#!/usr/bin/perl

use strict;  #  Yeah, I don't normally do this, but ya wanted readable...

#  Open the input file
my $fileName = shift @ARGV;
open INPUT, $fileName or die "Cannot find $fileName\n";

my %wordCount;  #  The hash to hold the words.

#  Loop over ieach line in the input
while (<INPUT>)
{
   #  And over each word in the line
        #while (/\b(\w+)\b/g) # This is my definition of word, which doesn't
                              # match yours.  I like mine lots better, but
                                                                 # it's your game, so...
        while (/(\S+)\s+/g)
        {
           $wordCount{lc $1}++ ;
        }
}

# Build the results
my (@result, $key, $value); #  Declaring variables first, like I should
while ( ($key, $value) = each %wordCount)
{
  push @result, "$value\t$key\n"
}

# sort the results
# hey, this is a scripting language
# I care more about programmer efficiency than program efficiency, so
# I'm using the built in sort, customizing the compare
@result = sort { ($b <=> $a) || ($a cmp $b) } @result;
print @result;