diff tree1/tree.c tree2/tree.c
3c3
<  *  (store integer data with an integer key)
---
>  *  (introduces typedef)
5a6
>  * Xia Zhou, July 2016
17c18
< struct treenode {
---
> typedef struct treenode {
21c22
< };
---
> } tree_t;
29c30
< struct treenode *
---
> tree_t *
32c33
<   struct treenode *node = malloc(sizeof(struct treenode));
---
>   tree_t *node = malloc(sizeof(tree_t));
53,54c54,55
< struct treenode *
< tree_insert(struct treenode *node, const int key, const int data)
---
> tree_t *
> tree_insert(tree_t *node, const int key, const int data)
80c81
< tree_find(struct treenode *node, const int key)
---
> tree_find(tree_t *node, const int key)
diff tree1/tree.h tree2/tree.h
3c3
<  *  (store integer data with an integer key)
---
>  *  (introduces typedef)
12c12
< struct treenode;  // opaque to users of the module
---
> typedef struct treenode tree_t;  // opaque to users of the module
19c19
< struct treenode *tree_new(const int key, int data);
---
> tree_t *tree_new(const int key, int data);
27c27
< struct treenode *tree_insert(struct treenode *root, const int key, const int data);
---
> tree_t *tree_insert(tree_t *root, const int key, const int data);
32c32
< int tree_find(struct treenode *root, const int key);
---
> int tree_find(tree_t *root, const int key);
diff tree1/treetest.c tree2/treetest.c
17c17
< struct treenode *root;
---
> tree_t *root;