----- Original Message -----
From: ""zhihua li"" <[EMAIL PROTECTED]>
Newsgroups: perl.beginners
To: <beginners@perl.org>
Sent: Monday, October 23, 2006 9:05 PM
Subject: count the characters between the matches
hi netters,
I'm curious if there's any smart code to calculate the "distance" between
the matches in a text.
Suppose I have a text like this:
syhk...yes...uhg;ka=...yes...yiealg.....yes.......ghe;a...yes...
Apparently it has multiple words of "yes". I'd like to know how many
characters there are between the first and the last "yes". The way I now
come up with to do this is to use substitution to "mark" the first and the
last match, then use a counting loop to calculate the
characters......rather straightforward and stupid method.
Anyone has a better idea about that?
Thanks a lot!
This will give the result you want.
#!/usr/bin/perl
use strict;
use warnings;
$_ = 'syhk...yes...uhg;ka=...yes...yiealg.....yes.......ghe;a...yes...';
if (/.*?(yes).*(yes)/) {
print "position at end of first yes is $+[1]\n";
print "position at beginning of last yes is $-[2]\n";
print "number of characters between first and last is ", $-[2] -
($+[1] -1 );
}
**prints
position at end of first yes is 10
position at beginning of last yes is 58
number of characters between first and last is 49
Chris
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