#!/usr/bin/perl

use strict;

my $dir = '.';
my %directories = ();
my $dirsRef = \%directories;

&find_size($dir, $dirsRef);

foreach my $key (sort keys %directories) {
   print "$key has $directories{$key} bytes in it\n";
}

sub find_size {
   my ($currentDir, $dirsRef) = @_;
   opendir DIR, $currentDir;
   my @files = grep !/^\.\.?$/, readdir DIR;
   for my $blah (@files) {
      if (-d $blah) {
         &find_size($blah, $dirsRef);
      } else {
         $dirsRef->{$currentDir} += (-s $blah);
      }
   }
}