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+/*
+ Copyright (c) Alexander Zaitsev <zamazan4ik@gmail.com>, 2017
+
+ Distributed under the Boost Software License, Version 1.0. (See
+ accompanying file LICENSE_1_0.txt or copy at
+ http://www.boost.org/LICENSE_1_0.txt)
+
+ See http://www.boost.org/ for latest version.
+
+
+ Based on https://blogs.msdn.microsoft.com/oldnewthing/20170104-00/?p=95115
+*/
+
+/// \file apply_permutation.hpp
+/// \brief Apply permutation to a sequence.
+/// \author Alexander Zaitsev
+
+#ifndef BOOST_ALGORITHM_APPLY_PERMUTATION_HPP
+#define BOOST_ALGORITHM_APPLY_PERMUTATION_HPP
+
+#include <algorithm>
+#include <type_traits>
+
+#include <boost/range/begin.hpp>
+#include <boost/range/end.hpp>
+
+namespace boost { namespace algorithm
+{
+
+/// \fn apply_permutation ( RandomAccessIterator1 item_begin, RandomAccessIterator1 item_end, RandomAccessIterator2 ind_begin )
+/// \brief Reorder item sequence with index sequence order
+///
+/// \param item_begin The start of the item sequence
+/// \param item_end One past the end of the item sequence
+/// \param ind_begin The start of the index sequence.
+///
+/// \note Item sequence size should be equal to index size. Otherwise behavior is undefined.
+/// Complexity: O(N).
+template<typename RandomAccessIterator1, typename RandomAccessIterator2>
+void
+apply_permutation(RandomAccessIterator1 item_begin, RandomAccessIterator1 item_end,
+ RandomAccessIterator2 ind_begin, RandomAccessIterator2 ind_end)
+{
+ typedef typename std::iterator_traits<RandomAccessIterator1>::difference_type Diff;
+ typedef typename std::iterator_traits<RandomAccessIterator2>::difference_type Index;
+ using std::swap;
+ Diff size = std::distance(item_begin, item_end);
+ for (Diff i = 0; i < size; i++)
+ {
+ Diff current = i;
+ while (i != ind_begin[current])
+ {
+ Index next = ind_begin[current];
+ swap(item_begin[current], item_begin[next]);
+ ind_begin[current] = current;
+ current = next;
+ }
+ ind_begin[current] = current;
+ }
+}
+
+/// \fn apply_reverse_permutation ( RandomAccessIterator1 item_begin, RandomAccessIterator1 item_end, RandomAccessIterator2 ind_begin )
+/// \brief Reorder item sequence with index sequence order
+///
+/// \param item_begin The start of the item sequence
+/// \param item_end One past the end of the item sequence
+/// \param ind_begin The start of the index sequence.
+///
+/// \note Item sequence size should be equal to index size. Otherwise behavior is undefined.
+/// Complexity: O(N).
+template<typename RandomAccessIterator1, typename RandomAccessIterator2>
+void
+apply_reverse_permutation(
+ RandomAccessIterator1 item_begin,
+ RandomAccessIterator1 item_end,
+ RandomAccessIterator2 ind_begin,
+ RandomAccessIterator2 ind_end)
+{
+ typedef typename std::iterator_traits<RandomAccessIterator2>::difference_type Diff;
+ using std::swap;
+ Diff length = std::distance(item_begin, item_end);
+ for (Diff i = 0; i < length; i++)
+ {
+ while (i != ind_begin[i])
+ {
+ Diff next = ind_begin[i];
+ swap(item_begin[i], item_begin[next]);
+ swap(ind_begin[i], ind_begin[next]);
+ }
+ }
+}
+
+/// \fn apply_permutation ( Range1 item_range, Range2 ind_range )
+/// \brief Reorder item sequence with index sequence order
+///
+/// \param item_range The item sequence
+/// \param ind_range The index sequence
+///
+/// \note Item sequence size should be equal to index size. Otherwise behavior is undefined.
+/// Complexity: O(N).
+template<typename Range1, typename Range2>
+void
+apply_permutation(Range1& item_range, Range2& ind_range)
+{
+ apply_permutation(boost::begin(item_range), boost::end(item_range),
+ boost::begin(ind_range), boost::end(ind_range));
+}
+
+/// \fn apply_reverse_permutation ( Range1 item_range, Range2 ind_range )
+/// \brief Reorder item sequence with index sequence order
+///
+/// \param item_range The item sequence
+/// \param ind_range The index sequence
+///
+/// \note Item sequence size should be equal to index size. Otherwise behavior is undefined.
+/// Complexity: O(N).
+template<typename Range1, typename Range2>
+void
+apply_reverse_permutation(Range1& item_range, Range2& ind_range)
+{
+ apply_reverse_permutation(boost::begin(item_range), boost::end(item_range),
+ boost::begin(ind_range), boost::end(ind_range));
+}
+
+}}
+#endif //BOOST_ALGORITHM_APPLY_PERMUTATION_HPP