X-Git-Url: https://wannabe.guru.org/gitweb/?a=blobdiff_plain;f=collect%2Fbst.py;h=d39419494d3f482712f17e13a5ff6ce1e7c2ebcf;hb=532df2c5b57c7517dfb3dddd8c1358fbadf8baf3;hp=9d6525946e8131728896d86f3400c38c5ba528e7;hpb=6ba90a1f30f1c0cf4df12fcd0c62181f29bc3668;p=python_utils.git

diff --git a/collect/bst.py b/collect/bst.py
index 9d65259..d394194 100644
--- a/collect/bst.py
+++ b/collect/bst.py
@@ -1,5 +1,9 @@
 #!/usr/bin/env python3
 
+# © Copyright 2021-2022, Scott Gasch
+
+"""Binary search tree."""
+
 from typing import Any, Generator, List, Optional
 
 
@@ -90,9 +94,7 @@ class BinarySearchTree(object):
             return self._find(value, node.right)
         return None
 
-    def _parent_path(
-        self, current: Optional[Node], target: Node
-    ) -> List[Optional[Node]]:
+    def _parent_path(self, current: Optional[Node], target: Node) -> List[Optional[Node]]:
         if current is None:
             return [None]
         ret: List[Optional[Node]] = [current]
@@ -520,12 +522,12 @@ class BinarySearchTree(object):
             return x
 
         path = self.parent_path(node)
-        assert path[-1]
+        assert path[-1] is not None
         assert path[-1] == node
         path = path[:-1]
         path.reverse()
         for ancestor in path:
-            assert ancestor
+            assert ancestor is not None
             if node != ancestor.right:
                 return ancestor
             node = ancestor
@@ -575,7 +577,11 @@ class BinarySearchTree(object):
         return self.depth()
 
     def repr_traverse(
-        self, padding: str, pointer: str, node: Optional[Node], has_right_sibling: bool
+        self,
+        padding: str,
+        pointer: str,
+        node: Optional[Node],
+        has_right_sibling: bool,
     ) -> str:
         if node is not None:
             viz = f'\n{padding}{pointer}{node.value}'
@@ -590,9 +596,7 @@ class BinarySearchTree(object):
             else:
                 pointer_left = "└──"
 
-            viz += self.repr_traverse(
-                padding, pointer_left, node.left, node.right is not None
-            )
+            viz += self.repr_traverse(padding, pointer_left, node.left, node.right is not None)
             viz += self.repr_traverse(padding, pointer_right, node.right, False)
             return viz
         return ""
@@ -628,9 +632,7 @@ class BinarySearchTree(object):
         else:
             pointer_left = "├──"
 
-        ret += self.repr_traverse(
-            '', pointer_left, self.root.left, self.root.left is not None
-        )
+        ret += self.repr_traverse('', pointer_left, self.root.left, self.root.left is not None)
         ret += self.repr_traverse('', pointer_right, self.root.right, False)
         return ret