/* File: list1a.h
  
   Interface for an array implementation of 
   the list ADT used in list1.h
*/

#ifndef list1a_h
#define list1a_h


/* Type Definitions */  

/* In the array implementation, each node is just a string */
typedef char *node ;

typedef struct {
   node   *array ;
   int    size ;
   int    limit ; 
} *list ;


/* Function Prototypes */


/* Make a new list */
list CreateList(void) ;


/* Add item to the end of the list */
void Append(list L, char *item) ;


/* Add item to the beginning of the list */
void Prepend(list L, char *item) ;


/* Does item with key appear on the list? 0=No 1=Yes */
int IsMember(list L, char *key) ;


/* Returns the pointer to the node that contains the given key, or
   NULL if no such node.

   Note: that this is different from the representation used in
   the linked list implementation, but the main program doesn't
   need to know this.
*/
node *Locate(list L, char *key); 


/* Remove item in given position from the list.
   See note regarding position in documentation for Locate().
*/
void Delete(list L, node *position) ;


/* Add list L2 to the end of list L1.  L2 is destroyed.  */
void Concatenate(list L1, list L2) ;


/* Duplicate of the list. All items and nodes have newly allocated memory.
*/
list ListDup(list L) ;


/* Print the contents of the list. */
void PrintList(list L) ;


/* Free memory allocated to the list. */
void FreeList(list L) ;


/* String in first item returned, or NULL if list is empty */
char *FirstItem(list L) ;


/* String in last item returned, or NULL if list is empty */
char *LastItem(list L) ;


/* Returns number of items in the list */
int CountList(list L) ;


#endif