std::map<Key,T,Compare,Allocator>::size

Returns the number of elements in the container, i.e. std::distance(begin(), end()).

# Declarations

size_type size() const;

(noexcept since C++11)

# Return value

The number of elements in the container.

# Example

#include <cassert>
#include <map>
 
int main()
{
    std::map<int, char> nums{{1, 'a'}, {1, 'b'}, {2, 'c'}, {2, 'd'}};
    assert(nums.size() == 2); 
}

# See also