{
    my $counter = 0;
    sub inc_counter { $counter++ };    # $counter is visible here
    sub get_counter { $counter };      # and here
}

##</code><code>##

$/ = "\n";
my $line = <STDIN>;     # <> operator reads just one line

my $whole_file;
{
    local($/) = undef;
    $whole_file = <F>;  # <> operator reads in all of the data from filehandle F
}

$line = <STDIN>;        # reads just one line again, since $/ returns to "\n"

##</code><code>##

for (0 .. 100) {
  next unless $_ % 2;     # skip multiples of 2
  next unless $_ % 5;     # skip multiples of 5
  print "$_\n";
}