The problem is underspecified. Digital clocks may run from

(a) 1:00 to 12:59 (b) 01:00 to 12:59 (c) 0:00 to 23:59 (d) 00:00 to 23:59 (e-h) any of the above with seconds appended, :00 to :59.

I agree that not all of these are common, but I have seen some uncommon ones. For that matter, I've seen ones not on the above list -- the Toronto subway stations used to contain digital clocks that ran from 0:00 to 12:59 (pm), then from 1:00 (pm) to 11:59 (pm), while a computer that I used to use had the inverse anomaly -- its time of day command displayed times from 12:00:00 to 12:59:59 (am), then 01:00:00 to 23:59:59!

I get the following results for the 8 cases.

CASE AM+PM HOURS pals/hr TOTAL OVERALL TOTAL (a) yes 1-9 6 54

10-12 1 3 114

(b) yes 01-05 1 5

06-09 0 0 10-12 1 3 16

(c) no 0-9 6 60

10-15 1 6 16-19 0 0 20-23 1 4 70

(d) no 00-05 1 6

06-09 0 0 10-15 1 6 16-19 0 0 20-23 1 4 16

(e) yes 1-9 60 540

10-12 6 18 1116

(f) yes 01-05 6 30

06-09 0 0 10-12 6 18 96

(g) no 0-9 60 600

10-15 6 36 16-19 0 0 20-23 6 24 660

(h) no 00-05 6 36

06-09 0 0 10-15 6 36 16-19 0 0 20-23 6 24 96

--Mark Brader (msb@sq.com)

lib/DbaDatabase.php:134: Warning: dba_replace() [<a href='function.dba-replace'>function.dba-replace</a>]: You cannot perform a modification to a database without proper access