std::unordered_set<Key,Hash,KeyEqual,Allocator>::size
| size_type size() const noexcept; | (since C++11) | 
Returns the number of elements in the container, i.e. std::distance(begin(), end()).
Parameters
(none).
Return value
The number of elements in the container.
Complexity
Constant.
Example
The following code uses size to display the number of elements in a std::unordered_set<int>:
#include <unordered_set>
#include <iostream>
 
int main()
{ 
    std::unordered_set<int> nums {1, 3, 5, 7};
 
    std::cout << "nums contains " << nums.size() << " elements.\n";
}Output:
nums contains 4 elements.
See also
| checks whether the container is empty (public member function) | |
| returns the maximum possible number of elements (public member function) | 
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