/**********************************************************
 * Filename:  linkedlist.h                                *
 * Author:    Sue Evans                                   *
 * Written:   5/1/08                                      *
 * Section:   201staff                                    *
 * Email:     bogar@cs.umbc.edu                           *
 *                                                        *
 * This file contains the structure definition of a node, *
 * and typedefs of the types NODE and NODEPTR.  It also   *
 * contains the function prototypes for the functions     *
 * defined in linkedlist.c, which are the linked list     *
 * implementation of a list abstract data type.           *
 **********************************************************/


/************ Step 1 ***************/

#define NAMESIZE 20

/* NODEPTR is defined as an alias for
 * "struct node *" so it can be used
 * within the structure before it is
 * completely defined. */
typedef struct node * NODEPTR;



/* The STUDENT node will store info *
 * about one student in a class.    */
typedef struct student
{
   char  firstName[NAMESIZE];
   char  lastName[NAMESIZE];
   int   grade;        
   int   id;
} STUDENT;


/* A NODE is a structure that allows us to build a linked
** list since it has both a data portion and a NODEPTR as
** its members.  The NODEPTR called next is known as the
** link.
*/
typedef struct node
{
    STUDENT data;
    NODEPTR next;    /* OR struct node *next; */
}NODE;


/**********************************************
* Function: CreateNode()                      *
* Input:    none                              *
* Output:   a pointer (of type NODEPTR) is    * 
*           returned that points to the       *
*           newly allocated NODE.             *
*                                             *
* CreateNode() mallocs the memory necessary   *
* to hold a NODE.  The members of the NODE's  *
* structure are initialized, and the beginning*
* address of that memory is returned.         *
*                                             *
* NOTE: Exits if there is insufficient memory.*                 
**********************************************/ 
NODEPTR CreateNode (void);


/***********************************************
* Function: SetData                            *
* Inputs:   a pointer to a newly-created node  *
*           a STUDENT structure which          *
*            contains the data to be placed    *
*            into that node                    *
* Output:   None                               *
*                                              *
* The data member of the node pointed to by    *
* temp  (temp->data) is populated with the     *
* values in the STUDENT structure called value *
* in the function (the new student's info)     *
***********************************************/ 
void SetData (NODEPTR temp, STUDENT value);


/**************************************************
* Function: Insert                                *
* Inputs:   the address of head which is of type  *
*            NODEPTR * and is called headPtr      *
*            within this function                 *
*           a pointer to the node to insert which *
*            is of type NODEPTR and is called     *
             temp within the function             *
* Output:   None                                  *
*                                                 *
* The node 'temp' is added to the linked list at  *
* the end of the list.                            *
**************************************************/ 
void Insert (NODEPTR* headPtr, NODEPTR temp);



/*************************************************
* Function: Delete                               *
* Inputs:   the address of the head (NODEPTR*)   *
*            called headPtr in the function      *
*           the id of student to be deleted (int)*
* Output: If found, the student id of the        *
*          student being deleted is returned     *
*         If not found, a -1 is returned         *
*                                                *
* The list is traversed looking for a NODE that  *
* has as the student's id the value passed in as *
* the target.  If the id number that matches the *
* target is found, the node is deleted from the  *
* list and the id number is returned.  If the end*
* of the list is reached without encountering the*
* target id number, then -1 is returned          *
*************************************************/ 
int Delete (NODEPTR* headPtr, int target);


/********************************************
* Function: IsEmpty                         *
* Input:    a pointer to the head of the    *
*            linked list                    *
* Output:   returns 1 (true) if the list is *
*            empty; returns 0 (false) if    *
*            the list is not empty          *
*********************************************/
int IsEmpty (NODEPTR head);


/*************************************************
* Function: PrintList                            *
* Input:    the head of the list                 *
* Ouput:    None                                 *
*                                                *
* Each data in each node in the list is printed  *
* according to the format specified              *
*************************************************/ 
void PrintList (NODEPTR head);



/** !!! Don't forget to finish guarding this header file!!! **/