Re: Beginer problem: variable array size

[tmoran@acm.org]

> The professor probably has files of input numbers that will
> be fed to each submitted program. I'll bet one of them is
> very large, to test the input size limit even if the sort
> won't complete in a reasonable amount of time.
  I'd be very interested in seeing an answer to the OP problem that had no
limit on the number of inputs.  I'd even be interested in a version that
would run with a very large number, say 6E23, of inputs.  Would it use all
the machines on the internet to store input?  I fear even that wouldn't be
enough.  If you can't show such a program, then I'd like to know what in
fact are its limits, either as a constant like 8*3600 or 10_000_000
or by a formula like "System_RAM_In_Bytes/2" or some such thing.

> Furthermore, if you are going to have an arbitrary limit,
> you have to provide the extra code to handle the case of
> the limit being exceeded.
  Not for an introductory class.  And for a more advanced class,
I suspect a "raised Storage_Error" message, or taking a year to run,
wouldn't receive a very high grade.

> And further yet, why do you think you get to rewrite the
> given requirements just because they don't suit the style of
  The OP problem spec was incomplete.  Given that it followed a Hello
World program, I suspect it came early in a programming class and the prof
would be happy with a quadratic sort and would test it with a few tens at
most of inputs.  If it was my homework, I'd include a statement of that
assumption and why I made it.  If the assignment came up in an advanced
class after the prof had been describing a space probe crashing into the
sun, collecting a measurement every 50 nanoseconds for one half second,
then sorting and transmitting those 10 million measurements in the
remaining half second before meltdown, I would make different
assumptions, document them, and write the program a different way.

  It's bad to make foolishly limiting assumptions, but worse to
depend on undocumented assumptions.  Just the act of documenting
them may encourage a programmer to Think! and make better assumptions.