please I want from you help to do this home wrok

i have one question on the above script, i don't know if it is a good idea to post here since it's his homework, but what exactly does

Code:

---

++

---

do? can't find it in my online manual.

Prefix Increment and Decrement Operators: http://msdn2.microsoft.com/en-us/library/ms861682.aspx
C Postfix Increment and Decrement Operators: http://msdn2.microsoft.com/en-us/library/ms861673.aspx

thanks, yet again exactly what i needed to read up on it..
you guys are the best