Array and pointers are powerful tools to represent
group of data
items
of same data type with a single name. How ev'r if we want to
represent
a group of data items of different data types with a single
name,
the array concept will not support. So 'C' language provides a
data
type named as STRUCTURES to do this task.Thus the structure is
used
to collect the different type data items.
The
structure will allocate the memory for the member,during
execution
time.The memory will allocate in separatly for each and
every
member or structure Variable.
Syn:-
+----
Defining:-
========
struct
tag-name
{
<data-type>
member-1;
<data-type>
member-2;
.
.
.
};
Ex:-
struct
emp
{
int
enos;
float
sal;
char
name[30];
};
After
Defined the structure, Directly we can not able to access the
member
of the structure.If you need to access the members, you should
create
one structure variable.
If
you need to access the member of the structure,by using that
variable
name follwed by one period operator(.)then the structure
member.
Declaring
the Structure variable:-
=================================
struct
<tag-name> var1,var2,....;
Access
the member:
-----------------
var-name.member-name;
Initialization:-
---------------
struct
<tag-name> var1={ values };
struct
emp e={12,13.90,"sisi-cmtes"};
typedef
=======
This
statement is used to define a alias for existing data type. We
can
define a new data type based on the behaviour of existing data
type.
Syn:
---
typedef
<data-type> alias;
Once
we defined the alias, then we can use the alias anywhere in the
program.
Typedefinition
structure:-
--------------------------
The
typedefinition structure is collection of different data types.
It is
just a creating for new data type.
Syn:-
------
typedef
struct
{
<data-type>
<data-type>
..
..
}structure-name;
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