C++ Variables

C++ Variables

Variables are containers for storing data values.

In C++, there are different types of variables (defined with different keywords), for example:

• int - stores integers (whole numbers), without decimals, such as 123 or -123
• double - stores floating point numbers, with decimals, such as 19.99 or -19.99
• char - stores single characters, such as 'a' or 'B'. Char values are surrounded by single quotes
• string - stores text, such as "Hello World". String values are surrounded by double quotes
• bool - stores values with two states: true or false

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Declaring (Creating) Variables

To create a variable, you must specify the type and assign it a value:

Syntax

Where type is one of C++ types (such as int), and variable is the name of the variable (such as x or myName). The equal sign is used to assign values to the variable.

To create a variable that should store a number, look at the following example:

Example

Create a variable called myNum of type int and assign it the value 15:

You can also declare a variable without assigning the value, and assign the value later:

Example

Note that if you assign a new value to an existing variable, it will overwrite the previous value:
 

Example

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Other Types

A demonstration of other data types:

Example

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Display Variables

The cout object is used together with the << operator to display variables.

To combine both text and a variable, separate them with the << operator:

Example

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Add Variables Together

To add a variable to another variable, you can use the + operator:

Example

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