When we need to point to another pointer in cpp ?

Answer 1

You would use it if you want to reference an array of dynamically allocated arrays or objects.

Similar to as pointed out by AKC, a

double** array2D = new double[] { rowA, rowB, .. };

Can be used to access an array of pointer, each of these which points to an array of doubles.

Or you can have an array of objects

MyType** arrayOfObjs = new MyType[] { new MyType(), new MyType() };

(Be careful to delete these appropriately!)

However, when working with objects, it is more common to use a vector of dynamically allocated objects instead of a '**'.

Answer 2

Use pointers-to-pointers like char** a so a stores a pointer to the memory where an adress (pointer) of a char is stored

Answer 3

i mean what is the purpose

Answer 4

pointer to a C array?

Answer 5

since c++ is mainly used for hardwares it deals with the limited amount of memory a hardware have. say for example you just created x=15, and the next line you add some value, this cause the program to make 2 memory allocation for the same variable,. if you use pointers it changes the value of x directly which means you will not create a duplicate variable in the memory thus saving more space in your hardwares' memory for further usage