C++ Variable

 C++ Variable

A variable is a name of memory location. It is used to store data. Its value can be changed and it can be reused many times.

It is a way to represent memory location through symbol so that it can be easily identified.

Let's see the syntax to declare a variable:

type variable_list;   

The example of declaring variable is given below:

  int x;    

  float y;    

  char z;    

Here, x, y, z are variables and int, float, char are data types.

We can also provide values while declaring the variables as given below:

int x=5,b=10;  //declaring 2 variable of integer type    

float f=30.8;    

char c='A';    

Rules for defining variables:

A variable can have alphabets, digits and underscore.

A variable name can start with alphabet and underscore only. It can't start with digit.

No white space is allowed within variable name.

A variable name must not be any reserved word or keyword e.g. char, float etc.

Valid variable names:

  int a;    

  int _ab;    

  int a30;    

Invalid variable names:

  int 4;    

  int x y;    

  int double;