use strict; use warnings; use Digest::MD5; use Cwd; use File::Find; my $dir = getcwd; my @files; find(\&get_dir,$dir); for my $file(@files)  {   print $file,"\n";   my $md5 = Digest::MD5->new;     open FILE, $file;   binmode(FILE);   while() { $md5->add($_); }   my $digest = $md5->hexdigest;   close FILE;   print "Digest is $digest\n"; } sub get_dir  {   push(@files,$File::Find::name) if(-f $File::Find::name);   }