my %OldFile;
for my $file (@OldPicList) {
  $file =~ s{^\s+|\s+$}{}g;
  $oldFile{$file} = 1;
}
my @NewPicFolders;
for my $file (@NewPicList) {
  $file =~ s{^\s+|\s+$}{}g;
  if ($oldFile{$file}) {
    # nothing
  } else {
    push @NewPicFolders, $file;
  }
}