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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 reduce.hpp
+/// \brief Combine the elements of a sequence into a single value
+/// \author Marshall Clow
+
+#ifndef BOOST_ALGORITHM_REDUCE_HPP
+#define BOOST_ALGORITHM_REDUCE_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 T, class BinaryOperation>
+T reduce(InputIterator first, InputIterator last, T init, BinaryOperation bOp)
+{
+ ;
+ for (; first != last; ++first)
+ init = bOp(init, *first);
+ return init;
+}
+
+template<class InputIterator, class T>
+T reduce(InputIterator first, InputIterator last, T init)
+{
+ typedef typename std::iterator_traits<InputIterator>::value_type VT;
+ return reduce(first, last, init, std::plus<VT>());
+}
+
+template<class InputIterator>
+typename std::iterator_traits<InputIterator>::value_type
+reduce(InputIterator first, InputIterator last)
+{
+ return reduce(first, last,
+ typename std::iterator_traits<InputIterator>::value_type());
+}
+
+template<class Range>
+typename boost::range_value<Range>::type
+reduce(const Range &r)
+{
+ return reduce(boost::begin(r), boost::end(r));
+}
+
+// Not sure that this won't be ambiguous (1)
+template<class Range, class T>
+T reduce(const Range &r, T init)
+{
+ return reduce(boost::begin (r), boost::end (r), init);
+}
+
+
+// Not sure that this won't be ambiguous (2)
+template<class Range, class T, class BinaryOperation>
+T reduce(const Range &r, T init, BinaryOperation bOp)
+{
+ return reduce(boost::begin(r), boost::end(r), init, bOp);
+}
+
+}} // namespace boost and algorithm
+
+#endif // BOOST_ALGORITHM_REDUCE_HPP