NAME¶

std::flat_map::max_size - std::flat_map::max_size

Synopsis¶

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

Returns the maximum number of elements the container is able to hold due to system
or library implementation limitations. Equivalent to
std::min<size_type>(c.keys.max_size(), c.values.max_size()).

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 <flat_map>
#include <locale>

int main()
{
std::flat_map<char, char> q;
std::cout.imbue(std::locale("en_US.UTF-8"));
std::cout << "Maximum size of a std::flat_map is " << q.max_size() << '\n';
}

Possible output:¶

Maximum size of a std::flat_map is 768,614,336,404,564,650

See also¶

size returns the number of elements
(public member function)