class semaphore {public:  semaphore (int nr = 1) : maxnr_(nr) {number = 0;}  ~semaphore () {;}  int acquire ();  void wait();  void p();  void release ();  void signal();  void v();/*int trywait();*/private:  leda_mutex semalock, aclock, numlock;  int number;  int maxnr_;};