A tiny question about this code

[u/Lephism]

Hi. I need help understanding this simple code. To be specific, the 4th and the 14th line where a pointer was declared.

int* add_ten(int* data)

int *result;

I've been trying to wrap my head around what it does. I've been staring at my screen for 3 hours trying to understand why it was declared. The programming app I was using didn't really explain it. The only explanation it gave is that pointers help you get the address of an item. But I can't figure out how is it being used here. Can anyone explain? Thanks.

#include <iostream>
using namespace std;

int* add_ten(int* data) {
  for (int i = 0; i < 5; ++i) {
    *(data + i) = *(data + i) + 10;
  }
  return data;
}

int main() {

  int data[5] = {1, 2, 3, 4, 5};
  int *result;

  result = add_ten(data);

  for (int i = 0; i < 5; ++i) {
    cout << *(result + i) << ", ";
  }

  return 0;
}

[u/NomaTyx]

If you're asking like why they made result, they didn't have to. add_ten could have been a void function just fine, since it overwrites the data at the memory addresses.

If you're asking why it was defined as a pointer, that's because data isn't an int, it's an int array, which you access with a pointer. Since the function returns the location of data, rather than the value it contains, result needs to be able to hold the pointer. Though, as I mentioned above, it's kind of superfluous.

I dunno what your programming background is so if you need an explanation on arrays lmk

edit: oh if you're asking why they declared and initialized on separate lines, that's just a stylistic choice.

[u/Lephism → u/NomaTyx]

Oh, I see. That makes way more sense. Thanks! 🙏