Variables in C/C++

Variable:

Variable is nothing itself. It is actually name of memory location that our program can manipulate. In C language every variable specified by type which determine the size and layout of variable. These are called data types. such as:

char

int

float

double

void

Variable Declaration:

Variable declaration means defining variable in C language. We define variable declaration by using data type and variable name.

Syntax:

datatype variable name;

Example:

int num;

char name;

float salary;

Variable Initialization:

Variable initialization mean assigning value to variable. The syntax of variable initialization is given below:

Syntax:

datatype   variable name   value;

Example:

int num=1;

char name=a;

float num=2;

Rules for Naming Variable:

• First letter of variable name is must be alphabet
• The length of variable name is 39.
• Underscore is used in variable name.
• C is case sensitive language i.e. Upper and Lower case means variable names NUMBER and variable name number both are different variables.
• Spaces are not alllowed in variable name.