Arrays allow storing and accessing a collection of related data elements under a common name in C. An array is declared with a data type, name, and size. Elements are accessed using an index in square brackets. One-dimensional arrays store elements in contiguous memory locations. Multi-dimensional arrays can represent matrices by using multiple indices to access elements. Arrays can be initialized during declaration by providing initial values inside curly braces.

1. ARRAYS IN C
PRESENTED BY:
Narra bhargavi
22AJ1A0562
CSE-A

2. INTRODUCTION
• We know the fundamental data types, namely
char, int, float, double and it’s variations.
• Although these types are very useful, the
variable of these types can store only one value
at a given time.
• Therefore, these data types can be used only to
handle limited amounts of data.
• In many applications we need handle large
volume of data for processing.
• To process such large amounts of data we need
a powerful data type.

3. DEFINITION OF ARRAY
• An array is a fixed–size sequenced collection of
elements of same data type
• In simplest form, an array can be used to
represent a list of numbers, a list of names.
• An array is a collection of similar data items,
that are stored under a common name.
• A value in an array is identified by index or
subscript enclosed in square bracket with array
name.

4. FEATURES OF ARRAYS
• An array is a derived data type. It is used to
represent a collection of elements of the same
data type.
• The elements can be accessed with base
address (index) and the subscript defined for
the position of the element.
• The elements in an array are stored in
contiguous memory location.
• It is easier to refer the array elements by simply
incrementing the value of the subscript.

5. TYPES OF ARRAYS
1. One dimensional array
2. Two dimensional array
3. Multidimensional array
ONE DIMENSIONAL ARRAY
The collection of data items can be
stored under a variable name using only
one subscript

6. ARRAY DECLARATION
The general form of array declaration is:
data_type array_variable-name[size];
• Data_type – specifies the type of element that
will be contained in the array , such as int, char
• size –indicates the maximum number of
elements that can be stored inside the array.

7. EXAMPLE
• For example we want to represent a set of five numbers,
say (10,20,30,40,50) by an array variable number, then we
may declare the variable number as follows
int number[5];
• and the computer reserves five storage locations as shown
below:
Number[0]
Number[1]
Number[2]
Number[3]
Number[4]

8. ARRAY INTIALIZATION
Syntax:
data_type array_variable-name[SIZE]={LIST OF VALUE}
EXAMPLE :
int number[5]={10,20,30,40,50};
Number[0]
Number[1]
Number[2]
Number[3]
Number[4]
fv
10
20
30
40
50

9. MORE EXAMPLES FOR ARRAY INITIALIZATION
int counter[ ]= {10,20,30,40,50};
char name[ ]= { ’J’ , ’H’ , ’O’ , ’N’ , ’0” };
alternatively,
char name[ ]= “john”; //array with string
int number[5]={10,20};
number[0]=10,number[1]=20,
number[2]=0,number[3]=0,number[4]=0
•we can also initialize an array with scanf() function.
for example,
int x[5];
printf(“enter the values:”);
scanf(“%d%d%d”,&x[0],&x[1],&x[2]);

10. EXAMPLE PROGRAM
#include<stdio.h>
#include<conio.h>
void main()
{
int a[5],sum=0,i;
printf(“Enter 5 numbers”);
for(i=0;i<5;i++)
{
scanf(“%dn”,&a[i]);
sum=sum+a[i];
}
printf(“the sum of given numbers is : %dn”, sum);
}

11. TWO DIMENSIONAL ARRAY
SYNTAX:
data_type array_name [row-size][column-size];
INITIAZING TWO DIMENSIONAL ARRAY:
Like one dimensional arrays, two dimensional arrays can be
initialized by their declaration
int table[2][3] = {0,0,0,1,1,1};
will assigns the values as follows,
table[0][1]=0, table[0][1]=0, table[0][2]=0,
table[1][0]=1, table[1][1]=1, table[1][2]=1
the above statement can be written as
int table[2][3]={{0,0,0},{1,1,1}};
also
int table[2][3] = {
{0,0,0},
{1,1,1}
};

12. Example program
#include <stdio.h>
main()
{
int m, n, i, j, first[10][10], second[10][10], sum[10][10];
printf("Enter the number of rows and columns of matrix ");
scanf("%d%d", &m, &n);
printf("Enter the elements of first matrixn");
for ( i = 0 ; i< m ; i++ )
for ( j = 0 ; j < n ; j++ )
scanf("%d", &first[i][j]);
printf("Enter the elements of second matrixn");
for ( i = 0 ; i < m ; i++ )
for ( j = 0 ; j < n ; j++ )
scanf("%d", &second[i][j]);

13. for ( i= 0 ; i < m ; i++ )
for ( j = 0 ; j< n ; j++ )
sum[i][j] = first[i][j] + second[i][j];
printf("Sum of entered matrices:-n");
for ( i= 0 ; i< m ; i++ )
{
for ( j = 0 ; j < n ; j++ )
printf("%dt", sum[i][j]);
printf("n");
}
return 0;
}

14. MULTI-DIMENSIONAL ARRAY
C allows arrays of more-dimensions called multi-
dimensional array.
The general form of a multi-dimensional array is:
Type array-name[s1][s2][s3]…..[sn]
Where ‘s’ is the size of the dimension
int survey[3][5][2];
float table[5][4][5][3];