Source Code : Array And Structure In C

Arrays

•Arrays fall under aggregate data type

•Aggregate – More than 1

•Arrays are collection of data that belong to same data type

•Arrays are collection of homogeneous data

•Array elements can be accessed by its position in the array called as index

•Array index starts with zero

•The last index in an array is num – 1 where num is the no of elements in a array

•int a[5] is an array that stores 5 integers

•a[0] is the first element where as a[4] is the fifth element

•We can also have arrays with more than one dimension

•float a[5][5] is a two dimensional array. It can store 5x5 = 25 floating point numbers

•The bounds are a[0][0] to a[4][4]

•Structures are user defined data types

•It is a collection of heterogeneous data

•It can have integer, float, double or character data in it

•We can also have array of structures

Structure

struct <>

{

  members;

}element;

We can access element.members;

struct Person

{

int id;

char name[5];

}P1;

P1.id = 1;

P1.name = “vasu�;

Type def

•The typedef operator is used for creating alias of a data type

•For example I have this statement

typedefint integer;

Now I can use integer in place of int

i.e instead of declaring int a;, I can use

integer a;

This is applied for structures too.