bscodinglab

Array

In C programming, an array is a collection of elements of the same data type, stored in contiguous memory locations.Arrays is used to store multiple values in a single variable. The elements in an array can be accessed by their index or position within the array.Array Always Start with index number 0 . define the data type (like int) and the name of the array followed by ” square brackets [] “.

.Example of Array :-

int myArray[ ] = {1, 2, 3, 4, 5};

In C programming, there are several types of arrays, including one-dimensional arrays, multi-dimensional arrays, and arrays of pointers. Here are some examples of each type of array in tabular format:

The way of  array Declaration And Initialize :-

1.Declare array  :-  int a[5];

Initialize the value of Array by index .

a[ 0 ]=10;       a[ 1 ]=20;       a[ 2 ]=30;            a[ 3 ]=40;            a[ 4 ]=50;

2. array Declare and initializetion at one time :- int a[  ] = {5,10,15,20,25,30};
Type of array :- 

A. One – Dimentional Array.

B. Multi – Dimentional Array. 

1.  One-dimensional array :-

A one-dimensional array is a collection of elements of the same data type, arranged in a single row.
// Example of a one-dimensional array of integers.

#include <stdio.h>

int main()

{

      int n[5] = {101, 102, 103, 104, 105};

       for(int i=0; i<5; i++)

       {

            printf(“n[%d] = %d\n”, i, n[i]);

         }

     return 0;

  }

Output:-

n[0] = 101
n[1] = 102
n[2] = 103
n[3] = 104
n[4] = 105

Explain Output:-

In the Given example, we have declared a 1D array of integers n. The array contains five elements, and each element is initialized with a value like output give below.Hare we have print the value of array with using of for loop.

Index01234
Value101102103104105

 Multi-dimensional array :-
A multi-dimensional array is an array that contains one or more arrays as its elements. In C programming, a two-dimensional array is the most common type of multi-dimensional array.
// Example of a two-dimensional array of integers

#include <stdio.h>
int main()

{
int n[3][3] = {{01,02,03},{04,05,06},{07,08,09}};
for(int i=0; i<3; i++)

     {
for(int j=0; j<3; j++)

            {
printf(” %d \t”,n[i][j]);
}
printf(“\n”);
}
return 0;

}

Output :-

01    02    03
04    05    06
07    08    09

Array of pointers :-

An array of pointers is an array where each element is a pointer to another data type.In simple words, the array is capable of holding the addresses a variables. Think of it like this- the array[0] will hold the address of one integer variable, then the array[1] will hold the address of the other integer variable.

// Example of an array of pointers to integers.

Example with Array to array
#include <stdio.h>
int main() {
    int *pointer_array[5];
    int  array[] = {10, 20, 30, 40, 50};   
         /* Assigning addresses of integer array elements */
    pointer_array[0] = &array[0];
    pointer_array[1] = &array[1];
    pointer_array[2] = &array[2];
    pointer_array[3] = &array[3];
    pointer_array[4] = &array[4];
     
    for(int i=0; i<5; i++)
    {
        printf("%d\n", *pointer_array[i]);
    }
    
    return 0;
}
Output :-   10 20 30 40 50

Example With Array to variables

#include <stdio.h>

int main() {

    int *pointer_array[5];

    int a=5,b=10,c=15,d=20;   

          /* Assigning addresses of individual variables */

    pointer_array[0] = &a;

    pointer_array[1] = &b;

    pointer_array[2] = &c;

    pointer_array[3] = &d;

    for(int i=0; i<4; i++)
    {

        printf("%d\n", *pointer_array[i]);

    }

     return 0;

}

Output :-5  10  15  20

Index012       3
Value51015     20

 Note :-  that in the above Example we create pointer-array contains the memory addresses of the variables a, b, and c,d. when we print array value by pointer.