std::flat_set<Key,Compare,KeyContainer>::size

 

C++

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Feature test macros (C++20)

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Technical specifications

Symbols index

External libraries

 

Containers library

node-handle (C++17)

Sequence

array (C++11)

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list

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unordered_set (C++11)

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stack

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flat_set (C++23)

flat_multiset (C++23)

flat_map (C++23)

flat_multimap (C++23)

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span (C++20)

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std::flat_set

Member types

Member functions

flat_set::flat_set flat_set::operator= Iterators flat_set::beginflat_set::cbegin flat_set::endflat_set::cend flat_set::rbeginflat_set::crbegin flat_set::rendflat_set::crend Capacity flat_set::size flat_set::max_size flat_set::empty Observers flat_set::key_comp flat_set::value_comp      Modifiers flat_set::clear flat_set::insert flat_set::insert_range flat_set::emplace flat_set::emplace_hint flat_set::erase flat_set::swap flat_set::extract flat_set::replace Lookup flat_set::count flat_set::find flat_set::contains flat_set::equal_range flat_set::lower_bound flat_set::upper_bound Non-member functions operator==operator<=> swap(std::flat_set) erase_if(std::flat_set)

Helper classes

uses_allocator<std::flat_set>

Tags

sorted_unique      sorted_unique_t

Deduction guides

 

size_type size() const noexcept;		(since C++23)

Returns the number of elements in the container adaptor. Equivalent to: return c.size().

Parameters

(none)

Return value

The number of elements in the container adaptor.

Complexity

Constant.

Example

Run this code

#include <cassert>
#include <flat_set>
 
int main()
{
    std::flat_set<int> nums{4, 2, 4, 2};
    assert(nums.size() == 2);
}

See also

empty	checks whether the container adaptor is empty (public member function)
sizessize (C++17)(C++20)	returns the size of a container or array (function template)
max_size	returns the maximum possible number of elements (public member function)

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