1 files changed, 53 insertions, 1 deletions
diff --git a/collect/bst.py b/collect/bst.py
index 8e95fa2..d3231ee 100644
--- a/collect/bst.py
+++ b/collect/bst.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-from typing import Any, Optional
+from typing import Any, List, Optional
 
 
 class Node(object):
@@ -448,6 +448,58 @@ class BinaryTree(object):
     def height(self):
         return self.depth()
 
+    def repr_traverse(self, padding: str, pointer: str, node: Node, has_right_sibling: bool) -> str:
+        if node is not None:
+            self.viz += f'\n{padding}{pointer}{node.value}'
+            if has_right_sibling:
+                padding += "│  "
+            else:
+                padding += '   '
+
+            pointer_right = "└──"
+            if node.right is not None:
+                pointer_left = "├──"
+            else:
+                pointer_left = "└──"
+
+            self.repr_traverse(padding, pointer_left, node.left, node.right is not None)
+            self.repr_traverse(padding, pointer_right, node.right, False)
+
+    def __repr__(self):
+        """
+        Draw the tree in ASCII.
+
+        >>> t = BinaryTree()
+        >>> t.insert(50)
+        >>> t.insert(25)
+        >>> t.insert(75)
+        >>> t.insert(12)
+        >>> t.insert(33)
+        >>> t.insert(88)
+        >>> t.insert(55)
+        >>> t
+        50
+        ├──25
+        │  ├──12
+        │  └──33
+        └──75
+           ├──55
+           └──88
+        """
+        if self.root is None:
+            return ""
+
+        self.viz = f'{self.root.value}'
+        pointer_right = "└──"
+        if self.root.right is None:
+            pointer_left = "└──"
+        else:
+            pointer_left = "├──"
+
+        self.repr_traverse('', pointer_left, self.root.left, self.root.left is not None)
+        self.repr_traverse('', pointer_right, self.root.right, False)
+        return self.viz
+
 
 if __name__ == '__main__':
     import doctest