#!/usr/bin/perl
use strict;
use warnings;

my $start = ymd('01/02/2018');
my $end   = ymd('06/02/2018');
 
my $infile  = 'input.txt';
my $outfile = 'output.txt'; 
open IN, '<',$infile 
     or die "Could not open '$infile' : $!";
open OUT, '>',$outfile 
     or die "Could not open '$outfile' : $!";

my $count=0;
while (<IN>){
  if (/(\d{2}\/\d{2}\/\d{4})\s*$/){
    my $date = ymd($1);
    if ($date >= $start && $date <= $end){
      print OUT $_;
      ++$count;
    } else {
      print "$date Skipped : $_";
    }
  } else  {
    print "No date : $_";
  }
}
close IN;
close OUT;
printf "%d records written to '%s'\n",$count, $outfile;

sub ymd {
  sprintf "%04d%02d%02d",reverse split /\D/,shift;
}
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