Constrained algorithms (since C++20)

 

C++

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Feature test macros (C++20)

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Concepts library (C++20)

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Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

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Filesystem library (C++17)

Regular expressions library (C++11)

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Technical specifications

Symbols index

External libraries

 

Algorithm library

Constrained algorithms and algorithms on ranges (C++20)
Constrained algorithms, e.g. ranges::copy, ranges::sort, ...
Execution policies (C++17)
is_execution_policy (C++17)	execution::seqexecution::parexecution::par_unseqexecution::unseq (C++17)(C++17)(C++17)(C++20)	execution::sequenced_policyexecution::parallel_policyexecution::parallel_unsequenced_policyexecution::parallel_unsequenced (C++17)(C++17)(C++17)(C++20)
Non-modifying sequence operations
all_ofany_ofnone_of (C++11)(C++11)(C++11) for_each for_each_n (C++17)	countcount_if mismatch equal adjacent_find	search search_n lexicographical_compare lexicographical_compare_three_way (C++20)	findfind_iffind_if_not (C++11) find_end find_first_of
Modifying sequence operations
copycopy_if (C++11) copy_n (C++11) copy_backward move (C++11) move_backward (C++11) shift_leftshift_right (C++20)(C++20) transform	fill fill_n generate generate_n swap iter_swap swap_ranges sample (C++17)	removeremove_if replacereplace_if reverse rotate unique random_shuffle (until C++17)	remove_copyremove_copy_if replace_copyreplace_copy_if reverse_copy rotate_copy unique_copy shuffle (C++11)
Partitioning operations
is_partitioned (C++11) partition_point (C++11)	partition partition_copy (C++11)	stable_partition
Sorting operations
is_sorted (C++11) is_sorted_until (C++11)	sort stable_sort	partial_sort partial_sort_copy	nth_element
Binary search operations
lower_bound	upper_bound	binary_search	equal_range
Set operations (on sorted ranges)
merge inplace_merge	set_difference set_intersection	set_symmetric_difference set_union	includes
Heap operations
is_heap (C++11) is_heap_until (C++11)	make_heap sort_heap	push_heap pop_heap
Minimum/maximum operations
max max_element	min min_element	minmax (C++11) minmax_element (C++11)	clamp (C++17)
Permutations
is_permutation (C++11)	next_permutation	prev_permutation
Numeric operations
iota (C++11) inner_product adjacent_difference	accumulate reduce (C++17) transform_reduce (C++17)	transform_inclusive_scan (C++17) transform_exclusive_scan (C++17)	partial_sum inclusive_scan (C++17) exclusive_scan (C++17)
Operations on uninitialized storage
uninitialized_copy uninitialized_move (C++17) uninitialized_fill	uninitialized_copy_n (C++11) uninitialized_move_n (C++17) uninitialized_fill_n	uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17)	destroy (C++17) destroy_n (C++17) destroy_at (C++17) construct_at (C++20)
C library
qsort	bsearch

 

Constrained algorithms

Non-modifying sequence operations
ranges::all_ofranges::any_ofranges::none_of ranges::for_each ranges::for_each_n ranges::lexicographical_compare      ranges::adjacent_find	ranges::countranges::count_if ranges::mismatch ranges::equal ranges::containsranges::contains_subrange (C++23)(C++23)	ranges::findranges::find_ifranges::find_if_not ranges::find_lastranges::find_last_ifranges::find_last_if_not (C++23)(C++23)(C++23)	ranges::find_end ranges::find_first_of ranges::search ranges::search_n ranges::starts_with (C++23) ranges::ends_with (C++23)
Modifying sequence operations
ranges::copyranges::copy_if ranges::copy_n ranges::copy_backward ranges::move ranges::move_backward ranges::shift_leftranges::shift_right (C++23)(C++23)   ranges::transform	ranges::fill ranges::fill_n ranges::generate ranges::generate_n ranges::swap_ranges ranges::shuffle ranges::sample	ranges::removeranges::remove_if ranges::replaceranges::replace_if ranges::reverse ranges::rotate ranges::unique	ranges::remove_copyranges::remove_copy_if ranges::replace_copyranges::replace_copy_if ranges::reverse_copy ranges::rotate_copy ranges::unique_copy
Partitioning operations
ranges::is_partitioned ranges::partition_point	ranges::partition ranges::partition_copy	ranges::stable_partition
Sorting operations
ranges::is_sorted ranges::is_sorted_until	ranges::sort ranges::stable_sort	ranges::partial_sort ranges::partial_sort_copy	ranges::nth_element
Binary search operations
ranges::lower_bound	ranges::upper_bound	ranges::binary_search	ranges::equal_range
Set operations (on sorted ranges)
ranges::merge ranges::inplace_merge	ranges::set_difference ranges::set_intersection	ranges::set_symmetric_difference    ranges::set_union	ranges::includes
Heap operations
ranges::is_heap ranges::is_heap_until	ranges::make_heap ranges::sort_heap	ranges::push_heap ranges::pop_heap
Minimum/maximum operations
ranges::max ranges::max_element	ranges::min ranges::min_element	ranges::minmax ranges::minmax_element	ranges::clamp
Permutations
ranges::is_permutation	ranges::next_permutation	ranges::prev_permutation
Numeric operations
ranges::iota (C++23)
Fold operations
ranges::fold_left (C++23) ranges::fold_left_first (C++23)	ranges::fold_right (C++23) ranges::fold_right_last (C++23)	ranges::fold_left_with_iter (C++23) ranges::fold_left_first_with_iter (C++23)
Operations on uninitialized storage
ranges::construct_at ranges::destroy ranges::destroy_n ranges::destroy_at	ranges::uninitialized_copy    ranges::uninitialized_move ranges::uninitialized_fill	ranges::uninitialized_copy_n    ranges::uninitialized_move_n ranges::uninitialized_fill_n	ranges::uninitialized_default_construct ranges::uninitialized_default_construct_n    ranges::uninitialized_value_construct ranges::uninitialized_value_construct_n
Return types
ranges::in_fun_result ranges::in_in_result ranges::in_found_result	ranges::in_out_result ranges::in_in_out_result	ranges::in_out_out_result ranges::min_max_result	ranges::out_value_result (C++23) ranges::in_value_result (C++23)

 

C++20 provides constrained versions of most algorithms in the namespace std::ranges. In these algorithms, a range can be specified as either an iterator-sentinel pair or as a single range argument, and projections and pointer-to-member callables are supported. Additionally, the return types of most algorithms have been changed to return all potentially useful information computed during the execution of the algorithm.

Constrained algorithms

Defined in header <algorithm>
Defined in namespace std::ranges
Non-modifying sequence operations
ranges::all_ofranges::any_ofranges::none_of (C++20)(C++20)(C++20)	checks if a predicate is true for all, any or none of the elements in a range (niebloid)
ranges::for_each (C++20)	applies a function to a range of elements (niebloid)
ranges::for_each_n (C++20)	applies a function object to the first n elements of a sequence (niebloid)
ranges::countranges::count_if (C++20)(C++20)	returns the number of elements satisfying specific criteria (niebloid)
ranges::mismatch (C++20)	finds the first position where two ranges differ (niebloid)
ranges::equal (C++20)	determines if two sets of elements are the same (niebloid)
ranges::lexicographical_compare (C++20)	returns true if one range is lexicographically less than another (niebloid)
ranges::findranges::find_ifranges::find_if_not (C++20)(C++20)(C++20)	finds the first element satisfying specific criteria (niebloid)
ranges::find_lastranges::find_last_ifranges::find_last_if_not (C++23)(C++23)(C++23)	finds the last element satisfying specific criteria (niebloid)
ranges::find_end (C++20)	finds the last sequence of elements in a certain range (niebloid)
ranges::find_first_of (C++20)	searches for any one of a set of elements (niebloid)
ranges::adjacent_find (C++20)	finds the first two adjacent items that are equal (or satisfy a given predicate) (niebloid)
ranges::search (C++20)	searches for a range of elements (niebloid)
ranges::search_n (C++20)	searches for a number consecutive copies of an element in a range (niebloid)
ranges::containsranges::contains_subrange (C++23)(C++23)	checks if the range contains the given element or subrange (niebloid)
ranges::starts_with (C++23)	checks whether a range starts with another range (niebloid)
ranges::ends_with (C++23)	checks whether a range ends with another range (niebloid)
Modifying sequence operations
ranges::copyranges::copy_if (C++20)(C++20)	copies a range of elements to a new location (niebloid)
ranges::copy_n (C++20)	copies a number of elements to a new location (niebloid)
ranges::copy_backward (C++20)	copies a range of elements in backwards order (niebloid)
ranges::move (C++20)	moves a range of elements to a new location (niebloid)
ranges::move_backward (C++20)	moves a range of elements to a new location in backwards order (niebloid)
ranges::fill (C++20)	assigns a range of elements a certain value (niebloid)
ranges::fill_n (C++20)	assigns a value to a number of elements (niebloid)
ranges::transform (C++20)	applies a function to a range of elements (niebloid)
ranges::generate (C++20)	saves the result of a function in a range (niebloid)
ranges::generate_n (C++20)	saves the result of N applications of a function (niebloid)
ranges::removeranges::remove_if (C++20)(C++20)	removes elements satisfying specific criteria (niebloid)
ranges::remove_copyranges::remove_copy_if (C++20)(C++20)	copies a range of elements omitting those that satisfy specific criteria (niebloid)
ranges::replaceranges::replace_if (C++20)(C++20)	replaces all values satisfying specific criteria with another value (niebloid)
ranges::replace_copyranges::replace_copy_if (C++20)(C++20)	copies a range, replacing elements satisfying specific criteria with another value (niebloid)
ranges::swap_ranges (C++20)	swaps two ranges of elements (niebloid)
ranges::reverse (C++20)	reverses the order of elements in a range (niebloid)
ranges::reverse_copy (C++20)	creates a copy of a range that is reversed (niebloid)
ranges::rotate (C++20)	rotates the order of elements in a range (niebloid)
ranges::rotate_copy (C++20)	copies and rotate a range of elements (niebloid)
ranges::shuffle (C++20)	randomly re-orders elements in a range (niebloid)
ranges::shift_leftranges::shift_right (C++23)	shifts elements in a range (niebloid)
ranges::sample (C++20)	selects n random elements from a sequence (niebloid)
ranges::unique (C++20)	removes consecutive duplicate elements in a range (niebloid)
ranges::unique_copy (C++20)	creates a copy of some range of elements that contains no consecutive duplicates (niebloid)
Partitioning operations
ranges::is_partitioned (C++20)	determines if the range is partitioned by the given predicate (niebloid)
ranges::partition (C++20)	divides a range of elements into two groups (niebloid)
ranges::partition_copy (C++20)	copies a range dividing the elements into two groups (niebloid)
ranges::stable_partition (C++20)	divides elements into two groups while preserving their relative order (niebloid)
ranges::partition_point (C++20)	locates the partition point of a partitioned range (niebloid)
Sorting operations
ranges::is_sorted (C++20)	checks whether a range is sorted into ascending order (niebloid)
ranges::is_sorted_until (C++20)	finds the largest sorted subrange (niebloid)
ranges::sort (C++20)	sorts a range into ascending order (niebloid)
ranges::partial_sort (C++20)	sorts the first N elements of a range (niebloid)
ranges::partial_sort_copy (C++20)	copies and partially sorts a range of elements (niebloid)
ranges::stable_sort (C++20)	sorts a range of elements while preserving order between equal elements (niebloid)
ranges::nth_element (C++20)	partially sorts the given range making sure that it is partitioned by the given element (niebloid)
Binary search operations (on sorted ranges)
ranges::lower_bound (C++20)	returns an iterator to the first element not less than the given value (niebloid)
ranges::upper_bound (C++20)	returns an iterator to the first element greater than a certain value (niebloid)
ranges::binary_search (C++20)	determines if an element exists in a partially-ordered range (niebloid)
ranges::equal_range (C++20)	returns range of elements matching a specific key (niebloid)
Set operations (on sorted ranges)
ranges::merge (C++20)	merges two sorted ranges (niebloid)
ranges::inplace_merge (C++20)	merges two ordered ranges in-place (niebloid)
ranges::includes (C++20)	returns true if one sequence is a subsequence of another (niebloid)
ranges::set_difference (C++20)	computes the difference between two sets (niebloid)
ranges::set_intersection (C++20)	computes the intersection of two sets (niebloid)
ranges::set_symmetric_difference (C++20)	computes the symmetric difference between two sets (niebloid)
ranges::set_union (C++20)	computes the union of two sets (niebloid)
Heap operations
ranges::is_heap (C++20)	checks if the given range is a max heap (niebloid)
ranges::is_heap_until (C++20)	finds the largest subrange that is a max heap (niebloid)
ranges::make_heap (C++20)	creates a max heap out of a range of elements (niebloid)
ranges::push_heap (C++20)	adds an element to a max heap (niebloid)
ranges::pop_heap (C++20)	removes the largest element from a max heap (niebloid)
ranges::sort_heap (C++20)	turns a max heap into a range of elements sorted in ascending order (niebloid)
Minimum/maximum operations
ranges::max (C++20)	returns the greater of the given values (niebloid)
ranges::max_element (C++20)	returns the largest element in a range (niebloid)
ranges::min (C++20)	returns the smaller of the given values (niebloid)
ranges::min_element (C++20)	returns the smallest element in a range (niebloid)
ranges::minmax (C++20)	returns the smaller and larger of two elements (niebloid)
ranges::minmax_element (C++20)	returns the smallest and the largest elements in a range (niebloid)
ranges::clamp (C++20)	clamps a value between a pair of boundary values (niebloid)
Permutation operations
ranges::is_permutation (C++20)	determines if a sequence is a permutation of another sequence (niebloid)
ranges::next_permutation (C++20)	generates the next greater lexicographic permutation of a range of elements (niebloid)
ranges::prev_permutation (C++20)	generates the next smaller lexicographic permutation of a range of elements (niebloid)

Constrained numeric operations

Defined in header <numeric>
Defined in namespace std::ranges
ranges::iota (C++23)	fills a range with successive increments of the starting value (niebloid)

Constrained fold operations

Defined in header <algorithm>
Defined in namespace std::ranges
ranges::fold_left (C++23)	left-folds a range of elements (niebloid)
ranges::fold_left_first (C++23)	left-folds a range of elements using the first element as an initial value (niebloid)
ranges::fold_right (C++23)	right-folds a range of elements (niebloid)
ranges::fold_right_last (C++23)	right-folds a range of elements using the last element as an initial value (niebloid)
ranges::fold_left_with_iter (C++23)	left-folds a range of elements, and returns a pair (iterator, value) (niebloid)
ranges::fold_left_first_with_iter (C++23)	left-folds a range of elements using the first element as an initial value, and returns a pair (iterator, optional) (niebloid)

Constrained uninitialized memory algorithms

Defined in header <memory>
Defined in namespace std::ranges
ranges::uninitialized_copy (C++20)	copies a range of objects to an uninitialized area of memory (niebloid)
ranges::uninitialized_copy_n (C++20)	copies a number of objects to an uninitialized area of memory (niebloid)
ranges::uninitialized_fill (C++20)	copies an object to an uninitialized area of memory, defined by a range (niebloid)
ranges::uninitialized_fill_n (C++20)	copies an object to an uninitialized area of memory, defined by a start and a count (niebloid)
ranges::uninitialized_move (C++20)	moves a range of objects to an uninitialized area of memory (niebloid)
ranges::uninitialized_move_n (C++20)	moves a number of objects to an uninitialized area of memory (niebloid)
ranges::uninitialized_default_construct (C++20)	constructs objects by default-initialization in an uninitialized area of memory, defined by a range (niebloid)
ranges::uninitialized_default_construct_n (C++20)	constructs objects by default-initialization in an uninitialized area of memory, defined by a start and count (niebloid)
ranges::uninitialized_value_construct (C++20)	constructs objects by value-initialization in an uninitialized area of memory, defined by a range (niebloid)
ranges::uninitialized_value_construct_n (C++20)	constructs objects by value-initialization in an uninitialized area of memory, defined by a start and a count (niebloid)
ranges::destroy (C++20)	destroys a range of objects (niebloid)
ranges::destroy_n (C++20)	destroys a number of objects in a range (niebloid)
ranges::destroy_at (C++20)	destroys an object at a given address (niebloid)
ranges::construct_at (C++20)	creates an object at a given address (niebloid)

Return types

Defined in header <algorithm>
Defined in namespace std::ranges
ranges::in_fun_result (C++20)	provides a way to store an iterator and a function object as a single unit (class template)
ranges::in_in_result (C++20)	provides a way to store two iterators as a single unit (class template)
ranges::in_out_result (C++20)	provides a way to store two iterators as a single unit (class template)
ranges::in_in_out_result (C++20)	provides a way to store three iterators as a single unit (class template)
ranges::in_out_out_result (C++20)	provides a way to store three iterators as a single unit (class template)
ranges::min_max_result (C++20)	provides a way to store two objects or references of the same type as a single unit (class template)
ranges::in_found_result (C++20)	provides a way to store an iterator and a boolean flag as a single unit (class template)
ranges::in_value_result (C++23)	provides a way to store an iterator and a value as a single unit (class template)
ranges::out_value_result (C++23)	provides a way to store an iterator and a value as a single unit (class template)

Notes

Feature-test macro	Value	Std	Comment
__cpp_lib_find_last	202207L	(C++23)	std::ranges::find_last
__cpp_lib_ranges	201911L	(C++20)	Ranges library and constrained algorithms
__cpp_lib_ranges_contains	202207L	(C++23)	std::ranges::contains
__cpp_lib_ranges_fold	202207L	(C++23)	std::ranges fold algorithms
__cpp_lib_ranges_iota	202202L	(C++23)	std::ranges::iota
__cpp_lib_ranges_starts_ends_with	202106L	(C++23)	std::ranges::starts_with, std::ranges::ends_with
__cpp_lib_shift	201806L	(C++20)	std::shift_left and std::shift_right
	202202L	(C++23)	std::ranges::shift_left and std::ranges::shift_right