// insert stores a string (s) in the sorted binary tree,

// specified by its root (tree).

// It returns 0 if string (s) has been successfully inserted

// (i.e. no duplicates)

// It returns 1 if the string has not been inserted (due to duplicates)

// Hint: you can use strcmp(..) to compare two NULL-terminated C strings

// type "man strcmp" to learn how to use it.

int

insert(tnode_t *tree, char *s)

{

// TODO: Your code here

}

// pre-order performs a preorder traversal of the sorted binary tree

// and store the sequence of strings visited along the way in

// the array argument (result) whose allocated size is result_max

// It returns the number of strings stored in the result array.

// (Our tester part7_harness.c will allocate an array whose size (result_max) is

// larger than the number of strings to be stored.)

// In preorder traversal, you print the value in node n first, and then

// visit n's left child, and then visit n's right child.

// For example, for the tree below, the preorder traversal result is "a" "d" "b" "e"

// "a"

// \

// "d"

// / \

// "b" "e"

//

// Note: you are free to write an auxilary function and use it here.

int

preorder(tnode_t *tree, char **result, int result_max)

{

// TODO: your code here

}

// inorder performs an inorder traversal of the sorted binary tree

// and store the sequence of strings visited along the way in

// the array argument (result) whose allocated size is result_max

// It returns the number of strings stored in the result array.

// (Our tester part7_harness.c will allocate an array whose size (result_max) is

// larger than the number of strings to be stored.)

// In inorder traversal, you visit node n's left child first, then print the value in node n, and then

// visit node n's right child.

// For example, for the tree below, the inorder traversal result is "a" "b" "d" "e"

// "a"

// \

// "d"

// / \

// "b" "e"

//

// Note: you are free to write an auxilary function and use it here.

int

inorder(tnode_t *tree, char **result, int max_result)

{

// TODO: your code here

}

// del_tree de-allocates all nodes in the tree

// you should do not de-allocate the strings stored inside each node

void

del_tree(tnode_t *tree)

{

// TODO: your code here

}

--------

typedef struct tnode {
int data; struct tnode* left; struct tnode* right;
	} tnode_t;