ceph/src/boost/libs/range/include/boost/range/algorithm/nth_element.hpp

   1 //  Copyright Neil Groves 2009. Use, modification and
   2 //  distribution is subject to the Boost Software License, Version
   3 //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
   4 //  http://www.boost.org/LICENSE_1_0.txt)
   5 //
   6 //
   7 // For more information, see http://www.boost.org/libs/range/
   8 //
   9 #ifndef BOOST_RANGE_ALGORITHM_NTH_ELEMENT_HPP_INCLUDED
  10 #define BOOST_RANGE_ALGORITHM_NTH_ELEMENT_HPP_INCLUDED
  11
  12 #include <boost/concept_check.hpp>
  13 #include <boost/range/begin.hpp>
  14 #include <boost/range/end.hpp>
  15 #include <boost/range/concepts.hpp>
  16 #include <algorithm>
  17
  18 namespace boost
  19 {
  20     namespace range
  21     {
  22
  23 /// \brief template function nth_element
  24 ///
  25 /// range-based version of the nth_element std algorithm
  26 ///
  27 /// \pre RandomAccessRange is a model of the RandomAccessRangeConcept
  28 /// \pre BinaryPredicate is a model of the BinaryPredicateConcept
  29 template<class RandomAccessRange>
  30 inline RandomAccessRange& nth_element(RandomAccessRange& rng,
  31     BOOST_DEDUCED_TYPENAME range_iterator<RandomAccessRange>::type nth)
  32 {
  33     BOOST_RANGE_CONCEPT_ASSERT(( RandomAccessRangeConcept<RandomAccessRange> ));
  34     std::nth_element(boost::begin(rng), nth, boost::end(rng));
  35     return rng;
  36 }
  37
  38 /// \overload
  39 template<class RandomAccessRange>
  40 inline const RandomAccessRange& nth_element(const RandomAccessRange& rng,
  41     BOOST_DEDUCED_TYPENAME range_iterator<const RandomAccessRange>::type nth)
  42 {
  43     BOOST_RANGE_CONCEPT_ASSERT(( RandomAccessRangeConcept<const RandomAccessRange> ));
  44     std::nth_element(boost::begin(rng), nth, boost::end(rng));
  45     return rng;
  46 }
  47
  48 /// \overload
  49 template<class RandomAccessRange, class BinaryPredicate>
  50 inline RandomAccessRange& nth_element(RandomAccessRange& rng,
  51     BOOST_DEDUCED_TYPENAME range_iterator<RandomAccessRange>::type nth,
  52     BinaryPredicate sort_pred)
  53 {
  54     BOOST_RANGE_CONCEPT_ASSERT(( RandomAccessRangeConcept<RandomAccessRange> ));
  55     std::nth_element(boost::begin(rng), nth, boost::end(rng), sort_pred);
  56     return rng;
  57 }
  58
  59 /// \overload
  60 template<class RandomAccessRange, class BinaryPredicate>
  61 inline const RandomAccessRange& nth_element(const RandomAccessRange& rng,
  62     BOOST_DEDUCED_TYPENAME range_iterator<const RandomAccessRange>::type nth,
  63     BinaryPredicate sort_pred)
  64 {
  65     BOOST_RANGE_CONCEPT_ASSERT(( RandomAccessRangeConcept<const RandomAccessRange> ));
  66     std::nth_element(boost::begin(rng), nth, boost::end(rng), sort_pred);
  67     return rng;
  68 }
  69
  70     } // namespace range
  71     using range::nth_element;
  72 } // namespace boost
  73
  74 #endif // include guard