Due date: 8:00 A.M. Monday, October 6th

1 Purpose

You are running a ``Couples Counseling'' service. Troubled couples come to you for therapy that they hope will save their relationship! This program will prompt the user to enter today's date, the birth date of the user and the birthdate of the user's partner. It will then determine how much therapy (if any) the couple will need to get better. (It's amazing how this can be done by just knowing the birthdays of the people involved!)

2 Project description

You might want to begin by looking at the ``Sample Run'' section at the end of this document.

2.1 Input

The program begins by printing a cheerful message:
Welcome to the Couples Clinic.  We are here to help.
Next the program prints a blank line, then prompts the user for today's date, the user's birthdate, and the birthdate of the user's partner. Note that each date is entered as three individual integers. Here is an example:
Enter today's date (mm dd yy): 9 27 03
Enter your birthday (mm dd yy): 8 21 83
Enter your partner's birthday (mm dd yy): 5 3 79
Here, the user has specified that today is September 27th, 2003. His/her birthday is August 21st 1983, and his/her partner's birthday is May 3rd, 1979.

2.2 Processing

2.2.1 Generations

The first thing the program will do is find out what ``generation'' the couple is part of. People born before 1938 are considered ``senior citizens''. People born from 1938 to 1967 are considered ``baby boomers'', and people born 1968 or after are considered ``generation X''. If it turns out that the two individuals are not from the same generation, then your program will determine that they are fundamentally incompatible, and will print a blank line, followed by the message:
You are from two different generations!  Just break up.
In this case, the program should then terminate without printing any further messages.


Assuming that both people are part of the same generation, the program will print a blank line, followed by one of the following messages, depending on the generation:

You're Senior Citizens!  I am certain that I can help you folks.

You're Baby Boomers!  Chill out, I can help you, man.

You're Gen-Xers!  Dude, I can like TOTALLY help you.

2.2.2 Compatibility

If both partners are in the same generation, then an extensive calculation will be performed that will determine how compatible the couple actually is. We will use the following terms to discuss how compatible a couple is:
  1. Good Karma. Couples who are born in adjacent months have good karma. (The year in which they were born is not important.) For example, if one partner was born March 1955, and the other was born April 1960, they have ``good karma'' because March and April are consecutive. (We will consider December and January as consecutive also.) Note that couples born in the exact same month do NOT have good karma.
  2. Bad Karma. To determine whether or not a couple has ``bad karma'', begin by finding the sum of the dates of their births. Here we are only concerned with the day, not with the month or year. For example, if one person's birthday is September 14th, 1982 and the other's is February 27th, 1979, we would add 14 + 27 and get a sum of 41. If this sum is divisible by 7, 13, or 3, then the couple has ``bad karma''.
  3. Bad Age Separation. If the years in which the partners were born are more than 6 years apart, this is considered a ``bad age separation''. Note that the month and day of birth is irrelevant, just compare the years. For example, 1960 and 1967 are more than 6 years apart, even if one partner was born at the end of 1960 and the other was born at the beginning of 1967.
  4. Good Age Separation. (First read the paragraph above). If the difference in years (computed as above) is 2 or less, then the couple has ``good age separation''.
  5. Good Synchronization. First add together the values for month, day and year for each partner. If these two sums both end in the same digit, that is ``good synchronization''. For example, if the birthdays are February 9th, 1967 and April 15th, 1969, the sums both end with the digit '8', so these people have ``good synchronization''.
  6. Bad Synchronization. Take a look at the very last digit in the ``day'' of each person's birthday. We are ignoring the month and year. If these digits match, then the couple has ``bad synchronization''. In other words, if one person is born on the 13th and the other on the 23rd, then they have ``bad synchronization''.
Note that the categories above are never mutually exclusive. For example, it is possible for a couple to have both ``good synchronization'' and also ``bad synchronization''. We will calculate the compatibiltiy of the couple as follows. The couple starts off with a base compatibility rating of 0. This is adjusted by adding or subtracting amounts as described below: Adjust the couples compatibility index by adding or subtracting any of the items on the list above that fits. For example, a couple who are Baby Boomers with Good Age Separation, but with Bad Synchronization would get a compatibility rating of -3.

2.3 Additional Output

There must be a blank line between the ``I can help you'' greeting and the rest of the output. There must be a blank line between each subsequent line of output.


If the couple's compatibility index is greater than or equal to zero, then print the following message:

Your compatibility index is %d.  You don't need my help!
(where %d is the compatibility index.)


In this case, the program should terminate without further output.


On the other hand, if the couple's compatibility rating is less than zero, then it dictates how many days of therapy they will need. For example, if the rating is -6, then the couple will need 6 days of therapy. For couples needing therapy, your program will print a line that says:

You will need %d days of therapy.  
(where %d is the number of days of therapy required.)


You must then calculate how long the couple will remain under your care, assuming that the therapy will start on today's date (which was entered by the user of the program.) For example, if the user entered the date March 6th, 2003, and the couple will require 8 days of therapy, then their therapy will end on March 14th, 2003. You will then print a line that says:

You will remain under my care until mm/dd/yy.
where ``mm'', ``dd'', and ``yy'' represent the month, day and year of the end of therapy. (In the example from the paragraph above, you would print the date as 03/14/03. Note that we insist on printing exactly 2 digits for each of the three fields.

2.3.1 Days in each Month

You will need to know how many days are in each month in order to calculate the end of therapy date. For example, if you begin therapy on September 27th, and you need 6 days of therapy, you won't finish until October 3rd. This relies on knowing that September has 30 days. The following chart will help: You may ignore leap years or any other periodic calendar adjustments in the date calculations.

Days in each Month
January 31
February 28
March 31
April 30
May 31
June 30
July 31
August 31
September 30
October 31
November 30
December 31

3 Project requirements

All your C programs in this course should be written in ANSI C with trapping of unintialized variables, which means they must compile and run correctly with cc -std1 -trapuv on the OIT UNIX Class Cluster. Even if you already know what they are, you may not use any C language features other than those introduced in Chapters 1 through 5 of your textbook. Note that loops, arrays, and user-defined functions may not be used. In addition, your program must contain only one single return statement at its end. Using C features not in these chapters will result in losing credit. Your program must have a comment near the top which contains your name, login ID, student ID, your section number, your TA's name, and an original description of the action and operation of the program. Your program should be written using good programming style and formatting, as discussed in class and throughout your textbook. For this project, style is considered to consist of:

4 Primary Input/Output

We have provided two files (primary_input and primary_output) to help you test your program. If your program is run using the file primary_input as the data source, then the output should look exactly like the file primary_output. You can use UNIX redirection and the diff command to check your program with this sample data. Here's how:
  1. Compile your program - let's suppose the executable is called a.out
  2. Run your program using primary_input as the data source, and another file for the output. We'll suppose the other file is called myoutput: % a.out < primary_input > myoutput
  3. Check to see if your output file matches the primary_output file: % diff -bwi myoutput primary_output
If your output is correct, the diff command should generate no output of any kind. If your output is different from the primary_output file, the diff command will show you what lines are different. Important: We will be testing your program with many different data sets, not just the primary_input mentioned above. You will lose substantial credit for each test case that your program does not handle correctly. For this reason, it is very important that you test your program with a wide variety of input data.

5 Developing your program

You may want to skip this section at first, read the rest of the project, and come back to study it carefully when you are about to begin writing your program.

5.1 Program Development

It is very important to continue to type in only a part of your program at a time and verify that it's correct, before going on. Any mistake is much easier to locate this way. The idea is that at all times you have a correct program, which may be incomplete and solve only part of the problem but at least the part you've written so far works. In other words, do not attempt to write your program to perform all the necessary tests or produce completely correct output at first. Add code to perform only one processing step at a time and produce its output, and then add another until your program is complete.

5.2 Finding compilation errors

  1. As before, if you get the error ``Invalid statement'' and the compiler identifies the very last line in your program, it usually means you have mismatched braces. Carefully match up all of your braces, and make sure that there is a closing brace to match every opening brace. This is much easier to do using a printout, and is far easier when your program is formatted neatly using proper indentation and placement of braces. Draw a line pairing up each set of matching braces until you can tell where one is missing.
  2. If you get the error ``Invalid statement'' and the compiler points right to an else, the else is not placed so it's inside an if statement. Only one statement can appear as the subsidiary statement after an if, and only one statement can appear after an else. If you want more than one statement to appear in a place where one statement belongs, you can use braces to group them into a compound statement. You may have forgotten braces around the statements which were supposed to be executed if the condition in the if/else was true (the first group of subsidiary statements). Alternatively, it's possible you made a mistake and have more elses than ifs. You are much less likely to make this mistake when your code is properly formatted and indented, with each else lined up to clearly indicate which if statement it belongs to.

5.3 Program debugging

If your program doesn't produce the results you think it should, the debug printf statement is the best tool you can use. If, for instance, you're not sure why one branch of an if/else statement is being executed when you think the other should be, put a debug printf statement right before the whole if statement which prints the values of all the variables used in the condition. Maybe one of them doesn't have the value which you think it should have at that point. On the other hand, if you run your program and see that the variables all have correct values, then the condition itself is probably not expressed correctly. Or perhaps nothing prints in some case where you think something should. Try adding an else to every if statement which doesn't already have one, which prints a message indicating what must be true for that statement to be printed. Also in other cases, add as many printfs as you need to determine what is true about the data currently stored. Make sure the debug printfs you add are descriptive in nature to tell you any information you may need to determine what your program is doing, such as what line in in the program is producing this output or what the values of all relevant variables are at that point. This is much more useful than printing something like ``I am here'' in your debug printfs. Also, make sure the debug printfs do not change what statements are controlled by the if or the else. Also for technical reasons not worth explaining, it is very important that every debug printf ends with the newline character '\n'. Although these debug printfs will make your output look incorrect, they will help you develop your program correctly. Make sure that all debug printfs are removed before you submit your source code file for grading. After removing them, before submitting your source file, make sure that you have compiled, run and tested your project again to be sure you did not accidentally change it when you were removing those lines. If you can't find the problem after trying to debug your program using these techniques, bring printouts of your program and any compiler errors or execution results to office hours. To help us find the mistake as quickly as possible, be prepared to demonstrate and explain how you have tested your program, and what results you got.

5.4 Program testing

It is very important to test your program against all different possibilities of input data, not just those provided by us. Doing this correctly involves thinking of what other input values are possible based on the project description, and what results the program should produce in those cases. As an example, say you had to write a program which reads three integers into variables a, b, and c, and prints the name of the variable which had the largest value. Imagine that you wrote the following program:
#include <stdio.h>

main() {
  int a, b, c;
  scanf("%d%d%d", &a, &b, &c);

  if (a <= b) {

    printf("b");

    if (b <= c)
      printf("c");

  } else printf("a");

  printf("\n");
  return 0;
}

Try typing, compiling, and executing this program. If you run the program and enter 2 6 4 it prints ``b'', which is correct. If you run it and enter 6 4 2 it prints ``a'', which is correct. You might assume the program works since you ran it twice with different input values, but it is not correct. Try entering 4 2 6 and it prints ``a'', which is wrong. Try entering 2 4 6 and it prints ``bc'', which is also wrong. There are other possibilities of input values which cause incorrect results as well. The conclusion is that it is always necessary to think of all the different possible combinations and possibilities of input values which might appear in a program's input, and test it so you are certain it works correctly in all cases, not just for one or two different inputs. If you are curious, one correct program to perform this task is as follows. The program could also be written using the logical operators.
#include <stdio.h>

main() {
  int a, b, c;
  scanf("%d%d%d", &a, &b, &c);

  if (a <= b)

    if (b <= c)
      printf("c");
    else printf("b");

  else

    if (a <= c)
      printf("c");
    else printf("a");

  printf("\n");
  return 0;
}

5.5 Helpful hints

One development policy which is extremely important is to use proper indentation from the beginning. Many students type in their programs any way at all, with poor or no indentation, figuring once their project works correctly they will clean it up before submitting it. This is a very bad idea, because it is much harder to find certain errors in a program with poor indentation, and it's much easier to make these types of mistakes. You are much more likely to have problems such as mismatched braces, or misplacing an else, or misunderstanding which statements are subsidiary to which if statements if your code is improperly formatted or indented, or the braces are incorrectly placed. If you come to office hours for help with a program which has missing or very poor indentation, you will be asked to correct and reformat your program before we are able to help you further with it.

6 Academic integrity statement

Any evidence of unauthorized use of computer accounts or cooperation on projects will be submitted to the Student Honor Council, which could result in an XF for the course, suspension, or expulsion from the University. Projects are to be written INDIVIDUALLY. For academic honesty purposes, projects are to be considered comparable to a take-home exam. Any cooperation or exchange of ideas which would be prohibited on an exam is also prohibited on a project assignment, and WILL BE REPORTED to the Honor Council.


VIOLATIONS OF ACADEMIC HONESTY INCLUDE:


  1. failing to do all or any of the work on a project by yourself, other than assistance from the instructional staff.

  2. using any ideas or any part of another student's project, or copying any other individual's work in any way.

  3. giving any parts or ideas from your project, including test data, to another student.

  4. having programs on an open account or on a PC that other students can access.

  5. transferring any part of a project to or from another student or individual by any means, electronic or otherwise.


IT IS THE RESPONSIBILITY, UNDER THE UNIVERSITY HONOR POLICY, OF ANY STUDENT WHO LEARNS OF AN INCIDENT OF ACADEMIC DISHONESTY TO REPORT IT TO THEIR INSTRUCTOR.

7 Submitting your project

No projects more than two days late will be accepted for credit without prior permission or a valid medical excuse, as described on your syllabus. Only the project which you electronically submit, according to the procedures provided, can be graded; it is your responsibility to test your program and verify that it works properly before submitting. Lost passwords or other system problems do not constitute valid justifications for late projects, so do not put off working on your program or wait to submit it at the last minute! Turn in your assignment using the ``submit'' program as before, except using ``2'' for the project number. You are to submit only the .c file containing your source code, not the executable version of your program! If your program is in a file named ``p2.c'', submit would be run as shown.

% submit  2  p2.c

8 Sample Run

Welcome to the Couples Clinic.  We are here to help.

Enter today's date (mm dd yy): 9 26 03
Enter your birthday (mm dd yy): 11 3 78
Enter your partner's birthday (mm dd yy): 5 6 75

You're Gen-Xers!  Dude, I can like TOTALLY help you.

You'll need 5 days of therapy.

You will remain under my care until 10/01/03

About this document ...

This document was generated using the LaTeX2HTML translator Version 2K.1beta (1.61)

Copyright © 1993, 1994, 1995, 1996, Nikos Drakos, Computer Based Learning Unit, University of Leeds.
Copyright © 1997, 1998, 1999, Ross Moore, Mathematics Department, Macquarie University, Sydney.

The command line arguments were:
latex2html -show_section_numbers -split 0 -no_navigation -no_footnode p2

The translation was initiated by Fawzi Emad on 2003-09-26


Fawzi Emad 2003-09-26

Web Accessibility