CS
3050, Spring 2007
Programming Assignment 1
Due Wednesday, February 28, 2007
Longest Line
This lab is designed to ensure that you are familar with C++ classes,
while applying some of the file processing operations we have
seen in class.
- C++ modules and methods you may want to review
- string
- iostream
- fstream
- main
- getline
- open
- close
- C/C++ reference: http://www.cppreference.com/
Task:
Write a C++ program that
- reads an input file in text
(ASCII),
- finds the longest line in the file,
- prints the length and
contents of the longest line to the screen,
- writes the length and longest line to a text
(ASCII) file.
Your program should be well documented and written in good style. To
document the program, write comments explaining what is done in the
following lines and add comments at the end of certain lines explaining
what has been done on that line. For each function or method add a full
explanation before it, explaining the purpose and what the parameters
represent, pre- and postconditions. For each class created, add an
explanation before it. Good
style includes good documentation, choice of clear variable names, and
good program organization and design.
SPECIFICATIONS
Lines:
Lines in the file will be delimited by newline ('\n') characters.
Command line arguments:
The input file (or files) for your program will be given on the command
line. The main mechanism to do this involves the use of the following
arguments in the main program:
int main(int
argc, char* argv[])
(You may want to look up information on these parameters in your
favorite C++ book or on the web.)
Structure of your program:
Your program will consist of four files:
- main program (file: Lab1main.cpp)
- Line class (files: Line.cpp and Line.h)
- script (see "Making a script" below) - including compile line and
tests
The line class:
The line class should include the following methods:
- Constructor
- setData
- getData
- getLength
where the data (contents of the line) is private.
Testing your program:
Before submitting your program you should test it on a variety of
files, including but not limited to:
- Nonexistent file
- Empty file
- A .cpp file
- A regular text file
- More than one file, if you have provided for this in your program
The results of these tests should be reflected in your script.
Submitting your program:
You should submit the four files listed above in "Structure of
your program" and any test files referred to in the script.
Your files will be uploaded though our automated submission
system:
https://majord.csustan.edu/cshomework/
Go to this web site and login using your cs login name and password.
Select CS3050 and Lab1, follow the instructions to upload your
programs. (Note that the testing/compiling module may not be functional
at this time, so I will not be providing a compile line for you.)
Should you have any difficulties with the submission system, please
alert me as soon as possible. If the submission system fails, email
your files to me as attachments (mmartin@cs.csustan.edu).
Making a script (by Dr.
Sarraille)
Making a Record of a Program Run: Now that you are
sure the program is working correctly, let's
do another
test. This one will be "for the record." Enter "script p1.script"
and wait until the computer writes a prompt on the screen again. (There
may
be a slight delay. The prompt you get now may be different than
before.)
Here's an explanation of what you just did: The "script"
command
turns on a program that makes a record of whatever appears on the
screen. The
command you entered was "script p1.script" so the record the
script
program makes will be a file called p1.script.
Enter "a.out" and see your "Hello World!" message
written to
the screen again. Now enter "exit" to turn off the scripting
program. From the time you entered "script p1.script" to the
time
you entered "exit", all things that were written on the screen
were
also recorded in the file called p1.script.
Enter clear to clear the screen. Now enter "cat p1.script".
This causes the computer to type the contents of the script file you
made.
It should look something like this:
Script started on Sat Aug 21 19:05:11 2004
jdoe@vega:(~) a.out
Hello World!
jdoe@vega:(~) exit
script done on Sat Aug 21 19:17:37 2004
Note that the script file (named p1.script) starts and ends with
"timestamps"
that tell when the script was started, and when it was completed. In
between
it reproduces what you typed.
Now enter "jove p1.script" so you can look at the file with
the JOVE
editor. You see your script. You also see "weird" characters in the
script
like ^M at the end of each line, and maybe some other things. These
characters are an undesirable side-effect of the way the scripting
program
interacts with special characters that handle the terminal display. The
weird
characters are sometimes visible, and sometimes not, depending on just
how you
try to display your script file. The characters were not visible when
you
displayed p1.script with "cat," but they were visible when you
used
JOVE. Do a C-x C-c command to exit JOVE.
When you turn in a real programming
assignment, you will be sending me the
source code, plus a script similar to the one you just made. The script
will
be a record that will show me that you did the right kind of testing of
your
program.
I require you to run your script through a filter before you send it to
me.
It's a way to get rid of most of the weird characters, so the script
will be
more readable. It is easy to do, no matter how big the script is.
Here's how: Enter "cat p1.script | col -b
>
temp". This command pipes the script file to the input
of the
command "col -b > temp", which filters out some of the
weird
characters and writes the output to a file named temp. Now the temp
file is
the filtered version of the script. Enter "mv
temp p1.script" to replace the script file with the new
filtered version. Now enter "jove p1.script" again. See how
the
file has been cleaned up? Good. Exit JOVE again by doing a C-x C-c
command.