C program implementing realloc() functions.

In the example below, we will be using the realloc() function. The realloc() the function will provide the flexibility to the users for changing the size of memory which is previously allocated by the dynamic memory location.

Code:

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int *p, i , n1, n2;
    printf("Enter the number of elements that you want to enter in the array: ");
    scanf("%d", &n1);

    p = (int*) calloc(n1 * sizeof(int));

    printf("Addresses of previously allocated memory are: ");
    for(i = 0; i < n1; ++i)
         printf("%u\n",p + i);

    printf("\nEnter the new size of the array: ");
    scanf("%d", &n2);
    p = realloc(p, n2 * sizeof(int));

    printf("Addresses of all newly allocated memory are: ");
    for(i = 0; i < n2; ++i)
         printf("%u\n", p + i);
    return 0;
}

The above code will display its output as below.

Output: