| 1 | /* |
| 2 | Copyright (c) Marshall Clow 2017. |
| 3 | |
| 4 | Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 5 | file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| 6 | */ |
| 7 | |
| 8 | /// \file transform_reduce.hpp |
| 9 | /// \brief Combine the (transformed) elements of a sequence (or two) into a single value. |
| 10 | /// \author Marshall Clow |
| 11 | |
| 12 | #ifndef BOOST_ALGORITHM_INCLUSIVE_SCAN_HPP |
| 13 | #define BOOST_ALGORITHM_INCLUSIVE_SCAN_HPP |
| 14 | |
| 15 | #include <functional> // for std::plus |
| 16 | #include <iterator> // for std::iterator_traits |
| 17 | |
| 18 | #include <boost/config.hpp> |
| 19 | #include <boost/range/begin.hpp> |
| 20 | #include <boost/range/end.hpp> |
| 21 | #include <boost/range/value_type.hpp> |
| 22 | |
| 23 | namespace boost { namespace algorithm { |
| 24 | |
| 25 | template<class InputIterator, class OutputIterator, class T, class BinaryOperation> |
| 26 | OutputIterator inclusive_scan(InputIterator first, InputIterator last, |
| 27 | OutputIterator result, BinaryOperation bOp, T init) |
| 28 | { |
| 29 | for (; first != last; ++first, (void) ++result) { |
| 30 | init = bOp(init, *first); |
| 31 | *result = init; |
| 32 | } |
| 33 | return result; |
| 34 | } |
| 35 | |
| 36 | |
| 37 | template<class InputIterator, class OutputIterator, class BinaryOperation> |
| 38 | OutputIterator inclusive_scan(InputIterator first, InputIterator last, |
| 39 | OutputIterator result, BinaryOperation bOp) |
| 40 | { |
| 41 | if (first != last) { |
| 42 | typename std::iterator_traits<InputIterator>::value_type init = *first; |
| 43 | *result++ = init; |
| 44 | if (++first != last) |
| 45 | return boost::algorithm::inclusive_scan(first, last, result, bOp, init); |
| 46 | } |
| 47 | |
| 48 | return result; |
| 49 | } |
| 50 | |
| 51 | template<class InputIterator, class OutputIterator> |
| 52 | OutputIterator inclusive_scan(InputIterator first, InputIterator last, |
| 53 | OutputIterator result) |
| 54 | { |
| 55 | typedef typename std::iterator_traits<InputIterator>::value_type VT; |
| 56 | return boost::algorithm::inclusive_scan(first, last, result, std::plus<VT>()); |
| 57 | } |
| 58 | |
| 59 | }} // namespace boost and algorithm |
| 60 | |
| 61 | #endif // BOOST_ALGORITHM_INCLUSIVE_SCAN_HPP |
| 62 | |