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+/*
+ Copyright (c) Marshall Clow 2017.
+
+ Distributed under the Boost Software License, Version 1.0. (See accompanying
+ file LICENSE10.txt or copy at http://www.boost.org/LICENSE10.txt)
+*/
+
+/// \file exclusive_scan.hpp
+/// \brief ???
+/// \author Marshall Clow
+
+#ifndef BOOST_ALGORITHM_EXCLUSIVE_SCAN_HPP
+#define BOOST_ALGORITHM_EXCLUSIVE_SCAN_HPP
+
+#include <functional> // for std::plus
+#include <iterator> // for std::iterator_traits
+
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+#include <boost/range/value_type.hpp>
+
+namespace boost { namespace algorithm {
+
+template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
+OutputIterator exclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, T init, BinaryOperation bOp)
+{
+ if (first != last)
+ {
+ T saved = init;
+ do
+ {
+ init = bOp(init, *first);
+ *result = saved;
+ saved = init;
+ ++result;
+ } while (++first != last);
+ }
+ return result;
+}
+
+template<class InputIterator, class OutputIterator, class T>
+OutputIterator exclusive_scan(InputIterator first, InputIterator last,
+ OutputIterator result, T init)
+{
+ typedef typename std::iterator_traits<InputIterator>::value_type VT;
+ return exclusive_scan(first, last, result, init, std::plus<VT>());
+}
+
+}} // namespace boost and algorithm
+
+#endif // BOOST_ALGORITHM_EXCLUSIVE_SCAN_HPP