std::experimental::ranges::find_first_of

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Experimental

Technical Specification

Filesystem library (filesystem TS)

Library fundamentals (library fundamentals TS)

Library fundamentals 2 (library fundamentals TS v2)

Library fundamentals 3 (library fundamentals TS v3)

Extensions for parallelism (parallelism TS)

Extensions for parallelism 2 (parallelism TS v2)

Extensions for concurrency (concurrency TS)

Extensions for concurrency 2 (concurrency TS v2)

Concepts (concepts TS)

Ranges (ranges TS)

Reflection (reflection TS)

Mathematical special functions (special functions TR)

Experimental Non-TS

Pattern Matching

Linear Algebra

std::execution

Contracts

2D Graphics

 

Ranges

Concepts

General utilities

Iterators

Ranges

Algorithms

 

Algorithms library

Non-modifying sequence operations
all_ofany_ofnone_of countcount_if	findfind_iffind_if_not find_end find_first_of	adjacent_find search search_n mismatch	equal for_each lexicographical_compare
Modifying sequence operations
copycopy_if copy_n copy_backward move move_backward	fill fill_n generate generate_n swap_ranges shuffle transform	removeremove_if replacereplace_if reverse rotate unique	remove_copyremove_copy_if 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 partial_sort_copy	nth_element
Binary search operations
lower_bound	upper_bound	binary_search	equal_range
Set operations (on sorted ranges)
merge inplace_merge	includes	set_difference set_intersection	set_symmetric_difference set_union
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
Permutations
is_permutation	next_permutation	prev_permutation

 

Defined in header <experimental/ranges/algorithm>
template< InputIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2,           class Proj1 = ranges::identity, class Proj2 = ranges::identity,           IndirectRelation<projected<I1, Proj1>,                            projected<I2, Proj2>> Pred = ranges::equal_to<> > I1 find_first_of( I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = Pred{},                   Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{} );	(1)	(ranges TS)
template< InputRange R1, ForwardRange R2,           class Proj1 = ranges::identity, class Proj2 = ranges::identity,           IndirectRelation<projected<ranges::iterator_t<R1>, Proj1>,                            projected<ranges::iterator_t<R2>, Proj2>> Pred = ranges::equal_to<> > ranges::safe_iterator_t<R1> find_first_of( R1&& r1, R2&& r2, Pred pred = Pred{},                                            Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{} );	(2)	(ranges TS)

1) Searches the range [first1, last1) for any of the elements in the range [first2, last2), after projecting the ranges with proj1 and proj2 respectively. The projected elements are compared using pred.

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

Parameters

first1, last1	-	the range of elements to examine
r1	-	the range of elements to examine
first2, last2	-	the range of elements to search for
r2	-	the range of elements to search for
pred	-	predicate to use to compare the projected elements with
proj1	-	projection to apply to the elements in the first range
proj2	-	projection to apply to the elements in the second range

Return value

Iterator to the first element in the range [first1, last1) that is equal to an element from the range [first2, last2) after projection. If no such element is found, an iterator comparing equal to last1 is returned.

Complexity

At most (S * N) applications of the predicate and each projection, where S = distance(last2 - first2) and N = last1 - first1.

Possible implementation

template<InputIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2, class Proj1 = ranges::identity, class Proj2 = ranges::identity, IndirectRelation<projected<I1, Proj1>, projected<I2, Proj2>> Pred = ranges::equal_to<>> I1 find_first_of(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = Pred{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{}) { for (; first1 != last1; ++first1) for (ForwardIt it = first2; it != last2; ++it) if (ranges::invoke(pred, ranges::invoke(proj1, *first1), ranges::invoke(proj2, *it))) return first1; return first1; }

See also

find_first_of	searches for any one of a set of elements (function template)
findfind_iffind_if_not	finds the first element satisfying specific criteria (function template)