What's the easiest way to work out the difference between two positive integers?

I just need to know the difference between two int variables a开发者_开发百科 and b.

I'm new to Objective-C.

int diff = a - b;

or if you need the absolute difference:

int abs_diff = abs(a - b);

and if there is any chance that your expression might overflow:

int abs_diff = max(a, b) - min(a, b);