ANOTHER SAMPLE ASSIGNMENT PART-I: Point of Sale Terminal (12 marks)

Transcription

ANOTHER SAMPLE ASSIGNMENT PART-I: Point of Sale Terminal (12 marks)
300580 – Programming Fundamentals
ANOTHER
SAMPLE ASSIGNMENT
Post of Sale Terminal
PART-I:
Point of Sale Terminal (12 marks)
You are required to design a program post.cpp (point of sale terminal) that
will be used to calculate the total cost for a list of purchased items against a
list of product prices. Each purchased item will be presented by its productId,
the price per item, and the corresponding quantity. The program is expected to
be interactive and the user can enter everything line by line and generate such
as an invoice at the end. We note that such an application usage can be
alternatively illustrated by piping all the data to the program. Suppose all the
program control commands and the data for the products and purchased items
are stored in a plain text file datafile.txt in the form similar to the following
sample
/rawprices
P010001
QX-35
DVD-player5
P010002
P010003
24.99
19.99
58.95
8.85
35.00
/items
P010001
DVD-player5
P010002
2
1
20
/invoice
/quit
where in a typical data line (blank lines are ignored), the first column
represents the product ID which will be alphanumeric without white spaces,
the second column represents the product price in Australian dollars when
inputing product prices, and will represent the quantity of the corresponding
purchased item when inputing purchased items. Your program post.exe
compiled from post.cpp will then be able to generate an invoice via
post.exe < datafile.txt > invoice.txt
whose output invoice.txt could look like
PHANTOM COMPANY INVOICE
PRODUCT ID
P010001
DVD-player5
QUANTITY
2
1
PRICE ($)
24.99
58.95
COST ($)
49.98
58.95
P010002
...
20
8.85
177.00
TOTAL COST = $xxxxx.xx
When the post program is executed, it will process commands and data
records entered by the user. If a word read into the program starts with the
character "/", possibly when the programming is attempting to read in a
product ID, then the word is deemed a program command. This program
should support at least the following commands
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/rawprices: this indicates that the data records to follow, if any, will be
for the product pricing in the form of
productId
price
/items: this indicates that the data records to follow, if any, will be for
the purchased items in the form of
productId
quantity
/invoice: this generates the invoice on the purchased items already read
into the program
/quit: this terminates the program
and any other words that start with the character '/' will be considered an
invalid command. For the convenience and uniformity of the program design,
we assume that the total number of different products will not exceed 2000,
and the total number of purchased items for each invoice will not exceed 1000.
The program should be designed in such a way that piping can also be used to
properly generate an invoice output as in the example at the beginning of this
document. Any explicit use of file inside the C++ program for this part will
not be considered a proper or complete solution in this particular assessment.
We note that if you are using prompts for interactive data input, you need to
make sure that the prompts are sent to standard error device using cerr
(instead of cout), i.e. using cerr in place of cout. This way, the prompts will
not be piped into the output file, say, statement.txt.
For the solution of this part, the students are required to provide
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the defining diagram (IPO chart) - 2 marks
the structure chart (hierarchy chart) - 2 marks
solution algorithm in pseudocode (don't use the C++ constructs: no
break, no return statements for instance) - 2 marks
complete program in C++ (including naming, style etc) - 3 marks
proposed testing cases with expected results for checking - 1 mark
desk checking a typical case - 1 mark
general design quality, error reporting, feel and robustness - 1 mark
NOTE: For this part, students may assume that the data records are line based,
as described in Part-II below, if they so wish. For the pseudocode part,
students may assume that all data that are fed to the program will be in correct
format. For the C++ program, however, some kind of additional error
reporting is required.
PART-II:
Extended Post of Sale Terminal (3 marks)
This part is merely an extension of the program described in Part I. The
functionality of this extended C++ program, xPost.cpp, should support the
following additional commands
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Data records and commands to the program are always line based.
More precisely, each command and every record will be in the form of
exactly 1 textual line, in that any extra bits outside the data fields will
be ignored. For instance, if the user enters the following 3 lines when
reading purchased items
P010001
P010002
1
2
whatever
the "whatever" bits there will be ignored because a purchased item
record just needs the first 2 fields, the productId P010001 and the
quantity 2, so the rest of the same line is ignored. The next 2 lines
actually contain 2 bad item records because each single line contains
an incomplete record and is thus considered an invalid record. The
xPost program should skip such bad records with a warning message.
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/newprices: this does the same as /rawprices but is smarter in that
after obtaining a product pricing record from the user it first check if a
pricing record for the product ID already exists or not. If it already
exists, the new pricing record replaces the existing one; otherwise it
simply gets stored.
/read inputfile: this reads into the program all the lines from the file
named inputfile (the inputfile can be any file name in the form of a
single word, i.e. no white spaces are allowed in the file name) as if
they were directly entered by the user.
For this part, only the complete C++ program needs to be submitted by the
students. The program will be assessed not only for the correct functionality,
but also for the good design and proper module decomposition. It also takes
into consideration of the program robustness at handling unexpected situations.
If this part is only partially completed for certain relevant individual modules
(functions), then the driver program (the main( ) function) should be designed
to illustrate these modules properly.
Note on Submission
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All C++ programs must be compilable under Dev-C++ ver 4.9.9.2,
or more precisely, under g++ 3.4.2 (mingw-special). For top marks,
good programming style and program design will also be considered.
This assignment must be submitted electronically via WebCT before
the due date. No email submissions will be accepted.
Submitted files may be zipped together as a single zip file, if a student
wishes to do so. However, no other file compression or file archiving
formats will be accepted for the submission.
The electronic submission should contain the paper work in plain text
or in Microsoft Word format, and the C++ source code (the .cpp file(s))
as well as other relevant files if any. Please do not include the
compiled executables as the markers will generate them for you
independently anyway.
Each submission must be accompanied by a declaration of the
ownership of the submitted work as described in the unit outline.
Please note that an examiner or lecturer/tutor has the right not to mark
this assignment if a pertinent declaration is not present in your
submission.
Late submissions will attract a daily incremented late penalty of 20%
per day.
Please note that if your C++ program does not compile, you
automatically lose 50% of the marks in the C++ coding part.
Electronic submission on the due date after 5pm before 12 midnight
will still be accepted without penalty. However, any submission failure
in that period due to either the student faults or the fault or malfunction
of the School's or UWS' servers will not be accepted as the legitimate
reasons for a late submission. Beware that School's servers often need
to be shut down for maintenance from late Fridays.