_Task Student {
	void main();
  public:
	Student( Printer & prt, NameServer & nameServer, WATCardOffice & cardOffice, Groupoff & groupoff,
			 unsigned int id, unsigned int maxPurchases );
};

class WATCard {
	WATCard( const WATCard & ) = delete;	// prevent copying
	WATCard( const WATCard && ) = delete;
	WATCard & operator=( const WATCard & ) = delete;
	WATCard & operator=( const WATCard && ) = delete;
  public:
	typedef Future_ISM<WATCard *> FWATCard;	// future watcard pointer
	WATCard();
	void deposit( unsigned int amount );
	void withdraw( unsigned int amount );
	unsigned int getBalance();
};

_Task WATCardOffice {
	struct Job {							// marshalled arguments and return future
		Args args;							// call arguments (YOU DEFINE "Args")
		WATCard::FWATCard result;			// return future
		Job( Args args ) : args( args ) {}
	};
	_Task Courier { ... };					// communicates with bank

	void main();
  public:
	_Exception Lost {};						// lost WATCard
	WATCardOffice( Printer & prt, Bank & bank, unsigned int numCouriers );
	WATCard::FWATCard create( unsigned int sid, unsigned int amount ) __attribute__(( warn_unused_result ));
	WATCard::FWATCard transfer( unsigned int sid, unsigned int amount, WATCard * card ) __attribute__(( warn_unused_result ));
	Job * requestWork() __attribute__(( warn_unused_result ));
};

_Monitor Bank {
  public:
	Bank( unsigned int numStudents );
	void deposit( unsigned int id, unsigned int amount );
	void withdraw( unsigned int id, unsigned int amount );
};

_Task Parent {
	void main();
  public:
	Parent( Printer & prt, Bank & bank, unsigned int numStudents, unsigned int parentalDelay );
};

_Task Groupoff {
	void main();
  public:
	Groupoff( Printer & prt, unsigned int numStudents, unsigned int sodaCost, unsigned int groupoffDelay );
	WATCard::FWATCard giftCard( unsigned int id );
};

_Task VendingMachine {
	void main();
  public:
	_Exception Funds {};					// insufficient funds
	_Exception Stock {};					// flavour out of stock
	_Exception Free {};						// free, advertisement
	VendingMachine( Printer & prt, NameServer & nameServer, unsigned int id, unsigned int sodaCost );
	void buy( BottlingPlant::Flavours flavour, WATCard & card );
	unsigned int * inventory() __attribute__(( warn_unused_result ));
	void restocked();
	_Nomutex unsigned int cost() const;
	_Nomutex unsigned int getId() const;
};

_Task NameServer {
	void main();
  public:
	NameServer( Printer & prt, unsigned int numVendingMachines, unsigned int numStudents );
	void VMregister( VendingMachine * vendingmachine );
	VendingMachine * getMachine( unsigned int id ) __attribute__(( warn_unused_result ));
	VendingMachine ** getMachineList() __attribute__(( warn_unused_result ));
};

_Task BottlingPlant {
	void main();
  public:
	enum Flavours { ..., NUM_OF_FLAVOURS };	// flavours of soda (YOU DEFINE)
	_Exception Shutdown {};					// shutdown plant
	BottlingPlant( Printer & prt, NameServer & nameServer, unsigned int numVendingMachines,
				 unsigned int maxShippedPerFlavour, unsigned int maxStockPerFlavour,
				 unsigned int timeBetweenShipments );
	void getShipment( unsigned int cargo[] );
};

_Task Truck {
	void main();
  public:
	Truck( Printer & prt, NameServer & nameServer, BottlingPlant & plant,
		   unsigned int numVendingMachines, unsigned int maxStockPerFlavour );
};

_Monitor / _Cormonitor Printer {
  public:
	enum Kind { Parent, Groupoff, WATCardOffice, NameServer, Truck, BottlingPlant, Student, Vending, Courier };
	Printer( unsigned int numStudents, unsigned int numVendingMachines, unsigned int numCouriers );
	void print( Kind kind, char state );
	void print( Kind kind, char state, unsigned int value1 );
	void print( Kind kind, char state, unsigned int value1, unsigned int value2 );
	void print( Kind kind, unsigned int lid, char state );
	void print( Kind kind, unsigned int lid, char state, unsigned int value1 );
	void print( Kind kind, unsigned int lid, char state, unsigned int value1, unsigned int value2 );
};