hello , I use big txt file , i try this script it work but it is not fast : seq.txt contain sequence of words , I check for every sequence if it exist in mytext.txt then I attach the sequence with "bbb" . How can i make make this script fast mytext.txt (200 MB ) example : 
Many of them are scooped up by chambermaids, thrown into bin bags and 
+sent off to landfill sites, which is a disaster for the environment a
+nd a social travesty given that many people around the world are goin
+g without proper sanitation.

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seq.txt example : 
          scooped up by
          social travesty
          without proper sanitation

[download]
use strict;
use warnings;
use autodie;

open Newfile ,">./Newfile.txt" or die "Cannot create Newfile.txt";
 my %rep;
my ($f1, $f2) = ('seq.txt', 'mytext.txt');


open(my $fh, $f1);
my @seq;
foreach (<$fh> )
{
  chomp;
  s/^\s+|\s+$//g;
  push @seq, $_;
}
close $fh;

@seq = sort bylen @seq;  # need to sort @seq by length.

open($fh, $f2);
foreach (<$fh> ) {
  foreach my $r (@seq) {
    my $t = $r;
    $t =~ s/\h+/bbb/g;
   
    s/$r/$t/g;
  }
  print Newfile;
}
close $fh;
close Newfile ;
exit 0;

sub bylen {
   length($b) <=> length($a);
}

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In reply to script optmization by shoura

Title:
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