// stock30.h #ifndef STOCK30_H_ #define STOCK30_H_ class Stock { private: std::string company long shares; double share_val; double total_val; void set_tot() ( total_val - shares * share_val; ) public; Stock(); // default constructor Stock(const std::string & co, long n, double pr); -Stock() {} // do-nothing destructor void buy(long num, double price); void sell(long num, double price); void update(double price); void show() const; const Stock & topval(const Stock & s) const; int numshares() const ( return shares; ) double shareval() const ( return share_val; ) double totalval() const ( return total_val; ) comst string & co_name() const ( return company; ) };