int** a = new int*[n](); What does this function do?

Question

int** a = new int*[n]();

I can't find any explanation for this code, all I find is explanations for code like int *array = new int[n];. I understand it but I can't completely figure out the code above. What does it mean?

Answer 1

create a pointer to an array of size n, where every entry is a pointer to integer

You'll get an array of pointers

Answer 2

As you (should) know, int *a = new int[n]; allocates an array of ints with size n.

So, in general, T * a = new T[n]; allocates an array of Ts with size n.

Now if you substitute T = int *, you'll get int **a = new int*[n];, which allocates an array of int *s (that is, of pointers to int).

Adding () on the right zeroes every pointer in the array (otherwise they would be uninitialized).