text: #ifndef STOCK20_H
  #define STOCK20_H
  
  #include <iostream>
  
  
  class Stock
  {
      private:
          char * company;
          int shares;
          double share_val;
          double total_val;
          void set_tot(){total_val = shares * share_val;}
      public:
          Stock();
          Stock(const char * co, long n = 0, double pr = 0.0);
          ~Stock();
  
          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;
          friend std:: ostream & operator<<(std::ostream & os, const Stock & st);
  };
  
  #endif
  