Thread: Question about loops.

There is no difference. It's just a matter of style preference.

>What is the reason for that?
Assuming the compiler takes you literally and doesn't implement an optimization that even Dennis Ritchie's first compiler used, the first is better because it avoids a temporary for the intermediate value. In theory, it's possible for i++ to be implemented like this:

Code:

int save = i;
i = i + 1;
return save;

Whereas ++i can be implemented like this:

Code:

i = i + 1;
return i;

In reality, you probably won't see a compiler that fails to optimize both into the same machine code (for a standalone expression like the example). Miracle C might be one of those hypothetical bad compilers, but I don't know for sure because I avoid it like the plague.

Use whichever you find clearer, but keep in mind that if you move to C++ there will be more of a difference because those operators can be overloaded. In such a case, it's better to use the prefix increment for class objects and whichever you want for built-in types.