Bjarne
Stroustrup
AEIOU
aeiou
AEIOUxaeiou
___
#include "a9.h"
#include <cassert>
#include <iostream>

using namespace std;

template<typename T>
class Set {
    public:
        Set();
        Set(const List<T>&);
        void insert(const T&);
        bool member(const T&) const;
        void remove(const T&);
        int size() const { return itsValueCount; }
        List<T> values() const;

    template<typename T1> friend Set<T1> operator+(const Set<T1>&, const Set<T1>&);
    template<typename T1> friend Set<T1> operator*(const Set<T1>&, const Set<T1>&);
    template<typename T1> friend Set<T1> operator-(const Set<T1>&, const Set<T1>&);
    private:
    };