Variables In C, variable is a data name given to a data value stored in the memory and can vary at the time of execution. Name of the variable should be meaningful and in C there are some rules are defined for naming variables and rules to declare C Variables is that alphabets, digits and underscore, begins with the alphabets or underscores (_) and digits (0-9) and keyword cannot be used as a keyword. Here eitworld.com provides the learning tutorial of C variable with examples.
- A variable is a data name given to a data value stored in the memory.
- The value of variable can vary at the time of execution.
- Name of the variable should be meaningful and in C there are some rules are defined for naming variables which are as follows:
Rules for naming Variable
- Variable name may contain letters, digits and underscore (_) character.
- The variable name can begin with the letters as well as with underscore (_) character.
- A variable name should not start with digit.
- A variable name cannot contain punctuation characters like (@,#,$,%,^,&,* etc)
- A variable name cannot be a keyword.
- The variable names may be a combination of uppercase and lowercase characters. For example name and naME are not the same.
Variable Declaration in C
- Declaration of a variable is necessary before using it into the program.
- A variable is declared using a data type and a meaningful variable name. The basic syntax of variable declaration is as follows:
- A variable can be of any data type like int, float, double and char etc.
- Here are some examples of variable declaration:
int a,b,c;/*More than one variable of same type can be declare in single statement.*/
- Variable can be initialized using the assignment operator ‘=’.
- Variable declaration and initialization can also done in same line.
- The basic syntax to initialize a variable is as follows:
- Some examples of declaring constant in C++ are given here:
- Here is an example of variable initialization:
Here is an example of using variable in C program:
int a;/*Variable declaration*/
printf("nvalue of a is:%d",a);
- The output of the above program is as follows: