annotate DEPENDENCIES/generic/include/boost/algorithm/cxx11/partition_point.hpp @ 133:4acb5d8d80b6 tip

Don't fail environmental check if README.md exists (but .txt and no-suffix don't)
author Chris Cannam
date Tue, 30 Jul 2019 12:25:44 +0100
parents c530137014c0
children
rev   line source
Chris@16 1 /*
Chris@16 2 Copyright (c) Marshall Clow 2011-2012.
Chris@16 3
Chris@16 4 Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16 5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16 6 */
Chris@16 7
Chris@16 8 /// \file partition_point.hpp
Chris@16 9 /// \brief Find the partition point in a sequence
Chris@16 10 /// \author Marshall Clow
Chris@16 11
Chris@16 12 #ifndef BOOST_ALGORITHM_PARTITION_POINT_HPP
Chris@16 13 #define BOOST_ALGORITHM_PARTITION_POINT_HPP
Chris@16 14
Chris@16 15 #include <algorithm> // for std::partition_point, if available
Chris@16 16
Chris@16 17 #include <boost/range/begin.hpp>
Chris@16 18 #include <boost/range/end.hpp>
Chris@16 19
Chris@16 20 namespace boost { namespace algorithm {
Chris@16 21
Chris@16 22 /// \fn partition_point ( ForwardIterator first, ForwardIterator last, Predicate p )
Chris@16 23 /// \brief Given a partitioned range, returns the partition point, i.e, the first element
Chris@16 24 /// that does not satisfy p
Chris@16 25 ///
Chris@16 26 /// \param first The start of the input sequence
Chris@16 27 /// \param last One past the end of the input sequence
Chris@16 28 /// \param p The predicate to test the values with
Chris@16 29 /// \note This function is part of the C++2011 standard library.
Chris@16 30 /// We will use the standard one if it is available,
Chris@16 31 /// otherwise we have our own implementation.
Chris@16 32 template <typename ForwardIterator, typename Predicate>
Chris@16 33 ForwardIterator partition_point ( ForwardIterator first, ForwardIterator last, Predicate p )
Chris@16 34 {
Chris@16 35 std::size_t dist = std::distance ( first, last );
Chris@16 36 while ( first != last ) {
Chris@16 37 std::size_t d2 = dist / 2;
Chris@16 38 ForwardIterator ret_val = first;
Chris@16 39 std::advance (ret_val, d2);
Chris@16 40 if (p (*ret_val)) {
Chris@16 41 first = ++ret_val;
Chris@16 42 dist -= d2 + 1;
Chris@16 43 }
Chris@16 44 else {
Chris@16 45 last = ret_val;
Chris@16 46 dist = d2;
Chris@16 47 }
Chris@16 48 }
Chris@16 49 return first;
Chris@16 50 }
Chris@16 51
Chris@16 52 /// \fn partition_point ( Range &r, Predicate p )
Chris@16 53 /// \brief Given a partitioned range, returns the partition point
Chris@16 54 ///
Chris@16 55 /// \param r The input range
Chris@16 56 /// \param p The predicate to test the values with
Chris@16 57 ///
Chris@16 58 template <typename Range, typename Predicate>
Chris@101 59 typename boost::range_iterator<Range>::type partition_point ( Range &r, Predicate p )
Chris@16 60 {
Chris@16 61 return boost::algorithm::partition_point (boost::begin(r), boost::end(r), p);
Chris@16 62 }
Chris@16 63
Chris@16 64
Chris@16 65 }}
Chris@16 66
Chris@16 67 #endif // BOOST_ALGORITHM_PARTITION_POINT_HPP