void check_link(Block &);
Block *get_link(unsigned) const;
bool reserve(const Train *);
const Train *get_train() const { return train; }
void print_debug();
private:
void check_link(Block &);
Block *get_link(unsigned) const;
bool reserve(const Train *);
const Train *get_train() const { return train; }
void print_debug();
private: