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

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

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:

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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

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.

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C++ Modify Pointers

You can also change the pointer's value. But note that this will also change the value of the original variable:

Example

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