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) (constexpr since C++26)

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.

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)