std::ranges::includes

 

C++

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Named requirements

Feature test macros(C++20)

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Concepts library(C++20)

Diagnostics library

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Metaprogramming library(C++11)

General utilities library

Containers library

Iterators library

Ranges library(C++20)

Algorithms library

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Date and time library

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Filesystem library(C++17)

Concurrency support library(C++11)

Execution control library(C++26)

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 Batch operations for_each for_each_n (C++17) Search operations all_ofany_ofnone_of (C++11)                (C++11)(C++11) countcount_if mismatch equal findfind_iffind_if_not (C++11) find_end find_first_of adjacent_find search search_n Modifying sequence operations Copy operations copycopy_if (C++11) copy_backward copy_n (C++11) move (C++11) move_backward (C++11) Swap operations swap iter_swap swap_ranges Transformation operations replacereplace_if transform replace_copyreplace_copy_if Generation operations fill fill_n generate generate_n Removing operations removeremove_if unique remove_copyremove_copy_if unique_copy Order-changing operations reverse reverse_copy rotate rotate_copy random_shuffleshuffle (until C++17)(C++11) shift_leftshift_right (C++20)(C++20) Sampling operations sample (C++17)	Sorting and related operations Partitioning operations partition partition_copy (C++11)   stable_partition is_partitioned (C++11) partition_point (C++11) Sorting operations sort stable_sort partial_sort partial_sort_copy is_sorted (C++11) is_sorted_until (C++11) nth_element Binary search operations (on partitioned ranges) lower_bound upper_bound equal_range binary_search Set operations (on sorted ranges) includes set_union set_intersection set_difference set_symmetric_difference Merge operations (on sorted ranges) merge inplace_merge Heap operations push_heap pop_heap make_heap sort_heap is_heap (C++11) is_heap_until (C++11) Minimum/maximum operations max min minmax (C++11) clamp (C++17) max_element min_element minmax_element (C++11) Lexicographical comparison operations lexicographical_compare lexicographical_compare_three_way (C++20) Permutation operations next_permutation prev_permutation is_permutation (C++11) C library qsort bsearch
Numeric operations
iota (C++11) inner_product adjacent_difference    accumulate reduce (C++17) transform_reduce (C++17)	partial_sum inclusive_scan (C++17)    exclusive_scan (C++17) transform_inclusive_scan (C++17) transform_exclusive_scan (C++17)
Operations on uninitialized memory
uninitialized_copy uninitialized_move (C++17)    uninitialized_fill uninitialized_copy_n (C++11) uninitialized_move_n (C++17) uninitialized_fill_n	destroy (C++17) destroy_n (C++17) destroy_at (C++17) construct_at (C++20)       uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17)

 

Constrained algorithms

All names in this menu belong to namespace std::ranges

Non-modifying sequence operations

all_ofany_ofnone_of for_each for_each_n    countcount_if adjacent_find mismatch equal lexicographical_compare    containscontains_subrange (C++23)(C++23) findfind_iffind_if_not find_lastfind_last_iffind_last_if_not (C++23)(C++23)(C++23)   find_end find_first_of search search_n starts_with (C++23) ends_with (C++23)

Modifying sequence operations

copycopy_if copy_n copy_backward    move move_backward shift_leftshift_right (C++23)(C++23)   fill fill_n generate generate_n    transform swap_ranges    shuffle sample removeremove_if replacereplace_if reverse rotate remove_copyremove_copy_if    unique replace_copyreplace_copy_if reverse_copy rotate_copy unique_copy

Partitioning operations

is_partitioned    partition_point    partition    partition_copy    stable_partition

Sorting operations

is_sorted is_sorted_until     sort stable_sort         partial_sort       nth_element partial_sort_copy

Binary search operations (on sorted ranges)

lower_bound         upper_bound         binary_search      equal_range

Set operations (on sorted ranges)

merge inplace_merge       set_difference set_intersection    set_union          includes set_symmetric_difference

Heap operations

is_heap is_heap_until       make_heap           sort_heap push_heap pop_heap

Minimum/maximum operations

max max_element         min min_element         minmax minmax_element     clamp

Permutation operations

is_permutation      next_permutation    prev_permutation

Fold operations

fold_left (C++23) fold_left_first (C++23)   fold_right (C++23) fold_right_last (C++23)   fold_left_with_iter (C++23) fold_left_first_with_iter (C++23)

Numeric operations iota (C++23)             Random number generation generate_random (C++26)

Operations on uninitialized storage

construct_at    destroy destroy_n destroy_at uninitialized_copy    uninitialized_move uninitialized_fill uninitialized_copy_n    uninitialized_move_n uninitialized_fill_n uninitialized_default_construct uninitialized_default_construct_n uninitialized_value_construct uninitialized_value_construct_n

Return types

in_fun_result in_in_result in_found_result    in_out_result in_in_out_result    in_out_out_result    min_max_result out_value_result (C++23) in_value_result (C++23)

 

Defined in header <algorithm>
Call signature
template<std::input_iterator I1, std::sentinel_for<I1> S1,           std::input_iterator I2, std::sentinel_for<I2> S2,           class Proj1 =std::identity, class Proj2 =std::identity,           std::indirect_strict_weak_order<               std::projected<I1, Proj1>,               std::projected<I2, Proj2>> Comp =ranges::less> constexprbool     includes( I1 first1, S1 last1, I2 first2, S2 last2,               Comp comp ={}, Proj1 proj1 ={}, Proj2 proj2 ={})	(1)	(since C++20)
template<ranges::input_range R1, ranges::input_range R2,           class Proj1 =std::identity, class Proj2 =std::identity,           std::indirect_strict_weak_order<               std::projected<ranges::iterator_t<R1>, Proj1>,               std::projected<ranges::iterator_t<R2>, Proj2>> Comp =ranges::less> constexprbool     includes( R1&& r1, R2&& r2, Comp comp ={}, Proj1 proj1 ={}, Proj2 proj2 ={})	(2)	(since C++20)

1) Returns true if the projections of the sorted range [first2, last2) is a subsequence of the projections of the sorted range [first1, last1).

2) Same as (1), but uses r1 and r2 as the source ranges, as if by using ranges::begin(r1) and ranges::begin(r2) as first1 and first2 respectively, and ranges::end(r1) and ranges::end(r2) as last1 and last2 respectively.

Both ranges must be sorted with the given comparison function comp. A subsequence need not be contiguous.

The function-like entities described on this page are algorithm function objects (informally known as niebloids), that is:

• Explicit template argument lists cannot be specified when calling any of them.
• None of them are visible to argument-dependent lookup.
• When any of them are found by normal unqualified lookup as the name to the left of the function-call operator, argument-dependent lookup is inhibited.

Parameters

first1, last1	-	the iterator-sentinel pair defining the sorted range of elements to examine
r1	-	the sorted range of elements to examine
first2, last2	-	the iterator-sentinel pair defining the sorted range of elements to search for
r2	-	the sorted range of elements to search for
comp	-	comparison function to apply to the projected elements
proj1	-	projection to apply to the elements in the first range
proj2	-	projection to apply to the elements in the second range

Return value

true if [first2, last2) is a subsequence of [first1, last1); otherwise false.

Complexity

At most \(\scriptsize 2 \cdot (N_1+N_2-1)\)2·(N₁+N₂-1) comparisons, where \(\scriptsize N_1\)N₁ is ranges::distance(r1) and \(\scriptsize N_2\)N₂ is ranges::distance(r2).

Possible implementation

struct includes_fn {template<std::input_iterator I1, std::sentinel_for<I1> S1, std::input_iterator I2, std::sentinel_for<I2> S2, class Proj1 =std::identity, class Proj2 =std::identity, std::indirect_strict_weak_order< std::projected<I1, Proj1>, std::projected<I2, Proj2>> Comp =ranges::less>constexprbool operator()(I1 first1, S1 last1, I2 first2, S2 last2, Comp comp ={}, Proj1 proj1 ={}, Proj2 proj2 ={})const{for(; first2 != last2;++first1){if(first1 == last1 || comp(*first2, *first1))returnfalse;if(!comp(*first1, *first2))++first2;}returntrue;}   template<ranges::input_range R1, ranges::input_range R2, class Proj1 =std::identity, class Proj2 =std::identity, std::indirect_strict_weak_order< std::projected<ranges::iterator_t<R1>, Proj1>, std::projected<ranges::iterator_t<R2>, Proj2>> Comp =ranges::less>constexprbool operator()(R1&& r1, R2&& r2, Comp comp ={}, Proj1 proj1 ={}, Proj2 proj2 ={})const{return(*this)(ranges::begin(r1), ranges::end(r1), ranges::begin(r2), ranges::end(r2), std::ref(comp), std::ref(proj1), std::ref(proj2));}};   inlineconstexprauto includes = includes_fn {};

Example

Run this code

#include <algorithm>#include <cctype>#include <initializer_list>#include <iomanip>#include <iostream>#include <locale>#include <string>   template<class T>std::ostream& operator<<(std::ostream& os, std::initializer_list<T>const& list){for(os <<"{ ";autoconst& elem : list) os << elem <<' ';return os <<"} ";}   struct true_false :std::numpunct<char>{std::string do_truename()const{return"? Yes\n";}std::string do_falsename()const{return"? No\n";}};   int main(){std::cout.imbue(std::locale(std::cout.getloc(), new true_false));   auto ignore_case =[](char a, char b){returnstd::tolower(a)<std::tolower(b);};   constauto a ={'a', 'b', 'c'}, b ={'a', 'c'}, c ={'a', 'a', 'b'}, d ={'g'}, e ={'a', 'c', 'g'}, f ={'A', 'B', 'C'}, z ={'a', 'b', 'c', 'f', 'h', 'x'};   std::cout<< z <<"includes\n"<<std::boolalpha<< a << std::ranges::includes(z.begin(), z.end(), a.begin(), a.end())<< b << std::ranges::includes(z, b)<< c << std::ranges::includes(z, c)<< d << std::ranges::includes(z, d)<< e << std::ranges::includes(z, e)<< f << std::ranges::includes(z, f, ignore_case);}

Output:

{ a b c f h x } includes { a b c } ? Yes { a c } ? Yes { a a b } ? No { g } ? No { a c g } ? No { A B C } ? Yes

See also

ranges::set_difference (C++20)	computes the difference between two sets (algorithm function object)
ranges::search (C++20)	searches for the first occurrence of a range of elements (algorithm function object)
ranges::containsranges::contains_subrange (C++23)(C++23)	checks if the range contains the given element or subrange (algorithm function object)
includes	returns true if one sequence is a subsequence of another (function template)