(1)    For example:

#!/usr/bin/perl
#   wordcount.pl
#
#   This program uses wc to count the numbers of
#   characters, words and lines of any user specified
#   file.
#
#   by Kwok-Bun Yue
#   September 13, 1999
#
use strict;
print "file to count words => ";
my $filename = <STDIN>;
chomp $filename;
my $countline = `wc $filename`;
chomp $countline;
$countline =~ s/^\s*//;
my ($nlines, $nwords, $nchars) = split /\s+/, $countline;

print "For file $filename:\n",
      "   number of characters => $nchars.\n",
      "   number of words => $nwords.\n",
      "   number of lines => $nlines.\n";
exit 0;

(2)    For example:

use strict;
my $var1 = ['This', 'is', 'an', 'example', 'of',
            ['an', 'array', 'of', {hash => 'yes', array => 'no'}, 0, 1],
            {why => 'me', so => ()}, [{}]];
print "total count of var1 => ", itemCount($var1) , "\n";

my $var2 = 'hi';
print "total count of var2 => ", itemCount($var2) , "\n";

my $var3 = ();
print "total count of var3 => ", itemCount($var3) , "\n";

sub itemCount {
   my($input) = shift;
   my $result = 0;  # current node.
   my $i = 0;

   if (ref $input) {
      if (ref $input eq "ARRAY") {
         for ($i=0; $i < scalar @$input; $i++) {
             $result+= itemCount($$input[$i]);
         }
       }
       elsif (ref $input eq "HASH") {
          my @keys = sort keys %$input;
          for ($i=0; $i < scalar @keys; $i++) {
              $result += itemCount($$input{$keys[$i]});
          }
      }
   }
   else {
      $result = 1;
   }
   return $result;
}