Function summing n integers

[foncused]

Having trouble writing a function "compute_sum" that will ask for n input and then sum the first n integers (If 5 is entered, 5+4+3+2+1). I assume the function will need to include a loop, but do not know which to use, for, do while or just while.

[firedraco]

I would actually use a for loop, but you could use a while loop (since for loops can be changed to while loops and vice versa).

http://www.cplusplus.com/doc/tutorial/control/#loops

[foncused]

Thanks, I was considering the For loop, but cant seem to figure out the code that will sum the numbers:

Its basically n + (n-1) + (n-2)....etc. until n=0

[jsmith]

for( int i = 1; i <= N; ++i )

counts from 1 to N.

You figure out the rest.

or, the sum of the first N integers is N * ( N + 1 ) / 2.

[foncused]

Fair enough, I will spend some more time on it and figure out the rest on my own. Thanks firedraco and jsmith!