std::flat_map<Key,T,Compare,KeyContainer,MappedContainer>::max_size

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()).

# Declarations

size_type max_size() const noexcept;

(since C++23)

# Return value

Maximum number of elements.

# 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

#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';
}

# See also

size