#define NAME_LEN 20
#define PHONE_LEN 20

typedef struct bst_node
{ 
	//int value;

	char name[NAME_LEN];
	char phone[PHONE_LEN];

	struct bst_node* right;
	struct bst_node* left;
}bst_node;

bst_node* create_bst_node(char name[NAME_LEN], char phone[PHONE_LEN]);

bst_node* bst_minimum(bst_node* node);

bst_node* bst_maximum(bst_node* node);

void print_bst(bst_node node);

void bst_inorder_traversal(bst_node* HEAD);

void bst_preorder_traversal(bst_node* HEAD);

bst_node* bst_search(bst_node* HEAD, char target_name[NAME_LEN]);

bst_node* bst_insert(bst_node* HEAD, char name[NAME_LEN], char phone[PHONE_LEN]);

bst_node* bst_delete(bst_node* root, char target_name[NAME_LEN]);

void treeLevelTraversal(bst_node* node);

void printTree(bst_node* node, int depth);

void delete_bst(bst_node* root);