Variables

In C++, all Variables must be assigned a valid data type. The data types of C++ are the same as in C:

• bool
• char
• int
• short
• double
• float
• long
• struct
• class
• enum

Declaring vs Defining variables

In C++, there are 2 ways of introducing variables. The first way is called declaration of a variable. The second is called definition of a variable. The following code snippet shows the differences:

The following codes show how to declare a variable:

int i; //declaration of i as type int
string s; //declaration of s as type string
 

After declaring a variable, you must assign a value to it. There are two ways to assign a value:

int i = 2; //declare variable i and assign value 2 to it

Or:

int i; //declare data type;
i = 2; //then assign a value.

↓