# This is untested code!
my @dlcopy = @dir_list ;
my @extensions = qw(zip log whatever) ;
my %matches ;

foreach my $ext (@extensions) {
  my @nonmathing ;
  my @matching ;
  foreach my $file (@dlcopy) {
    if ($file =~ /\.$ext$/) {
      push @matching,$file ;
    } else {
      push @nonmatching,$file ;
    }
  }
  @dlcopy = @nonmatching ;
  $matches{$ext} = \@matching ;

}