On Fri, 27 Oct 2006, Ruby Quiz wrote:

> 	The Challenge
> 	---------------------------------------------------------------------
>
> Requirement #1: Write a Ruby program that shows the current time, but only the
> 'tens' part of the minutes. For example, if the time is 10:37, then the program
> might output "10:3~"
>
> Requirement #2: The time shown by the clock must randomly vary +/- 5 minutes
> from reality. For example, if the time is actually 10:37, the program might
> output "10:3~" or "10:4~" (but not "10:2~" or "10:5~").
>
> Requirement #3: The time on the clock should continuously increase. If the time
> shows "10:4~" it must continue to show "10:4~" until it shows "10:5~". (It can't
> show "10:4~", then "10:3~" for a bit and then come back to "10:4~".)


it seems like #2 and #3 contradict one another.  imagine it's 10:45 and,
through randomness, you choose to vary the clock by +5, therefore displaying
10:5~, you will not be able to change the output again until 10:55, and then
only because the upper bould will have rolled over into the next hour. here it
is in table form

   -----    ------    -----    ---------
   lower    actual    upper    selection
   -----    ------    -----    ---------
   10:40    10:45     10:50    10:50/5~
   10:41    10:46     10:51    10:51/5~
   10:42    10:47     10:52    10:52/5~
   10:43    10:48     10:53    10:53/5~
   10:44    10:49     10:54    10:54/5~
   10:45    10:50     10:55    10:55/5~
   10:46    10:51     10:56    10:56/5~
   10:47    10:52     10:57    10:57/5~
   10:48    10:53     10:58    10:58/5~
   10:49    10:54     10:59    10:59/5~
   10:50    10:55     11:00    11:00/0~

an initial high selection eats into subsequent ranges - in otherwords a
selection of t+ means that #2 will not by able to hold: the variance will be
required to b smaller for the next choice:  a high selection eats the variance
range of the next choice...

it's possibly even worse when we not near the top of an hour and start of with
maximum variance:

   -----    ------    -----    ---------
   lower    actual    upper    selection
   -----    ------    -----    ---------
   10:20    10:25     10:30    10:30/3~
   10:21    10:26     10:31    10:31/3~
   10:22    10:27     10:32    10:32/3~
   10:23    10:28     10:33    10:33/3~
   10:24    10:29     10:34    10:34/3~
   10:25    10:30     10:35    10:35/3~
   10:26    10:31     10:36    10:36/3~
   10:27    10:32     10:37    10:37/3~
   10:28    10:33     10:38    10:38/3~
   10:29    10:34     10:39    10:39/3~
   10:30    10:35     10:40    10:30/3~
   10:31    10:36     10:41    10:31/3~
   10:32    10:37     10:42    10:32/3~
   10:33    10:38     10:43    10:33/3~
   10:34    10:39     10:44    10:34/3~
   10:35    10:40     10:45    10:35/3~
   10:36    10:41     10:46    10:36/3~
   10:37    10:42     10:47    10:37/3~
   10:38    10:43     10:48    10:38/3~
   10:39    10:44     10:49    10:39/3~
   10:40    10:45     10:50    10:50/5~

so the combined effect means that it's acceptable to display the same time~
for twenty straight minutes - is that really the a desired potential effect?



-a
-- 
my religion is very simple.  my religion is kindness. -- the dalai lama