Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

alphanumeric - finding one less!

Posted on 2002-05-08
4
Medium Priority
?
196 Views
Last Modified: 2010-03-05
Hi

I need some help to chamge the end character in a string of letters to the character or number which is one less based on alphanumeric characters and maintaining case

example string 1 - " /YEZ/NOZ1/B2FREE/fixed "
example string 2 - " /YEZ/NOZ1/B2FRE3/fixed "

I want to become

example string 1 - " /YEZ/NOZ1/B2FRED/fixed "
example string 2 - " /YEZ/NOZ1/B2FRE2/fixed "

I have tried using "$string =~ s/$end/$end -1/"

but it doesn't work becase it is not a number and sometimes it finishes with "a letter/fixed" sometimes "a number/fixed"

"fixed" is the known string which is always constant...
"/APHANUM/APHANUM/APHANUM/" is the dynamic bit and it is always the character before "/fixed" that I need to be one less...

Can anyone tell me how to do it?

thanks

Jilly  
0
Comment
Question by:jillybabe
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
4 Comments
 
LVL 6

Accepted Solution

by:
holli earned 400 total points
ID: 6996554
this is one way:

$b="/YEZ/NOZ1/B2FREE/fixed";
$a="/YEZ/NOZ1/B2FRE3/fixed";

$a=~s|(.{1})/fixed|chr(ord($1)-1).'/fixed'|e;
$b=~s|(.{1})/fixed|chr(ord($1)-1).'/fixed'|e;

print "$a\$b";


regards,

holli
0
 
LVL 1

Expert Comment

by:japhyRPI
ID: 6998068
What should "BAA" decrease to?  "AZZ"?  And how about "FR0"?  That's a zero, so should it be "FQ9"?  We need more assistance with these boundary cases.  It's far easier to INCREMENT than to decrement.
0
 

Author Comment

by:jillybabe
ID: 6998242
Great that did it !

Thanks holli and you too japhyRPI

Jilly
0
 
LVL 1

Expert Comment

by:japhyRPI
ID: 6998715
Jilly, I'm just warning you that the current response turns "BAA" into "BA@", "FR0" into "FR/", and "STa" into "ST`".  To overcome these situations, you're going to need a slightly different regex.
0

Featured Post

Enroll in September's Course of the Month

This month’s featured course covers 16 hours of training in installation, management, and deployment of VMware vSphere virtualization environments. It's free for Premium Members, Team Accounts, and Qualified Experts!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Email validation in proper way is  very important validation required in any web pages. This code is self explainable except that Regular Expression which I used for pattern matching. I originally published as a thread on my website : http://www…
A year or so back I was asked to have a play with MongoDB; within half an hour I had downloaded (http://www.mongodb.org/downloads),  installed and started the daemon, and had a console window open. After an hour or two of playing at the command …
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
Six Sigma Control Plans

715 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question