C++ Pointers
Creating Pointers
You learned from the previous chapter, that we can get the memory
address of a variable by using the &
operator:
Example
string food = "Pizza";
// A food variable of type string
cout <<
food; // Outputs the value of food (Pizza)
cout << &food; // Outputs the memory address of food (0x6dfed4)
Try it Yourself »
A pointer however, is a variable that stores the memory address as its value.
A pointer variable points to a data type (like int or string) of the same
type, and is created with the * operator. The address of the variable you're working with is assigned to the pointer:
Example
string food = "Pizza"; // A food variable
of type string
string* ptr =
&food; // A pointer variable, with the name
ptr, that stores the
address of food
// Output the value of food (Pizza)
cout << food << "\n";
// Output
the memory address of food (0x6dfed4)
cout << &food << "\n";
//
Output the memory address of food with the pointer (0x6dfed4)
cout <<
ptr << "\n";
Try it Yourself »
Example explained
Create a pointer variable with the name ptr, that points to a string variable, by using the
asterisk sign
* (string* ptr).
Note that the type of the pointer has to match the type of the variable you're
working with.
Use the & operator to store the memory address of the
variable called food, and assign it to the pointer.
Now, ptr holds the value of food's memory address.
Tip: There are three ways to declare pointer variables, but the first way is preferred:
string* mystring; // Preferred
string *mystring;
string * mystring;
