class StreamExercises {

    public static int countBandMembersExternal(List<Artist> artists) {
        // BEGIN COUNT_MEMBERS_EXTERNAL
    int totalMembers = 0;
    for (Artist artist : artists) {
        Stream<Artist> members = artist.getMembers();
        totalMembers += members.count();
    }
        // END COUNT_MEMBERS_EXTERNAL

        return totalMembers;
    }

}