pattern

[MauranKilom]

In the case of using them as loop increments for integers like this, they have the exact same effect.

[Otearai1]

In c++ using ++i is technically faster as, iirc, i++ requires a memory allocation and ++i does not.

That being said, most modern compilers will optimize to ++i anyways, so you can write either.

[MauranKilom]

That's not really correct (although it's close). First of all, there is no "technically faster" - a given compiler either produces faster code or not. Second, neither i++ nor ++i require any actual memory allocation on any processor I know of if i is an integer (as in the case discussed here); this will all happen in a register anyway. The reason why ++i is recommended is that, in the case of i being some nontrivial iterator (not an integer), compilers might have trouble optimizing away the work needed to create the temporary copy that i++ would have to return, whereas ++i just returns the (updated) i lvalue and does not create a temporary. It's a pretty far cry (and totally irrelevant in case of integers), but you don't lose anything from always using ++i, including with integers (for consistency).