class OnlyOneLinkGraphManager :
        public artis::pdevs::GraphManager<artis::common::DoubleTime> {
public:
    enum submodels {
        GENERATOR, LINK, COUNTER
    };

    OnlyOneLinkGraphManager(artis::common::Coordinator<artis::common::DoubleTime>* coordinator,
            const artis::common::NoParameters& parameters,
            const artis::common::NoParameters& graph_parameters)
            :
            artis::pdevs::GraphManager<artis::common::DoubleTime>(
                    coordinator, parameters, graph_parameters),
            _generator("generator", artis::common::NoParameters()),
            _link("link", artis::common::NoParameters()),
            _counter("counter", artis::common::NoParameters())
    {
        add_child(GENERATOR, &_generator);
        add_child(LINK, &_link);
        add_child(COUNTER, &_counter);

        out({&_generator, Generator::outputs::OUT})
                >> in({&_link, Link::inputs::IN});
        out({&_link, Link::outputs::OUT})
                >> in({&_counter, Counter::inputs::IN});
    }

    ~OnlyOneLinkGraphManager() override = default;

private:
    artis::pdevs::Simulator<artis::common::DoubleTime, Generator> _generator;
    artis::pdevs::Simulator<artis::common::DoubleTime, Link> _link;
    artis::pdevs::Simulator<artis::common::DoubleTime, Counter> _counter;
};