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// Copyright (c) 2013 Kyle Lutz <>
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// See for more information.


#include <cstddef>
#include <algorithm>
#include <iterator>

namespace boost {
namespace compute {
namespace detail {

// This is a convenience function which returns the size of a range
// bounded by two iterators. This function has two differences from
// the std::distance() function: 1) the return type (size_t) is
// unsigned, and 2) the return value is always positive.
template<class Iterator>
inline size_t iterator_range_size(Iterator first, Iterator last)
    typedef typename

    difference_type difference = std::distance(first, last);

    return static_cast<size_t>(
        (std::max)(difference, static_cast<difference_type>(0))

} // end detail namespace
} // end compute namespace
} // end boost namespace