While reading a downloaded Perl module, I found several ways of defining input parameters, which are listed as following. What are the differences between them?

```
sub new{
  my $class = shift;
  my $self = {@_};
  bless{$self,  $class};
}

sub count1{
  my ($self, $lab1) = @_;
}

sub new1{
  my ($class, $lab1) = @_;
  my $self = {};
  bless $class, $self;
}

sub setpath{
  my $self = shift;
}

```