Binary Search Tree linked list header file C Language

/* 17-8-09-11-21.20.h -- Chapter 8 Question */<br/> # ifndef last_h _ <br/> # define add_an_item 1 <br/> # define size 20 </P> <p>/* define the data type */<br/>/* name_and_pet data type exposed to the user */<br/> typedef struct name_and_pet <br />{< br/> char petname [size]; /* pet name */<br/> char petkind [size];/* pet type */<br/>} name_and_kind; <br/> typedef struct item <br/> {<br/> name_and_kind; <br/> struct item * Next; <br/>} item; <br/> typedef struct node <br/> {<br/> item * item; <br/> struct node * left; <br/> struct node * right; <br/>} node; <br/> typedef node * tree; </P> <p>/* interface function declaration */</P> <p>/* operation: before initializing a tree as an empty tree */<br/>/*: Point ptree to a tree */<br/>: the tree is initialized as an empty tree */<br/> void inatializetree (TREE * const ptree); </P> <p>/* operation: determine whether the tree is empty */<br/>/* before the operation: ptree points to a tree */<br/>/* after the operation: if the tree is empty, return 1; otherwise, 0 */<br/> int treeisempty (const tree * const ptree) is returned. </P> <p>/* operation: before adding a project to the tree */<br/>/*: pitem points to the data to be added, ptree points to an initialized binary search tree */<br/>/*: if possible, point data to pitem and add it to the tree. A node may be added, it may also be added to the next pointer of the node, and 1 is returned; otherwise, 0 */<br/> int insert (TREE * const ptree, const name_and_kind * const p_name_and_pet) is returned ); </P> <p>/* operation: returns the pointer to the leftmost node in the tree */<br/>/* before the operation: ptree points to an initialized binary search tree */<br/>/* after the operation: returns the pointer to the leftmost node in the tree */<br/> node * findmin (const tree * const ptree); </P> <p>/* operation: returns the pointer to the rightmost node in the tree */<br/>/* before the operation: ptree points to an initialized binary search tree */<br/>/* after the operation: returns the pointer to the rightmost node in the tree */<br/> node * findmax (const tree * const ptree); </P> <p>/* operation: delete a node or item data with the specified name_and_kind type from the tree */<br/>/* before the operation: ptree points to an initialized Binary Search Tree, p_name_and_kind points to data of the item type */<br/>/*: if possible, delete a node with p_name_and_kind pointing to data from the tree or a name_and_kind type data pointed to by the node pointer, and return the new tree; otherwise, the original tree */<br/> tree Delete (TREE * const ptree, name_and_kind * p_name_and_kind) is returned. </P> <p>/* operation: returns a pointer to a node with the specified name_and_kind.petname type data. */<br/>/* before the operation, the tree is an initialized Binary Search Tree, p_name_and_kind is a pointer to name_and_kind type data */<br/>/*: if possible, return a pointer to this node; otherwise, null */<br/> node * seekandreturn (const TREE tree, const name_and_kind * const p_name_and_kind) is returned. </P> <p>/* operation: before accessing each project in the tree in a central order */<br/>/*: ptree points to an initialized Binary Search Tree, and pfun points to a non-return value, after receiving a function */<br/>/* that points to the item pointer type value as a parameter: the function pointed to by pfun applies to each node in the tree in a forward Order */<br/> void inordertraversal (const tree * const ptree, void (* pfun) (const item * const pitem); </P> <p>/* operation: before deleting all nodes in the tree */<br/>/* operation: ptree points to an initialized binary search tree */<br/>/* after the operation: all nodes in the tree are deleted */<br/> // void deleteall (TREE * const ptree); </P> <p> # endif