+ if ((n->left != NULL) && (n->right != NULL))
+ {
+ c_avl_node_t *r; /* replacement node */
+ if (BALANCE (n) > 0) /* left subtree is higher */
+ {
+ assert (n->left != NULL);
+ r = c_avl_node_prev (n);
+
+ }
+ else /* right subtree is higher */
+ {
+ assert (n->right != NULL);
+ r = c_avl_node_next (n);
+ }
+
+ assert ((r->left == NULL) || (r->right == NULL));
+
+ /* copy content */
+ n->key = r->key;
+ n->value = r->value;
+
+ n = r;
+ }
+
+ assert ((n->left == NULL) || (n->right == NULL));
+