Hello. I wanted to create a perl script that removes all the duplicate lines from a file. So I searched on google for some scripts that do that. But they don't work properly. I need a script that removes all duplicates, but also the blank lines, spaces and tabs. Here's the script I've got now: 
use strict;
use warnings;
my $passwdfile = "d.txt";
my %seen = ();
{
   local @ARGV = ($passwdfile);
   local $^I = '.bac'; 
   while(<>){
         $_ =~ s/^\s+//;
      $seen{$_}++;
      next if $seen{$_} > 1;
      print;
   }
}
print "finished";

[download]
Input: 
5
5
5 

5

5

6


55

6
66

5
5
5 

5

[download]
Output: 
5
5 
6
55
66

[download]
I know it can be done with regex, but I'm a real beginner in perl and regex still looks very hard to me. Thx in advance

In reply to Duplicate lines with spaces, tabs... by marto9

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