In this assignment you will write a program to manage the inventory and customers of the Acme Tool Rental
Company. Your program will handle several different operations: adding items to the inventory, renting tools
to customers, and handling returned items. Please carefully read the entire assignment before beginning your
The input for the program will come from two files, an inventory file and a customer file, and the output will
go to separate files for inventory and customers. These file names are specified by command-line arguments.
Here’s an example of how your program will be called:
rental.exe inventory_file customer_file inventory_output_file customer_output_file
The form of each input file is simple. Each line of the inventory file begins with an inventory ID which begins
with a T and is followed by a 4 digit integer.
Next is an integer quantity, followed by an item description.
You may assume the input file strictly follows this format, i.e., you don’t need to worry about format errorchecking. However, you should check for invalid IDs. If a line that does not begin with a T or does not have
a quantity greater than 0, print a message to std::cerr stating “Invalid inventory ID XXXX found in
the inventory file.” where XXXX is the invalid ID.
T1001 1 chainsaw
T3056 6 Floor_Jack
T2001 2 Roto_Hammer_1/2_inch
Each line of the customer file begins with a customer ID, a C followed by a 4 digit integer. Next is an action,
either the word rent or return, followed by a timestamp, a quantity, an inventory part number, and finally the
The time stamp is a four digit integer. You should check for invalid IDs, for example a line
that does not begin with a C. If you encounter an invalid ID, print a message to std::cerr stating “Invalid
customer information found for ID XXXX in the customer file.” where XXXX is the invalid ID.
C0029 rent 0935 1 T1001 Emma_Watson
C0010 rent 1000 1 T2001 Yogi_Berra
C0010 rent 1000 2 T3056 Yogi_Berra
In your program, you will create two classes, one for customers and one for inventory items. You will also
maintain two STL lists; an inventory list and a customers list. Do not use maps or any other structure
that hasn’t been covered in lecture. The inventory list should contain the items and the available quantity
of that item.
As customers rent or return the item, the quantity should be adjusted.
When a customer attempts to rent an item, check that sufficient quantity of the item is available. If there is
a sufficient quantity, rent the requested quantity of items to the customer and adjust the inventory quantity.
If the customer’s request cannot be filled, do not rent any item to the customer and add the customer’s
request to a wait list along with the timestamp.
If a customer requests an item whose inventory ID is not
in the inventory, print an error message to std::cerr stating “Customer CXXXX requested item TYYYY
which is not in the inventory.” CXXX is the customer ID and TYYYY is the inventory ID. You will
need to keep track of what items each customer rents and any pending items for the customer. You will also
need to keep track of which customers rent an item.
When an item is returned, adjust the available inventory quantity. Check the wait list for any customers
requesting the item. Attempt to fill the requests in timestamp order. If a customer on the wait list has
requested a quantity greater than the available amount, go on to the next customer. If the customer returning
the item has no other rental items or pending items, remove the customer from the customer list using the
STL list’s erase function.
The customer list should only contain active customers. If a customer attempts
to return an item that is not in the inventory, print an error message to std::cerr stating “Customer CXXXX
attempted to return item TYYYY which is not in the inventory.” CXXX is the customer ID and
TYYYY is the inventory ID.
If the customer returns an item that this same customer is waiting for, adjust
the inventory and customer’s pending quantity. If the customer has no rented or pending items, remove
the customer from the customer list. If the customer tries to return an item she has not rented, print an
error message to std::cerr stating “Customer CXXXX attempted to return item TYYYY which she/he
did not rent.”
The inventory list must be maintained in order by inventory ID. Similarly, the customer list must be
maintained in order by customer ID. You may not use the STL sort functions for this assignment. Use
the STL list insert and erase functions to maintain all lists in the proper order as you process each rental
or return event.
After reading the input files, produce a report of the current inventory and active customers. For each
inventory item, print the ID, the available quantity and the description as shown in the example below.
On the next line, if any customers are renting this item, print “Rental Customers” and then print the
customer IDs and names of customers renting this item, followed by the quantity that they have rented in
parenthesis as shown below.
If no one is currently renting the item, print nothing. On the next line, print
similar information for any customers waiting for this item including the quantity they have requested in
parenthesis. Here is an example of the format to follow:
T1001 0 available chainsaw
Rental Customers: C0009 Snoop_Dawg (1)
Pending Customers: C0001 Jane_Doe (1)
T2001 2 available Roto_Hammer_1/2_inch
Rental Customers: C0008 John_Snow (1) C0010 Yogi_Berra (1)
T2002 2 available Roto_Hammer_1_inch
The customer report is similar. It should contain a line for each active customer. An active customer is one
with rented or pending items. The line should begin with customer ID, name, followed by lines containing
rented items and quantities followed by lines for pending items and their quantities.
Here is an example:
Pending: T1001 (1)
Rentals: T2001 (1)
Rentals: T1001 (1)
Sample input and output files are posted on the course web site. Please follow these examples exactly to aid
in the automatic grading of your work. You can use the UNIX diff command to compare your output to
the sample output files.
You should implement the functionality above with efficiency in mind. In your README.txt file, use order
notation to analyze the computation needed for each stage of this program: loading the inventory, a single
rental event, a single return (with or without pending customers), and the overall cost of the entire program.
In your analysis, use these variables:
i = # of different inventory items
c = # of different customers
p = # of pending customers
q = max quantity of a particular tool owned by the store
r = max # of tools rented or requested by a customer at one time
p = total # of pending tool rentals
e = total # of rental or return events
Briefly justify your answers.
Additional Requirements, Hints and Suggestions
You may not use vectors, arrays, or the sort function for this assignment. Use the standard
library (STL) lists and iterators instead. You may not use maps, or sets, or things we haven’t discussed in
lecture yet. You must write at least two new classes: one for inventory and one for customers. You may
create additional helper classes.
Use good coding style when you design and implement your program. Be sure to make up new test cases and
don’t forget to comment your code! Please use the provided template README.txt file for any notes you want
the grader to read.
You must do this assignment on your own, as described in the “Academic
Integrity for Homework” handout. If you did discuss the problem or error messages, etc. with
anyone, please list their names in your README.txt file.
Extra Credit To encourage your fluency with the traditional step-by-step debugger we will post an additional
Crash Course in C++ module: ”Lesson 12: Debugger Use”. Completing this module before Friday March
3rd at 11:59pm will be worth a small number of extra credit points on Homework 4.