27 __enable_if_t<__has_input_iterator_category<_InputIterator>::value &&28 !__has_random_access_iterator_category<_InputIterator>::value,29 int> = 0>30inline _LIBCPP_HIDE_FROM_ABI _OutputIterator copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result) {31 typedef decltype(std::__convert_to_integral(__orig_n)) _IntegralSize;32 _IntegralSize __n = __orig_n;33 if (__n > 0) {34 *__result = *__first;35 ++__result;36 for (--__n; __n > 0; --__n) {37 ++__first;38 *__result = *__first;39 ++__result;40 }41 }42 return __result;43}44 45template <class _InputIterator,46 class _Size,47 class _OutputIterator,48 __enable_if_t<__has_random_access_iterator_category<_InputIterator>::value, int> = 0>49inline _LIBCPP_HIDE_FROM_ABI _OutputIterator copy_n(_InputIterator __first, _Size __orig_n, _OutputIterator __result) {50 typedef typename iterator_traits<_InputIterator>::difference_type difference_type;51 typedef decltype(std::__convert_to_integral(__orig_n)) _IntegralSize;52 _IntegralSize __n = __orig_n;53 return std::copy(__first, __first + difference_type(__n), __result);54}55 56_LIBCPP_END_NAMESPACE_STD57 58#endif // _LIBCPP___CXX03___ALGORITHM_COPY_N_H59