You just need to adjust the regex a little.

my @array_codes = split /\s+/, <FILE>;
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assumes that you're interested in all non-whitespace characters. Changing it to:

my @array_codes = split /\W+/, <FILE>;
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means that your're only interested in non-word characters (where word chars are A-Z, 0-9 and '-').

Perl Training in the UK <http://www.iterative-software.com>

Hi, you have two options. If you wish to retain ultimate control split on whitespace and filter the elemets in @array_codes using this (as above)

$code_key =~ s/[.?!:;"'()]//g;
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This filters out all the stuff in the char class. Alternatively you can just grab alphanumerics in the first place like this:

@array_codes = <DATA> =~ m/\w+/g;
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cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

I followed your instructions, and I used:

open (FILE, "file.txt") || die "Can't open data file.";

while (<FILE>) {
   @array_codes = split /\W+/;
   foreach $code_key (@array_codes) {
           $codes{$code_key}++;
           } 
}
printf "$_\t$codes{$_}\n" for keys %codes;
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everything is outstanding, BUT the function also calculated the blank lines between the paragraphs. It outputed something like:

     12
ab   42
aba  25
.......
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I tried s/\n/ /g, but it still counted the blank lines. How do I get rid of the blank lines in a txt documents, and relace them with a space? Or there is a way to not count the blank lines? Thank you very very much...

As noted by MeowChow the devil is in the details:

#!/usr/bin/perl -w
use strict;

my %codes;

open (FILE, "file.txt") || die "Can't open data file, perl says $!";

while (<FILE>) {
   my @array_codes = /[A-Za-z0-9]+/g;
   foreach my $code_key (@array_codes) {
       $codes{$code_key}++;
   } 
}

print "$_\t$codes{$_}\n" for sort keys %codes;
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This will get groups of chars that match A-Za-z0-9 only and then prints out the sorted hash. I have added the $! var in the die which contains Perl's error message and sort the keys. I have added us strict, -w and the my declarations. Also note that printf was a typo. I meant print.

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print