Unions in c S-Teacher

1. UNION

2. UNION
Union has members of different data types, but can
hold data of only one member at a time.
The different members share the same memory
location.
The total memory allocated to the union is equal to
the maximum size of the member.

3. EXAMPLE
#include <stdio.h>
union marks
{
float percent;
char grade;
};
int main ( )
{
union marks student1;
student1.percent = 98.5;
printf( "Marks are %f address is %16lun", student1.perc
ent, &student1.percent);
student1.grade = 'A';
printf( "Grade is %c address is %16lun", student1.grade,
&student1.grade);
}

4. ENUM

5. ENUMERATED DATATYPE
Enumeration is a user-defined data type. It is
defined using the keyword enum and the syntax
is:
enum tag_name {name_0, …, name_n} ;
The tag_name is not used directly. The names in
the braces are symbolic constants that take on
integer values from zero through n.

6. Enumerated(contd.)
As an example, the statement:
enum colors { red, yellow, green } ;
creates three constants.
red is assigned the value 0,
yellow is assigned 1 and
green is assigned 2.