CS 117, Fall 1999

Assignment 3: Data Processing, due gradually

You may work with a partner for this assignment. No groups of three or more, please.

When you are done with each phase of this assignment, please submit your code using the Homework Submission Program.

The Goal

In this multi-stage project, you will develop a program that does the following:
  1. Asks the user for an input file name and two output file names.
  2. Reads lines of the form "Name score score score score...score" from the input file and stores them in appropriate variables. (The scores on these lines might represent test scores or bowling scores or white blood cell counts--for our purposes it won't matter. What will matter is that the scores will all be integers, and that each line will have one name and 10 scores.)
  3. Sorts the data alphabetically by name, and writes lines of the form "Name average" to the first output file.
  4. Sorts the lines in decreasing order of average scores, and writes lines of the form "Name average" to the second output file.
  5. Prints a summary of the data to the screen: the number of lines of input, the overall mean of all the scores, and the mean and maximum score for each of the 10 tests/bowling games/blood tests.
For example, suppose the input file contains 


Norma 6 12 8 9
Stu 5 5 5 5
Abby 3 9 6 4


(simplified to four scores per line for this example). Then the first output file will contain 


Abby 5.5
Norma 8.75
Stu 5


and the second output file will contain 


Norma 8.75
Abby 5.5
Stu 5.


Finally, the summary printed to the screen will say something like 


Number of people: 3
Mean score: 6.42
Test #1: mean 4.67, maximum 6
Test #2: mean 8.67, maximum 12
Test #3: mean 6.33, maximum 8
Test #4: mean 6, maximum 9


You will develop this program in relatively small steps, handing in your code after each step.

Stage 1 : due 8:30AM Monday, 10/25/99

Write a program that:

  1. Asks the user for the name of an input file and an output file. The input file will consist of a list of no more than 100 names, one per line. Each name will consist of letters only, with no spaces or punctuation.
  2. Reads the names into an array of string variables.
  3. Sorts the names.
  4. Writes the names in sorted order, one per line, to the output file.

Stage 1.5: due never

Write a program that does the same thing as the Stage 1 program, but instead of reading the names into an array of string variables, read the names into the "name" fields of an array of structs defined like this: 


const int scoresPerPerson = 10;

struct Person
{
    string     name;
    int        score[scoresPerPerson];
};


Then, instead of sorting an array of string variables, you're sorting an array of Person variables. Otherwise, everything stays the same as in Stage 1.

Stage 2: due 8:30AM Friday, 10/28/99

The input file will now contain lines consisting of a name followed by ten scores. Write a program that

  1. Asks the user for an input file name and an output file name.
  2. Reads the data into an array of structs as shown in Stage 1.5 above.
  3. Sorts the array alphabetically by name.
  4. Writes the names and average scores to the output file.


Stage 2.5: due never

Add a second output file and sorting by average score to the Stage 2 program.

Stage 3: due 5:00PM Monday, 11/1/99

The final program, including the second output file and the on-screen summary, as described above.

Some unsolicited advice

Make a plan in prose or pseudo-code on paper before you start coding. When you start coding, write the code on paper before going to the machine.

Plan a sequence of smaller programs building up to each stage's final version. For example, for Stage 1, you could (1) get the program to read the names from the file and print them directly to the screen, unsorted, (2) get it to store the names in an array, and then print them to the screen, unsorted, (3) get it to store the names in an array, and then write them to the output file, unsorted, and finally, (4) get it to do the full Stage 1.

Every time you get a program that does what it does correctly, save a copy of it and don't touch the copy any more.

Delete executables so you don't get nasty automatic e-mail telling you you're over quota.

If you're stuck, don't suffer too long in silence. Talk to me or Robin Smogor or a lab assistant or a friend.

Start early, keep in touch, and have fun.


Jeff Ondich, Department of Mathematics and Computer Science, Carleton College, Northfield, MN 55057
(507) 646-4364, jondich@carleton.edu