HW 12- THE Stock Broker STARTER CODE

Stock Broker
In this assignment, we simulate how stock trading works and for simplicity, we consider stocks of the
same company. A stock broker uses the priority queue to organize a bid queue and an ask queue. A bid
queue is used to organize all the buying orders of a stock, and an ask queue is used to organize all the
selling orders of this stock. Each bid or ask request has a suggested price and the number of shares. A
trade will occur if the highest bid price exceeds or meets the lowest ask price. When this happens, the
broker will step in and buy the stock from the one offers the lowest ask price, and sell the stock to the
one who offers the highest bid price and make profit when these two prices are different. If the highest
bid and the lowest ask have different number of shares, then the broker splits the larger request and
continues the trading.
The Request ADT
We store each bid or ask in an object of Request type. The Request class has the following ADT.
__init__(self, price, share) - Receives the price and the number of shares for a bid or ask
request.
__eq__(self, other) - Receives a Request and returns True if both requests have the same price
and shares.
The Broker ADT
We use Broker with the following ADT to simulate the stock broker.
__init__(self, bids, asks) - Receives a list of bid requests and a list of ask requests and store
them internally.
trade(self) - Returns a tuple containing the bid request with the highest price and the ask request
with the lowest price if the ask price is not greater than the bid price, and None otherwise.
tradeall(self) - Trades all stocks as long as the ask price is not greater than the bid price and
returns a list of trades (tuples of bid and ask requests).
getprofit(self) - Returns the obtained profit at this moment.
What to do
Implement __init__(self, bids, asks) , trade(self) , tradeall(self) , and getprofit(self) methods
of Broker class in stockbroker.py file. Let asks and bids be of and size, respectively. Then, the
time complexity of your __init__ , trade , tradeall , and getprofit methods should be ,
, , and , respectively. submit your
priorityqueue.py and stockbroker.py files to Mimir.
na nb
O(na + nb)
O(log na + log nb) O(na log na + nb
log nb) O(1)