How to store Pointer's memory location?

Question

Pointers store memory location of other variables.
How to store the memory location of pointer1 in pointer2

Answer 1

you can use a pointer to a pointer; example:

int x=0;
int *ptr1 = &x;
int **ptr2 = &ptr1;

in this case ptr2 store the address of ptr1.
You can also change the value of x by dereferencing twice ptr2:

main()
{
using namespace std;
int x=0;
int *ptr1 = &x;
int **ptr2 = &ptr1;

**ptr2 = 3;
cout << "value of x is: " << x;
return 0;
}

this will print 3 as the value of x, because you changed it using ptr2

Answer 2

@pleurobot What does * and ** indicate in variable declaration