From: [EMAIL PROTECTED]
> I have a text file which contains a list of companies:
>
> NORTH DOWN AND ARDS INSTITUTE
> NOTTINGHAM HEALTH AUTHORITY
> 1ST CONTACT GROUP LTD
> 1ST CONTACT GROUP LTD
> 1ST CONTACT GROUP LTD
> 1ST CONTACT GROUP LTD
> 4D TELECOM & KINGSTON INMEDIA
> A E COOK LTD
> A E COOK LTD
>
> etc......
>
> How can a write a simple perl script to remove the duplicates and
> leave just one of each customer? Any help would be great.
Is it safe to assume that all duplicates are together like this? If
so all you have to do is to
1) read the file line by line
2) only print the line you just read if it's different from the last
one
3) remember the line
or if I word it differently.
1) read the file
2) skip the line if it's the same as the last one
3) print it and remember it
my $last = '';
while (<>) {
next if $_ eq $last;
print $_;
$last = $;
}
If the duplicates are scattered all over the place, then the easiest
solution is to use a hash, That will get rid of the duplicates for
you:
while (<>) {
chomp;
$seen{$_}++;
}
foreack my $item (keys %seen) {
print $item,"\n";
}
If the list of companies is huge you may need to store the hash on
disk to prevent swapping:
use DB_File;
tie %seen, 'DB_File', $filename;
...
Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
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