Data Structures C Language Question

Using what is implemented in the "DoublyLinkedList.h" file provided below implement the following functions

a. DoublyLinkedList newDoublyLinkedList() which should allocate the memory for a new doubly linked list, initialize the variables, and return the address.

b. void freeDoublyLinkedList(DoublyLinkedList list) which should free the linked list (including any nodes currently in the list).

c. NodeDL *allocateNode(Element value) which should allocate memory for a new node, store value inside this node, and return the address of the node.

d. void append(DoublyLinkedList list, Element value) which should add a new node (which stores value) to the end of the list. Notice that often one would want to insert into the middle of a linked list, but for this project it suffices to only insert at the end of a linked list.

/************************************************************************

DoublyLinkedList.h

 Purpose: Define constants used in the project Struct definitions for a general Doubly Linked List. Define function prototypes used by general Doubly Linked Lists. ************************************************************************/ #include  #include  #include  #include  //#define constant values #define MAX_URL_LENGTH 50 #define TRUE 1 #define FALSE 0 //typedef for the Element struct which constains a c string to store a URL in the BrowserList typedef struct { char szURL[MAX_URL_LENGTH]; } Element; //Typedef for a node in the doubly linked list (has next and previous pointers). typedef struct NodeDL { Element element; struct NodeDL *pNext; struct NodeDL *pPrev; } NodeDL; //Typedef for a doubly linked list implementation. //Contains a pointer to the first node in the list and the last node in the list (pHead and pFoot respectively). typedef struct { NodeDL *pHead; NodeDL *pFoot; } DoublyLinkedListImp; typedef DoublyLinkedListImp *DoublyLinkedList; /*****Prototypes*******/ //Malloc a new DoublyLinkedListImp and return it's address. DoublyLinkedList newDoublyLinkedList(); //Free the DoublyLinkedList and any nodes that still exist in the list void freeDoublyLinkedList(DoublyLinkedList list); //Allocate a new node and store "value" as the Element in the node. Return the address of the node. NodeDL *allocateNode(Element value); //Create a node to store the given Element and add it to the end of the DoublyLinkedList. void append(DoublyLinkedList list, Element value);