grader

(Latest Revision: 11/19/2001)

SIXTH CS 1500 SOLO PROGRAM: Grading Program

OBJECTIVE: The purpose of this programming assignment is to get practice using files, arrays, and for-loops.

THE ASSIGNMENT:

Write a program that grades a multiple choice exam.

INPUT:

You must write the program with certain facts, assumptions, and preconditions in mind:

The program gets all its input from a file named testData.
Generally, there is no way to know exactly what will be in the file testData when the program executes.
However we do have the assumption and precondition that the first line of testData is a key like this one:
```
     b b c b c d d c a d a d e c b e a d e b
```
The key can be any string of 20 lower-case letters separated by blanks. The key represents the set of answers to 20 multiple choice questions.
We also assume that the second line of testData is a single non-negative integer -- call it numStudents. The number numStudents represents the number of students who took the test.
The final assumption is that there are numStudents more lines in testData following the second line. Each of those numStudents lines represents the answers given on the test by one student.

When the program runs, the file testData could be any file that conforms to the rules above.

Example #1


a e c b b b a e a d e a a d e a c d b b
3
a e e a b c a b a b c c a a b e d d d d
b e a b c b e a e c d b b d d e c e b c
a e a b b b a b a d e a d d e a a d b b

Example #2


d d e d b a d b c e e c b a a e a d b d
6
a a d e d b d a c b b a c a b d d e e c
a d a e d a d b a e e a b d c a b c c d
d b b a d c d b d c e d b e c b b d c d
e c b d c d d d a a d a b e d c b b a b
b e a e a e a d e a e b e a e d a c b c
e b e d b c a e b a b c c d d e c a a e

six

Your program must correctly process the contents of testData, whatever its contents turn out to be.
When I test your program, some of the versions of testData that I test it on will be files I have never shown to you. If your program works incorrectly on any of my versions of testData, you will lose substantial credit.

You will need to use an editor to make versions of testData for your testing.

If you like, you may cut and paste sequences of letters from this file. I generated these letters by writing a program that uses the random() function.

OPENING THE INPUT FILE:

Your program will open testData with this statement:

ifstream infile("testData") ;

OUTPUT:

The program counts how many correct answers each person got. The program prints a simple tabular report. Here is how the report must appear if example #1 above is the contents of testData:


Student Number      Number Correct       PASS/FAIL

       1                  7                FAIL
       2                  6                FAIL
       3                 16                PASS

Of course, what will be seen in the report will depend on what is in testData.

The column headings must be as shown. The spacing does not have to be identical, but the report must be very tidy and readable.

The student numbers, from 1 to numStudents, must appear in the first column. (Sorry, but it is not OK for the numbering to start at 0, even though C++ arrays start at index zero. You must be careful to adjust the numbering.)

The next column must show the number of correct answers for each student.

The last column contains the word PASS or FAIL, depending on whether the student got 60% or more correct.

THE DESIGN OF THE PROGRAM:

There must be at least three functions in the program (including main). There must be at least two functions that have one or more parameters. You may find you get a better design if you use more than three functions.

You must create your own design of this program. I am expecting you to employ good principles of top-down design. Substantial credit will be withheld if you do not create a program that uses functions appropriately.

Some particulars:

Make sure that each function does one thing well.
Put no more than one return statement in any function.
Use exit() statements sparingly -- no more than one in each function.

I want you to get the experience of writing a program that uses an array. Therefore I am requiring that your program use an array to store the key. You may use more arrays if you wish.

Because I am going to test all the programs by compiling and running them on different versions of the input file, I need everyone in the class to use exactly the same name for the input file. Therefore, please name your file testData and use the command:

ifstream infile("testData") ;

in your program.

To see some C++ code with similarities to the code you need to write, look at the sample program that reads and prints golf scores. Note: Come to class to get more discussion of how to design the program.

FORM AND FORMATTING REQUIREMENTS:

Write appropriate header comments for each of your functions. Header comments are the comments that appear at the beginning of the function, telling what it's purpose is and what the preconditions and postconditions are, and so forth. You may pattern your header comments after the example code in your text book, or you may use this information as your guide.

At the beginning of your program file put a header comment like this:


  /* PROGRAM Batting Statistics */

  /*

  Name:          Gordon Goodguy
  User Name:     goodge
  Course:        CS 1500, Computer Programming I
  Instructor:    John Sarraille
  Date:          January 01, 1970

  */

Of course, in place of "Gordon Goodguy," you must put your own full name. In place of "goodge" put your user (login) name. In place of "January 01, 1970" put the date that you finished the program. Note that the comment delimiters /* and */ are important. They need to be placed correctly or you will get compiler errors.

TESTING:

Since the specifications allow numStudents to be zero, you will need to make at least two versions of testData for testing.

Here's a nice way of managing different versions of testData for testing:

Make a file in which numStudents is zero, and call it testData01.
Make an "average" version of a testData file and call it testData02.
When you want to run the program with testData01 as the input, just do the command
```
cp testData01 testData 
```
first.
Similarly, when you want to run the program with testData02 as the input, just do the command
```
cp testData02 testData
```
first.

WHAT TO TURN IN:

Before midnight on the due date, e-mail the following two items to me:

A copy of the source code, properly documented.
A filtered script showing an appropriate number of test runs with appropriate inputs.

My e-mail address is: john@ishi.csustan.edu

Please use the following subject lines exactly for the e-mails:

For the source file: CS1500_Solo6_Source

and for the script file: CS1500_Solo6_Script.

Note that there are no spaces in these subject lines. If you like, you can copy and paste the subject lines right from this document.

Thanks! Your use of these subject lines will really be a big help to me when I try to sort through the perhaps hundreds of e-mail messages that will be in my electronic mailbox!

WHEN IS THIS ASSIGNMENT DUE?

Look for the due date in the class schedule. (It's at the top level of the class directory.)