> I am using Borland 3.0 DOS and windows XP
You should really upgrade your compiler
> void main()
Yeah right
Use int main
As endless posts / FAQs will tell you
> n = 2+5 - 4*3 / 10 %2 -6;
Its an integer expression, so everything truncates to 0
Say perhaps
n = 2.0+5.0 - 4.0*3 / 10 %2 -6.0;
