difference between pointer to an array and pointer to the first element of an array

Question

int (*arr)[5] means arr is a pointer-to-an-array of 5 integers. Now what exactly is this pointer?

Is it the same if I declare int arr

Answer 1

If you write int arr[5], you are creating an array of five int on the stack. This takes up size equal to the size of five ints.

If you write int (*arr)[5], you are creating a pointer to an array of five int on the stack. This takes up size equal to the size of a pointer.

If it is not clear from the above, the pointer has separate storage from the array, and can point at anything, but the array name cannot be assigned to point at something else.

See my answer here for more details.