45 lines
1.5 KiB
C++
45 lines
1.5 KiB
C++
/*
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Copyright (c) Marshall Clow 2011-2012.
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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*/
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/// \file copy_n.hpp
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/// \brief Copy n items from one sequence to another
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/// \author Marshall Clow
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#ifndef BOOST_ALGORITHM_COPY_N_HPP
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#define BOOST_ALGORITHM_COPY_N_HPP
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#include <algorithm> // for std::copy_n, if available
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namespace boost { namespace algorithm {
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#if __cplusplus >= 201103L
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// Use the C++11 versions of copy_n if it is available
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using std::copy_n; // Section 25.3.1
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#else
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/// \fn copy_n ( InputIterator first, Size n, OutputIterator result )
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/// \brief Copies exactly n (n > 0) elements from the range starting at first to
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/// the range starting at result.
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/// \return The updated output iterator
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///
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/// \param first The start of the input sequence
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/// \param n The number of elements to copy
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/// \param result An output iterator to write the results into
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/// \note This function is part of the C++2011 standard library.
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/// We will use the standard one if it is available,
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/// otherwise we have our own implementation.
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template <typename InputIterator, typename Size, typename OutputIterator>
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OutputIterator copy_n ( InputIterator first, Size n, OutputIterator result )
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{
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for ( ; n > 0; --n, ++first, ++result )
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*result = *first;
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return result;
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}
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#endif
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}} // namespace boost and algorithm
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#endif // BOOST_ALGORITHM_COPY_IF_HPP
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