Thanks for the PR! The change from pre-increment/decrement to post-increment/decrement looks correct and fixes the off‑by‑one behavior:

* In `push`, `stack[stack_pointer++] = element;` is the right choice if `stack_pointer` tracks the next free slot.

* In `pop`, `return stack[--stack_pointer];` correctly moves back to the last pushed element before reading.

A couple of suggestions to strengthen this and future contributions:

* Add brief comments documenting the stack invariant: “`stack_pointer` points to the next free slot.”

* Include small tests (or a demo `main`) for: push/pop single item, push until full, pop until empty, and verify strict LIFO.

* Consider returning a status from `push`/`pop` (e.g., int/bool with out‑param) instead of printing errors; returning `0` from `pop` is ambiguous if `0.0` is a valid value.

* Use `size_t` for `stack_pointer` and comparisons with `STACK_SIZE`.

* Optionally guard against overflow/underflow with asserts in debug builds.

Overall, nice, focused fix with clear correctness improvement. If you’re up for it, similar sanity checks and invariants across other stack/queue exercises would be super valuable.

Thank you for the suggestions, I would be happy to contribute more (if my time allows)!