Is C++ Array passed by reference or by pointer?

Question

In school, our lecturer taught us that the entire array was passed by reference when we pass it to a function,.

However, recently I read a book. It

Answer 1

The terminology used by your lecturer is confusing. However, in a function declaration such as

void funcA(int []);

the int[] is just another way of saying int*. So funcA can take any argument that is or can be converted to an int*.

Arrays can decay to pointers to the first element in the right context. This means, for example, that you can assign an array's name to a pointer like this:

int array[42];  // array is of type int[42]
int * arr = array; // array decays to int*

So, when you pass array to funcA,

funcA(array); // array decays to int*

funcA has a pointer to the first element of the array.

But it is also possible to pass arrays by reference. It just requires a different syntax. For example

void funcB(int (&arr)[42]);

So, in your example, you are passing a pointer to the first element of the array, due to the signature of your function funcA. If you called funcB(array), you would be passing a reference.