1 //////////////////////////////////////////////////////////////////////////////
3 // (C) Copyright Ion Gaztanaga 2015-2016.
4 // Distributed under the Boost Software License, Version 1.0.
5 // (See accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt)
8 // See http://www.boost.org/libs/move for documentation.
10 //////////////////////////////////////////////////////////////////////////////
12 #ifndef BOOST_MOVE_ADAPTIVE_MERGE_HPP
13 #define BOOST_MOVE_ADAPTIVE_MERGE_HPP
15 #include <boost/move/detail/config_begin.hpp>
16 #include <boost/move/algo/detail/adaptive_sort_merge.hpp>
21 //! <b>Effects</b>: Merges two consecutive sorted ranges [first, middle) and [middle, last)
22 //! into one sorted range [first, last) according to the given comparison function comp.
23 //! The algorithm is stable (if there are equivalent elements in the original two ranges,
24 //! the elements from the first range (preserving their original order) precede the elements
25 //! from the second range (preserving their original order).
28 //! - RandIt must meet the requirements of ValueSwappable and RandomAccessIterator.
29 //! - The type of dereferenced RandIt must meet the requirements of MoveAssignable and MoveConstructible.
31 //! <b>Parameters</b>:
32 //! - first: the beginning of the first sorted range.
33 //! - middle: the end of the first sorted range and the beginning of the second
34 //! - last: the end of the second sorted range
35 //! - comp: comparison function object which returns true if the first argument is is ordered before the second.
36 //! - uninitialized, uninitialized_len: raw storage starting on "uninitialized", able to hold "uninitialized_len"
37 //! elements of type iterator_traits<RandIt>::value_type. Maximum performance is achieved when uninitialized_len
38 //! is min(std::distance(first, middle), std::distance(middle, last)).
40 //! <b>Throws</b>: If comp throws or the move constructor, move assignment or swap of the type
41 //! of dereferenced RandIt throws.
43 //! <b>Complexity</b>: Always K x O(N) comparisons and move assignments/constructors/swaps.
44 //! Constant factor for comparisons and data movement is minimized when uninitialized_len
45 //! is min(std::distance(first, middle), std::distance(middle, last)).
46 //! Pretty good enough performance is achieved when uninitialized_len is
47 //! ceil(sqrt(std::distance(first, last)))*2.
49 //! <b>Caution</b>: Experimental implementation, not production-ready.
50 template<class RandIt, class Compare>
51 void adaptive_merge( RandIt first, RandIt middle, RandIt last, Compare comp
52 , typename iterator_traits<RandIt>::value_type* uninitialized = 0
53 , std::size_t uninitialized_len = 0)
55 typedef typename iterator_traits<RandIt>::size_type size_type;
56 typedef typename iterator_traits<RandIt>::value_type value_type;
58 ::boost::movelib::detail_adaptive::adaptive_xbuf<value_type> xbuf(uninitialized, uninitialized_len);
59 ::boost::movelib::detail_adaptive::adaptive_merge_impl(first, size_type(middle - first), size_type(last - middle), comp, xbuf);
62 } //namespace movelib {
65 #include <boost/move/detail/config_end.hpp>
67 #endif //#define BOOST_MOVE_ADAPTIVE_MERGE_HPP