CSCI 160 Assignment 4,   Fall 1996

This is a text version of the statement of the problem. A formatted
version has been distributed in class and is available under the CSCI
notice board (in the open-area outside my office).  If there is a
discrepancy between the text and formatted versions, the formatter
version will be used in order to judge your work.  

DUE:  
The assignment is due on or before 3am, Thursday October 31.  This
assignment is worth 20 objective points.  Your solution will be graded
on the basis of its run-time behaviour and on the clarity and
simplicity of the source code.  See the marking guide in
~csci160/Pex4/markingGuide. With regard to simplicity and clarity,
follow the ASAP principle: as simple as possible.

INSTRUCTIONS:
Issue the command:
               cp -r ~csci160/Pex4 .
to copy the assignment work directory to your account.  Locate to Pex4
and use the  CSCI 160 Exercise Development Utility to test, verify and
submit you assignment (enter the command  make help for instructions on
how to use the utility).

This assignment is to completed by each student.  Submit only one
implementation; if you send more than one, we will discard all but the
last one.  The assignment identifier is  CSCI 160 Pex 4 (see Course
Information Sheet).  Your assignment  must be received before the due
date and time.  In addition, your e-mail  must have the assignment
identifier as its subject.  All other methods of submission will not be
accepted.  You will receive no credit for an assignment submission that
fails to adhere to this convention.

QUESTION:
Description
Write a Pascal program that reads sequence of characters and determines
if the  sequence is a palindrome.  A palindrome is a word or phrase
that reads the same backwards as forwards.  Palindromes are NOT
sensitive to the following:
      - character-case
      - non-alphanumeric characters

Sample Output
Enter the sequence of characters:
Sequence must be terminated with a period (.)
Nurses run.
The sequence is a palindrome.

Enter the sequence of characters:
Sequence must be terminated with a period (.)
Nurses rum. 
The sequence is NOT a palindrome.

Assumptions 
You may assume that the end of the sequence to be tested is terminated
by a period (.).  The maximum number of alphanumeric characters in a
word or phrase to be tested is 255.  A palindrome has a minimum of 1
alphanumeric character.  You may not use string variables nor any
extended-Pascal string processing functions.  You may only use ONE
array and you must adhere to the parameter passing convention discussed
in class.

Test Set
Input                     Output
Word or Phrase            Palindrome (Yes or No)
Abba.                     Yes
ABBA .                    Yes
77 .                      Yes
;;;;++++ABBA++            Yes
....;;;;++++++            No
ABBb.                     No
Nurses                  
Run 
.                         Yes