<pre>
The problem is underspecified.  Digital clocks may run from

<pre>
	(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.
</pre>

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.

<pre>
	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
</pre>

--Mark Brader (msb@sq.com)
</pre>
