Enumeration or enum in C Programming

Enumeration or enum in C Programming

• ·         An Enumeration is user defined data type. It uses the keyword enum.
• ·    An enumerated type has a finite number of named values. Each named values assigned to integer constant in ascending order.
• ·         The symbolically declared members are known as “enumeration constants”.
• ·         The enumeration statement should starts with the keyword enum.

            Syntax    :       enum Tag

{

Member1, Member2, - - - - - , Membern

};

            Each enumeration member is assigned with an integer value by the compiler.  By default, Member1 is given the value 0, Member2 is given the value 1 and so on.  i.e., each member value is obtained by adding 1 to the previous member value.

           

Example C program

#include <stdio.h>

enum week

{

Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday

} ;

void main()

{

printf("\nSunday = %d ", Sunday);

printf("\nWednesday = %d ", wednesday);

printf("\nSaturday = %d ", Saturday);

}

Output

Sunday : 0

Wednesday : 3

Saturday : 6

Note:

                Enumeration provides a convenient way to associate constant values with names as alternative to #define statements.

            Example:         #define TRUE 1

                                    #define FALSE 0

            An alternative representation with enumeration data type is :

            Example:         enum flag

{

FALSE, TRUE

};

ANONYMOUS ENUMERATION

The process of specifying an enumeration without tag is known as anonymous enumeration.  The general format of defining anonymous enumeration is:

Syntax             :           enum

                                    {

                                                Member1, Member2, - - - - - - , Membern

                                    };