Introduction to Array in C Language

Array is a collection of values having same data type and size. Elements of array are internally stored in consecutive locations.

We can access individual elements of array by using index of array elements where index is an integer value starting from 0.

Types of Array in C Language

There are three types of array:

• One dimensional Array
• Two dimensional Array
• Multi dimensional Array

One dimensional Array in C Language

In one dimensional array, we use only one subscript to specify the size or refer any array element. Syntax for declaring an array is:

<Type> Array_name[N];

Type represents valid data type of C like int, float, char etc.

Array_name is the array name defined by the programmer.

[ ] are called subscript used to define  array size in them.

N  is the maximum number of values that can be stored in array.

Example

int ARR[4];

Here A is a one dimensional array which can store maximum 4 values in it. Elements of array are referred as ARR[0],ARR[1],ARR[2] and ARR[3].

#include<stdio.h>
int main()
{
int ARR[3];
ARR[0]=10;
ARR[1]=20;
ARR[2]=30;
printf("\n%d",ARR[0]);
printf("\n%d",ARR[1]);
printf("\n%d",ARR[2]);
return(0);
}

10
20
30

Initialization of  one dimensional Array in C

Syntax to initialize a one dimensional array is:

<Type> Array_name[N]={List_of_values};

N specifies the size of array. It is optional while initializing array. Compiler automatically provides size to array as per number of values within the braces if we don’t specify array size during initialization.

Example

int a[3]={15,25,35};  //Initialization of int type array

#include<stdio.h>
int main()
{
int i, arr[4]={10,20,30,40};
printf("\nArray is");
for(i=0;i<4;i++)
printf("\n%d",arr[i]);
return(0);
}

Array is
10
20
30
40

#include<stdio.h>
int main()
{
int arr[4];
int i;
printf("\nEnter array elements :=");
for(i=0;i<4;i++)
  scanf("%d",&arr[i]);
printf("\nArray elements are:=");
for(i=0;i<4;i++)
  printf("\n%d",arr[i]);
return(0);
}

Enter array elements :=3
4
5
6
Array elements are:=
3
4
5
6