std::flat_multiset<Key,Compare,KeyContainer>::clear

 

C++

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Symbols index

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Containers library

Sequence

array (C++11)

vector

vector<bool>

inplace_vector (C++26)

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forward_list (C++11)

list

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multiset

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unordered_set (C++11)

unordered_multiset (C++11)

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unordered_multimap (C++11)

Adaptors

stack

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flat_set (C++23)

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flat_multimap (C++23)

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span (C++20)

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std::flat_multiset

Member types

Member functions

flat_multiset::flat_multiset   flat_multiset::operator= Iterators flat_multiset::beginflat_multiset::cbegin flat_multiset::endflat_multiset::cend flat_multiset::rbeginflat_multiset::crbegin flat_multiset::rendflat_multiset::crend Capacity flat_multiset::size flat_multiset::max_size flat_multiset::empty Observers flat_multiset::key_comp flat_multiset::value_comp Modifiers flat_multiset::clear flat_multiset::insert flat_multiset::insert_range flat_multiset::emplace flat_multiset::emplace_hint flat_multiset::erase flat_multiset::swap flat_multiset::extract flat_multiset::replace Lookup flat_multiset::count flat_multiset::find flat_multiset::contains flat_multiset::equal_range flat_multiset::lower_bound flat_multiset::upper_bound

Non-member functions

swap(std::flat_multiset) erase_if(std::flat_multiset)    operator==operator<=>

Helper classes

uses_allocator<std::flat_multiset>

Tags

sorted_equivalent         sorted_equivalent_t

Deduction guides

 

void clear() noexcept;		(since C++23)

Erases all elements from the container adaptor. After this call, size() returns zero.

Invalidates any references, pointers, and iterators referring to contained elements.

Parameters

(none)

Return value

(none)

Complexity

Linear in the size of the container adaptor, i.e., the number of elements.

Example

Run this code

#include <iostream>
#include <string_view>
#include <flat_set>
 
void print_info(std::string_view rem, const std::flat_multiset<int>& v)
{
    std::cout << rem << "{ ";
    for (const auto& value : v)
        std::cout << value << ' ';
    std::cout << "}\n";
    std::cout << "Size=" << v.size() << '\n';
}
 
int main()
{
    std::flat_multiset<int> container{1, 2, 3};
    print_info("Before clear: ", container);
    container.clear();
    print_info("After clear: ", container);
}

Output:

Before clear: { 1 2 3 }
Size=3
After clear: { }
Size=0

See also

erase

erases elements (public member function)