#!/usr/bin/perl

use Date::Manip;

$date_2_days_ago = ParseDate("3 days ago");;
$date_converted = UnixDate($date_2_days_ago,"%e/%h/%Y");

open DATA,">$ARGV[1]";
open FH,"$ARGV[0]";

while(<FH>){
  @tab_delimited_array = split(/\t/,$_);
  $tab_delimited_array[3] =~ s/^\[//;
  $tab_delimited_array[3] =~ s/^\-//;
  chomp($tab_delimited_array[3]);

    if(length($tab_delimited_array[3]) > 1)
     {
     $date_format= UnixDate($tab_delimited_array[3],"%Y%m%d%H:%M:%S");
     $converted_date = Date_ConvTZ("$date_format",'GMT','PST');
     $pst_converted_date = UnixDate($converted_date,"%e/%h/%Y:%H:%M:%S
+");
     $pst_converted_date =~ s/^\s//g;
     $extracted_YMD=UnixDate($converted_date,"%e/%h/%Y");

         $_ =~ s/$arr[3]/$pst_converted_date/g;

if($extracted_YMD =~ m/$date_converted/){
        print DATA $_;
        }
    }
}

close DATA;
close FH;

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Please tell me how can i optimize this code. The file is very large and has around 11989364 lines. So the processing is very slow.

In reply to optimize the code by Anonymous Monk

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