1 2 3 4 5 012345678901234567890123456789012345678901234567890 #### 11 12 13 14 15 ...478901234567890123456789012345678901234567890 #### sub ruler { my($n,$r) = ($_[0], ' '); $r .= ' 'x(10-length).$_ for (1..($n+9)/10); return "$r\n" . '0123456789' x (($n+9)/10) . "0\n"; }