C++ Dereference
Get Memory Address and Value
In the example from the previous page, we used the pointer variable to get the memory address of a variable
(used together with the & reference operator). However, you can also
use the pointer to get the value of the variable, by using the * operator
(the dereference operator):
Example
string food = "Pizza"; // Variable declaration
string* ptr = &food; // Pointer declaration
// Reference: Output the memory address of food with the pointer (0x6dfed4)
cout << ptr << "\n";
// Dereference: Output the value of food with the pointer (Pizza)
cout << *ptr << "\n";
Try it Yourself »
string* ptr = &food; // Pointer declaration
// Reference: Output the memory address of food with the pointer (0x6dfed4)
cout << ptr << "\n";
// Dereference: Output the value of food with the pointer (Pizza)
cout << *ptr << "\n";
Note that the * sign can be confusing here, as it does two different things
in our code:
- When used in declaration (string* ptr), it creates a pointer variable.
- When not used in declaration, it act as a dereference operator.