How to program set Cardinality in C plus plus?

Answer 1

The cardinality of a set is simply the number of elements in the set. If the set is represented by an STL sequence container (such as std::array, std::vector, std::list or std::set), then the container's size() member function will return the cardinality.

For example:

std::vector<int> set {2,3,5,7,11,13};

size_t cardinality = set.size();

assert (cardinality == 6);