1 files changed, 45 insertions, 0 deletions

diff --git a/treeutil.h b/treeutil.h
new file mode 100644
index 0000000..302a6e3
--- /dev/null
+++ b/treeutil.h
@@ -0,0 +1,45 @@
+// aux display and verification routines, helpful but not essential
+struct trunk {
+        struct trunk *prev;
+        char * str;
+};
+ 
+static void show_trunks(struct trunk *p)
+{
+        if (!p) return;
+        show_trunks(p->prev);
+        printf("%s", p->str);
+}
+ 
+// this is very haphazzard
+static void show_tree(struct tree_node *root, struct trunk *prev, int is_left)
+{
+        if (root == NULL) return;
+
+        struct trunk this_disp = { prev, "    " };
+        char *prev_str = this_disp.str;
+        show_tree(root->right, &this_disp, 1);
+
+        if (!prev)
+                this_disp.str = "---";
+        else if (is_left) {
+                this_disp.str = ".--";
+                prev_str = "   |";
+        } else {
+                this_disp.str = "`--";
+                prev->str = prev_str;
+        }
+
+        show_trunks(&this_disp);
+        if ( root->key >= 'A' && root->key <= 'Z' )
+                printf("%c\n", root->key);
+        else
+                printf("%d\n", root->key);
+
+        if (prev) prev->str = prev_str;
+        this_disp.str = "   |";
+
+        show_tree(root->left, &this_disp, 0);
+        if (!prev) puts("");
+}
+