std::multimap<Key,T,Compare,Allocator>::max_size

 

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std::multimap

Member functions

multimap::multimap multimap::~multimap        multimap::operator= multimap::get_allocator

Iterators multimap::beginmultimap::cbegin (C++11) multimap::endmultimap::cend (C++11) multimap::rbeginmultimap::crbegin (C++11)    multimap::rendmultimap::crend (C++11) Capacity multimap::size multimap::max_size multimap::empty Observers multimap::key_comp multimap::value_comp Modifiers multimap::clear multimap::insert multimap::erase multimap::swap multimap::merge (C++17) multimap::insert_range (C++23) multimap::emplace (C++11) multimap::emplace_hint (C++11) multimap::extract (C++17) Lookup multimap::count multimap::find multimap::contains (C++20) multimap::equal_range multimap::lower_bound multimap::upper_bound

Non-member functions

operator==operator<=> (C++20) std::swap(std::multimap) erase_if(std::multimap) (C++20)   operator!=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)

Deduction guides(C++17)

 

size_type max_size() const;		(noexcept since C++11)

Returns the maximum number of elements the container is able to hold due to system or library implementation limitations, i.e. std::distance(begin(), end()) for the largest container.

Parameters

(none)

Return value

Maximum number of elements.

Complexity

Constant.

Notes

This value typically reflects the theoretical limit on the size of the container, at most std::numeric_limits<difference_type>::max(). At runtime, the size of the container may be limited to a value smaller than max_size() by the amount of RAM available.

Example

Run this code

#include <iostream>
#include <locale>
#include <map>
 
int main()
{
    std::multimap<char, char> p;
    std::multimap<long, char> q;
 
    std::cout.imbue(std::locale("en_US.UTF-8"));
    std::cout << std::uppercase
              << "p.max_size() = " << std::dec << p.max_size() << " = 0x"
              << std::hex << p.max_size() << '\n'
              << "q.max_size() = " << std::dec << q.max_size() << " = 0x"
              << std::hex << q.max_size() << '\n';
}

Possible output:

p.max_size() = 461,168,601,842,738,790 = 0x666,666,666,666,666
q.max_size() = 384,307,168,202,282,325 = 0x555,555,555,555,555

See also

size	returns the number of elements (public member function)