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

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

#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';
}

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

See also