auction.cpp

class Auctioneer {
  typedef float Currency;
  Currency price;
  std::vector<Currency> bids;
  
  public:
  /** Accept a buyer's bid.
   * id int Buyer's id.
   * price Currency Buyer's bid price.
   */
  void bid(int id, Currency price);
  Currency currentPrice();
  void update();
};

class Buyer {
  int id;
  // Other fields here.
  public:
  void bid(Auctioneer &a);
}