Well, there are at least two low-level ways of determining whether a given number is even or not:
1. if (num%2 == 0) { /* even */ } 2. if ((num&1) == 0) { /* even */ }I consider the second option to be far more elegant and meaningful, and that's the one I usually use. But it is not only a matter of taste; The actual performance may vary: usually the bitwise operations (such as the logial-and here) are far more efficient than a mod (or div) operation. Of course, you may argue that some compilers will be able to optimize it anyway, and I agree...but some won't.
Another point is that the second one might be a little harder to comprehend for less experienced programmers. On that I'd answer that it will probably only benefit everybody if these programmers take that short time to understand statements of this kind.
What do you think?
The given two snippets are correct only if num is either an unsigned int, or a negative number with a two's complement representation. - As some comments righfuly state.