Proper usage of realloc()

Just don’t call free() on your original ptr in the happy path. Essentially realloc() has done that for you.

ptr = malloc(sizeof(int));
ptr1 = realloc(ptr, count * sizeof(int));
if (ptr1 == NULL) // reallocated pointer ptr1
{       
    printf("\nExiting!!");
    free(ptr);
    exit(0);
}
else
{
    ptr = ptr1;           // the reallocation succeeded, we can overwrite our original pointer now
}