xref: /llvm-project/libcxx/include/__cxx03/__algorithm/make_heap.h (revision ce7771902dc50d900de639d499a60486b83f70e0)
1e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===//
2e78f53d1SNikolas Klauser //
3e78f53d1SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4e78f53d1SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information.
5e78f53d1SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6e78f53d1SNikolas Klauser //
7e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===//
8e78f53d1SNikolas Klauser 
9*ce777190SNikolas Klauser #ifndef _LIBCPP___CXX03___ALGORITHM_MAKE_HEAP_H
10*ce777190SNikolas Klauser #define _LIBCPP___CXX03___ALGORITHM_MAKE_HEAP_H
11e78f53d1SNikolas Klauser 
1273fbae83SNikolas Klauser #include <__cxx03/__algorithm/comp.h>
1373fbae83SNikolas Klauser #include <__cxx03/__algorithm/comp_ref_type.h>
1473fbae83SNikolas Klauser #include <__cxx03/__algorithm/iterator_operations.h>
1573fbae83SNikolas Klauser #include <__cxx03/__algorithm/sift_down.h>
1673fbae83SNikolas Klauser #include <__cxx03/__config>
1773fbae83SNikolas Klauser #include <__cxx03/__iterator/iterator_traits.h>
1873fbae83SNikolas Klauser #include <__cxx03/__utility/move.h>
19e78f53d1SNikolas Klauser 
20e78f53d1SNikolas Klauser #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
21e78f53d1SNikolas Klauser #  pragma GCC system_header
22e78f53d1SNikolas Klauser #endif
23e78f53d1SNikolas Klauser 
24e78f53d1SNikolas Klauser _LIBCPP_PUSH_MACROS
2573fbae83SNikolas Klauser #include <__cxx03/__undef_macros>
26e78f53d1SNikolas Klauser 
27e78f53d1SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD
28e78f53d1SNikolas Klauser 
29e78f53d1SNikolas Klauser template <class _AlgPolicy, class _Compare, class _RandomAccessIterator>
30e78f53d1SNikolas Klauser inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void
31e78f53d1SNikolas Klauser __make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare&& __comp) {
32e78f53d1SNikolas Klauser   __comp_ref_type<_Compare> __comp_ref = __comp;
33e78f53d1SNikolas Klauser 
34e78f53d1SNikolas Klauser   using difference_type = typename iterator_traits<_RandomAccessIterator>::difference_type;
35e78f53d1SNikolas Klauser   difference_type __n   = __last - __first;
36e78f53d1SNikolas Klauser   if (__n > 1) {
37e78f53d1SNikolas Klauser     // start from the first parent, there is no need to consider children
38e78f53d1SNikolas Klauser     for (difference_type __start = (__n - 2) / 2; __start >= 0; --__start) {
39e78f53d1SNikolas Klauser       std::__sift_down<_AlgPolicy>(__first, __comp_ref, __n, __first + __start);
40e78f53d1SNikolas Klauser     }
41e78f53d1SNikolas Klauser   }
42e78f53d1SNikolas Klauser }
43e78f53d1SNikolas Klauser 
44e78f53d1SNikolas Klauser template <class _RandomAccessIterator, class _Compare>
45e78f53d1SNikolas Klauser inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
46e78f53d1SNikolas Klauser make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) {
47e78f53d1SNikolas Klauser   std::__make_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp);
48e78f53d1SNikolas Klauser }
49e78f53d1SNikolas Klauser 
50e78f53d1SNikolas Klauser template <class _RandomAccessIterator>
51e78f53d1SNikolas Klauser inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
52e78f53d1SNikolas Klauser make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) {
53e78f53d1SNikolas Klauser   std::make_heap(std::move(__first), std::move(__last), __less<>());
54e78f53d1SNikolas Klauser }
55e78f53d1SNikolas Klauser 
56e78f53d1SNikolas Klauser _LIBCPP_END_NAMESPACE_STD
57e78f53d1SNikolas Klauser 
58e78f53d1SNikolas Klauser _LIBCPP_POP_MACROS
59e78f53d1SNikolas Klauser 
60*ce777190SNikolas Klauser #endif // _LIBCPP___CXX03___ALGORITHM_MAKE_HEAP_H
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