#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;
##############

my $dir = "$ARGV[0]";
my %md5sum;
my @md5;
my $flag = 0;
my %seen;
opendir(my $dh, $dir) || die "Unable to Open the Directory: $!\n";
chdir $dir or die "Cannot Change directory: $!\n";
while (my $file = readdir $dh) {
    chomp $file;
    next if $file =~ /^\.+$/g;
    if (-f $file) {
        my ($md) = (split /\s+/, qx(/usr/bin/md5sum $file))[0];
        $md5sum{$file} = $md;
        push @md5, $md;
    }
 }
   closedir($dh);

my @uniq = grep { $seen{$_}++ } @md5;
foreach my $k (keys %md5sum) {
    foreach my $md (@uniq) {
	  if ($md eq $md5sum{$k}) {
	      $flag = 1;
	      last;
	  }
    }
    if ($flag) {
     print "$k is a duplicate file with MD5 of $md5sum{$k}\n";
	 $flag = 0;
   }else {
	  print "$k is not a duplicate file, It's md5sum is $md5sum{$k}\n";
   }
}

##</code><code>##

-bash-3.2$ ./duplicate_files.pl /users/scripts/perl/test/
file2 is a duplicate file with MD5 of d41d8cd98f00b204e9800998ecf8427e
file1 is a duplicate file with MD5 of 5bb062356cddb5d2c0ef41eb2660cb06
file3 is a duplicate file with MD5 of d41d8cd98f00b204e9800998ecf8427e
file4 is a duplicate file with MD5 of d41d8cd98f00b204e9800998ecf8427e
file5 is a duplicate file with MD5 of 5bb062356cddb5d2c0ef41eb2660cb06
file6 is not a duplicate file, It's md5sum is d617c2deabd27ff86ca9825b2e7578d4