sub mysub { 
    my @array = @$_[0];    # Makes a copy. Not efficient.
    print $array[0], "\n";
}

my @a = (1 .. 10);
 
mysub(\@a);    # \@a is a reference to the array @a.

##</code><code>##

mysub { 
    my @array = @_;    # Copying again. Not efficient.
    print $array[0], "\n";
}
my @a = (1 .. 10); 

mysub(@a);    # Send the array as @_ 

##</code><code>##

mysub {
    my ($arrayref) = @_;
    print $arrayref->[0], "\n";
}
my @a = (1 .. 10); 

mysub( \@a );