25 Algorithms library [algorithms]

25.7 Sorting and related operations [alg.sorting]

25.7.1 Sorting [alg.sort]

25.7.1.2 stable_­sort [stable.sort]

template<class RandomAccessIterator> void stable_sort(RandomAccessIterator first, RandomAccessIterator last); template<class ExecutionPolicy, class RandomAccessIterator> void stable_sort(ExecutionPolicy&& exec, RandomAccessIterator first, RandomAccessIterator last); template<class RandomAccessIterator, class Compare> void stable_sort(RandomAccessIterator first, RandomAccessIterator last, Compare comp); template<class ExecutionPolicy, class RandomAccessIterator, class Compare> void stable_sort(ExecutionPolicy&& exec, 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> I ranges::stable_sort(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> safe_iterator_t<R> ranges::stable_sort(R&& r, Comp comp = {}, Proj proj = {});
Let comp be less{} and proj be identity{} for the overloads with no parameters by those names.
Requires: For the overloads in namespace std, RandomAccessIterator shall meet the Cpp17ValueSwappable requirements ([swappable.requirements]) and the type of *first shall meet the Cpp17MoveConstructible (Table 26) and Cpp17MoveAssignable (Table 28) requirements.
Effects: Sorts the elements in the range [first, last) with respect to comp and proj.
Returns: last for the overloads in namespace ranges.
Complexity: Let N be last - first.
If enough extra memory is available, comparisons.
Otherwise, at most comparisons.
In either case, twice as many projections as the number of comparisons.
Remarks: Stable ([algorithm.stable]).