Let's write a simple function to create a node. This function should:

• As an argument, take a number of type int, which will be stored in the node in the data field;
• Create a pointer to a dynamically allocated memory area (taking into account the size of the node);
• Check the success of memory allocation for the node;
• Put the required value (function argument) into the data field;
• The next pointer must be NULL, since the function creates only one node;
• The function must return a pointer to the memory area where value is stored.

The AddNewNode() function takes a pointer to a pointer, because it can change the value of the pointer to the first (head) node of the list, as well as the value that will be stored in the new node:

void AddNewNode(struct Node** head, int value) 
{
	...
}

If the list is empty (*head == NULL), we simply update the pointer to the head of the list (*head) to point to the new node (newNode), in which case newNode will become the first node (head node). In the case of a non-empty list, we use a loop to look for the last node.

The current node plays the role of a buffer node, with its help we can iterate through the list and find a node that points to nowhere (*next == NULL).

Note

The last node in the list will have a next pointer equal to NULL.

struct Node* current = *head;

while (current->next != NULL) 
{
           …
}

After all, you need to make the new node newNode the last node, which means current->next must be equal to newNode. Now newNode is the last node in the list.

As a task, you need to figure out and add a function for adding new nodes to existing nodes.