NAME¶

std::flat_map::size - std::flat_map::size

Synopsis¶

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

Returns the number of elements in the container adaptor. Equivalent to return
c.keys.size().

Parameters¶

(none)

Return value¶

The number of elements in the container adaptor.

Complexity¶

Constant.

Example¶

The following code uses size to display the number of elements in a std::flat_map:

// Run this code

#include <iostream>
#include <flat_map>

int main()
{
std::flat_map<int,char> nums{{1, 'a'}, {3, 'b'}, {5, 'c'}, {7, 'd'}};

std::cout << "nums contains " << nums.size() << " elements.\n";
}

Output:¶

nums contains 4 elements.

See also¶

empty checks whether the container adaptor is empty
(public member function)
size
ssize returns the size of a container or array
(C++17) (function template)
(C++20)
max_size returns the maximum possible number of elements
(public member function)