anchor.diff:              {NewPortfolio, NewTransactions} = transaction(
                   choice([buy, sell]), Symbol, Price, 1, Portfolio, Transactions
               ),
  +            io:format("~p~n", [Prices]),
               io:format("~p~n", [dict:to_list(NewPortfolio)]),
               io:format("~p~n", [NewTransactions]),
               io:format("~n"),
  
positive.code: 
  %% Pick and return a random element from a given list
  choice(List) ->
      Maximum = length(List),
      Element = random:uniform(Maximum),
      lists:nth(Element, List).
  
negative.code: -define(MAX_LISTINGS, 5).
  -define(MAX_BROKERS, 3).
  -define(TICKER_INTERVAL, 1000).
  -define(MAX_RANDOM_SLEEP, 100).
  
  
  %%%----------------------------------------------------------------------------
  