[Tutor] which way do I go?

[Danny Yoo]

On Wed, 15 Oct 2003, Alan Gauld wrote:

> > >>>sumdifference (3, 9)
> >
> > my result should be 30
> > this comes from adding the numbers 4+5+6+7+8=30
>
> Look at how to define functions.


Time for more contradictory suggestions.  *grin*

Simplifed problem: Can you write a program that sums the numbers from 0 to
9?  How about a program that sums the numbers from 0 to 3?

More generally: Can you write a function that accepts an input 'n' and
sums the numbers from 0 to n?

This problem should be simpler for you, since the left endpoint is always
at zero.  (It should also remind you of a problem you really should have
seen in algebra called "Gauss's sum".)

If you have a function that solves the simpler zero-based problem, you can
get the sum of an arbitrary interval in a very cute way.

Good luck to you.