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Expression Matching and Recursion

Posted by Eugene Teo on 1999-04-24

Hi

I am revising for my Advanced Data Structures module 
and i have got 2 important questions to ask. Please 
help.

Question 1:

How do i go about writing a function that accepts an
expression which is a string of characters and checks
for matching parentheses using Stack Operatings?
Also, besides parentheses, how do i go about writing 
a program that calculates expressions in the form of
maths formulas? eg: (a+b(c+7)). First it will match the
parameters, then it will calculate the values, assuming
a, b, c have values assigned to them. i understand that
i need 2 queues. please advise me and guide me with
this. i need to understand those which are more 
application-based.

Question 2:
I am supposed to write a recursive function but i tried
and think very hard yet, to no avail. The question is like
this: (Please teach me. I have some difficulty learning
recursive coz the the technique and the way it is program
is very different.)

A plaindrome is a string of characters that is the same when 
read forward or backward. Some examples of palindrones are:
"radar", "noon" and "level". Write a recursive function to
test a string in order to determine if it is a palindrome. Use
the function prototype as follows:

Boolean IsPalindrome(char *s);

Please answer my question and teach me how i should
approach the above questions and the topic on Recursion.
Thank you very very very much.

I really appreciate your help and time.

Eugene
--
eugeneteo@xxxxxxxxx.xxx.xx
http://amnesia.serverity.com.sg/