my @data
while (my $line = <TEMPFILE>) {
        my @elements = $line;
        push @data, \@elements;    # need to store as ref
    }

@data = sort { $$a[2] cmp $$b[2]  or  $$a[1] <=> $$b[1] } @data or die "can't sort";



foreach my $item (@data) {
    print TEMPFILE @$item;
    print TEMPFILE "\n";
}