realloc() to dynamically increase size of an already allocated array

Using realloc() Function to Dynamically Increase the Size of an Already Allocated Array in C Programming Language

In C programming language, the realloc() function can be used to dynamically increase the size of an already allocated array. Here's how to use realloc() function:

1. Declare a pointer variable to the array:

   int *arr;

2. Allocate memory to the array using malloc() or calloc() function:

   arr = (int *)malloc(sizeof(int) * n);

   where n is the initial size of the array.

3. Use the array as needed.

4. If you need to increase the size of the array, use realloc() function:

   arr = (int *)realloc(arr, sizeof(int) * (n + m));

   where m is the additional number of elements to be added to the array.

5. Use the expanded array as needed.

6. When finished using the array, free the memory using free() function:

   free(arr);

Note that realloc() function may move the allocated memory block to a new location, so it's important to update the pointer variable accordingly.

In conclusion, realloc() function in C programming language can be used to dynamically increase the size of an already allocated array, making it a useful tool for managing memory efficiently. Understanding the syntax and practical applications of this function can help programmers write more flexible and efficient code.