Pointers and Dynamic Arrays

Display 10.1 Uses of the Assignment Operator with Pointer Variables
p1 = p2;
p1
p2
*p1 = *p2;
p1
p2
Pointer Variables Used with =
If p1 and p2 are pointer variables, then the statement
p1 = p2;
Pointers 409
changes the value of p1 so that it is the memory address (pointer) in p2. A common way to think
of this is that the assignment will change p1 so that it points to the same thing to which p2 is currently
pointing.
address, we have merely indicated the address with an arrow that points to the variable
with that address.
Since a pointer can be used to refer to a variable, your program can manipulate variables
even if the variables have no identifiers to name them. The operator new can be
used to create variables that have no identifiers to serve as their names. These nameless
variables are referred to via pointers. For example, the following creates a new variable
of type int and sets the pointer variable p1 equal to the address of this new variable
(that is, p1 points to this new, nameless variable):
p1 = new int;
Before: After:
Before:
8
9
8
9
This new, nameless variable can be referred to as *p1 (that is, as the variable pointed to
by p1). You can do anything with this nameless variable that you can do with any other
p1
p2
p1
p2
After:
8
9
9
9
new