25 Algorithms library [algorithms]

25.8 Sorting and related operations [alg.sorting]

25.8.8 Heap operations [alg.heap.operations]

25.8.8.4 make_­heap [make.heap]

template<class RandomAccessIterator> constexpr void make_heap(RandomAccessIterator first, RandomAccessIterator last); template<class RandomAccessIterator, class Compare> constexpr void make_heap(RandomAccessIterator first, RandomAccessIterator last, Compare comp); template<random_­access_­iterator I, sentinel_­for<I> S, class Comp = ranges::less, class Proj = identity> requires sortable<I, Comp, Proj> constexpr I ranges::make_heap(I first, S last, Comp comp = {}, Proj proj = {}); template<random_­access_­range R, class Comp = ranges::less, class Proj = identity> requires sortable<iterator_t<R>, Comp, Proj> constexpr borrowed_iterator_t<R> ranges::make_heap(R&& r, Comp comp = {}, Proj proj = {});
Let comp be less{} and proj be identity{} for the overloads with no parameters by those names.
Preconditions: For the overloads in namespace std, the type of *first meets the Cpp17MoveConstructible (Table 28) and Cpp17MoveAssignable (Table 30) requirements.
Effects: Constructs a heap with respect to comp and proj out of the range [first, last).
Returns: last for the overloads in namespace ranges.
Complexity: At most comparisons and twice as many projections.