my %from_to_bytes;
my %col_headings;

while (<DATA>) {
    ( $from, $to, $hh, $mm, $bytes ) = /^(\S+) (\S+) (\d+):(\d+) (\d+)$/
      or ( warn "bad format on line $.: $_" ), next;
    $from_to_bytes{$from}{$to} += $bytes;
    $from_to_bytes{$from}{"~~TOTAL"} += $bytes;
    $from_to_bytes{"~~TOTAL"}{$to} += $bytes;
    $col_headings{$to} = undef;
}

##</code><code>##

print join("\t", '', sort keys %col_headings, 'Total'),"\n";
for my $from ( sort keys %from_to_bytes ) {
    print (( $from eq '~~TOTAL' ) ? 'Total' : $from );
    print "\t$from_to_bytes{$from}{$_}" for (sort keys %{$from_to_bytes{$from}});
}