-typedef struct et_forest *et_forest_t;
-typedef struct et_forest_node *et_forest_node_t;
-
-extern et_forest_t et_forest_create PARAMS ((void));
-
-extern void et_forest_delete PARAMS ((et_forest_t));
-
-extern et_forest_node_t et_forest_add_node PARAMS ((et_forest_t, void *));
-extern int et_forest_add_edge PARAMS ((et_forest_t, et_forest_node_t,
- et_forest_node_t));
-extern void et_forest_remove_node PARAMS ((et_forest_t, et_forest_node_t));
-extern int et_forest_remove_edge PARAMS ((et_forest_t, et_forest_node_t,
- et_forest_node_t));
-extern et_forest_node_t et_forest_parent PARAMS ((et_forest_t, et_forest_node_t));
-extern et_forest_node_t et_forest_common_ancestor PARAMS ((et_forest_t,
- et_forest_node_t,
- et_forest_node_t));
-extern void * et_forest_node_value PARAMS ((et_forest_t, et_forest_node_t));
-extern int et_forest_enumerate_sons PARAMS ((et_forest_t, et_forest_node_t,
- et_forest_node_t *));
+/* The node representing the node in an et tree. */
+struct et_node
+{
+ void *data; /* The data represented by the node. */
+
+ int dfs_num_in, dfs_num_out; /* Number of the node in the dfs ordering. */
+
+ struct et_node *father; /* Father of the node. */
+ struct et_node *son; /* The first of the sons of the node. */
+ struct et_node *left;
+ struct et_node *right; /* The brothers of the node. */
+
+ struct et_occ *rightmost_occ; /* The rightmost occurrence. */
+ struct et_occ *parent_occ; /* The occurrence of the parent node. */
+};
+
+struct et_node *et_new_tree (void *data);
+void et_free_tree (struct et_node *);
+void et_free_tree_force (struct et_node *);
+void et_free_pools (void);
+void et_set_father (struct et_node *, struct et_node *);
+void et_split (struct et_node *);
+struct et_node *et_nca (struct et_node *, struct et_node *);
+bool et_below (struct et_node *, struct et_node *);