#!/usr/local/bin/perl -w
use strict;
$|++;

# array of non-unique words
my @non_unique = ('bob and sue', 'bobcat', 'carpet', 'bob', 'car', 'carpet');

# create empty pseudo-hash
#   hash key is unique word, hash value is array index, array value is count
my $ph = [{},]; 

for(@non_unique) 
{
	if(exists $ph->{$_})     # if word already in hash,
	{
		$ph->{$_}++;         #   increment word count
	}
	else                     # else
	{
		$ph->[0]{$_} = @$ph; #   set hash key to last array index (end of array)
		$ph->{$_}++;         #   increment word count to 1
# 		or in one line... (a little obfuscated)
# 		$ph->[$ph->[0]{$_} = @$ph]++;
	}
# 	or on one line... (a little more obfuscated - not recommended)
# 	exists $ph->{$_} ? $ph->{$_}++ : $ph->[$ph->[0]{$_} = @$ph]++;
}
# or on one line... (even more obfuscated - really not recommended)
# map{exists$ph->{$_}?$ph->{$_}++:$ph->[$ph->[0]{$_}=@$ph]++}@non_unique;

# array of unique words, same order as non-unique words
#   (the extraction procedure looks a little messy)
#   it says, for the keys of the hash section of the pseudo-hash,
#     sort by the value, ascending
my @unique = sort { $ph->[0]{$a} <=> $ph->[0]{$b} } keys %{$ph->[0]};

# pretty formatted output of unique array and word count
format SortedWordsAndCountHeader =
Words               Count
.
format SortedWordsAndCount =
@<<<<<<<<<<<<<<<<<< @>>>>
$_,                 $ph->{$_}
.

$^ = "SortedWordsAndCountHeader";
$~ = "SortedWordsAndCount";
write for @unique;