my %add = ( a => 1,
            b => 2,
            c => 3,
          );
for (1 .. 10) {
    $totals{$_} += $add{$_} for keys %add;
}
print Dumper(\%totals);

##</code><code>##

    while (my ($k, $v) = each %add) {
        $totals{$k} += $v;
    }