#!/usr/local/bin/perl
		
		use warnings;
		use diagnostics;
		
		use strict;
		use Data::Dumper;
		
		my %data;
		my $data_file = '/users/oliversti/documents/development/perl/alpaca book/alpaca_files/ch04/coconet.dat';
		my $all = '** all machines combined **';
		
		open FH, "$data_file" or
			die "Couldn't open $data_file: $!\n";
		
		while (<FH>)
		{
			next if (/^#/);
			my ($source, $destination, $bytes) = split;
			$data{$source}{$destination} += $bytes;
			$data{$source}{$all} += $bytes;
		}
		
		close FH or
			die "Couldn't close $data_file: $!\n";
		
		sub traffic_combined
		{
			$data{$b}{$all} <=> $data{$a}{$all}
		}
		
		for my $source (sort traffic_combined keys %data)
		{	
			print "$source data transfer out: $data{$source}{$all}.\n";
			sub traffic_machine
			{
				$data{$source}{$b} <=> $data{$source}{$a}
			}
			
			for my $destination (sort traffic_machine keys %{$data{$source}})
			{
				next if ($destination eq $all);
				print "$source -> $destination: $data{$source}{$destination}.\n";
			}
		}
	

##</code><code>##

		for my $source (sort {$data{$b}{$all} <=> $data{$a}{$all}} keys %data)
		{	
			print "$source data transfer out: $data{$source}{$all}.\n";
		
			for my $destination (sort {$data{$source}{$b} <=> $data{$source}{$a}} keys %{$data{$source}})
			{
				next if ($destination eq $all);
				print "$source -> $destination: $data{$source}{$destination}.\n";
			}
		}