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реализовано двоичное дерево с помощью функций вставки/обновления, возвращения корня, итеративного поиска, поиска узла с минимальным ключем, рекурсивного удаления, центрированного обхода

novikovsd/hashtab.py

@@ -86,3 +86,74 @@ def ht_list_all(buckets):
             curr = curr['next']
     entries.sort(key=lambda x: x[0])
     return entries
+
+def bst_insert(root, name, phone):
+    new_node = {'name': name, 'phone': phone, 'left': None, 'right': None}
+    if root is None:
+        return new_node
+
+    parent = None
+    curr = root
+    while curr is not None:
+        parent = curr
+        if name < curr['name']:
+            curr = curr['left']
+        elif name > curr['name']:
+            curr = curr['right']
+        else:
+            curr['phone'] = phone
+            return root
+
+    if name < parent['name']:
+        parent['left'] = new_node
+    else:
+        parent['right'] = new_node
+    return root
+
+
+def bst_find(root, name):
+    while root is not None:
+        if name == root['name']:
+            return root['phone']
+        elif name < root['name']:
+            root = root['left']
+        else:
+            root = root['right']
+    return None
+
+
+def _bst_min_node(node):
+    while node and node['left'] is not None:
+        node = node['left']
+    return node
+
+
+def bst_delete(root, name):
+    if root is None:
+        return None
+    if name < root['name']:
+        root['left'] = bst_delete(root['left'], name)
+    elif name > root['name']:
+        root['right'] = bst_delete(root['right'], name)
+    else:
+        if root['left'] is None:
+            return root['right']
+        if root['right'] is None:
+            return root['left']
+        min_node = _bst_min_node(root['right'])
+        root['name'] = min_node['name']
+        root['phone'] = min_node['phone']
+        root['right'] = bst_delete(root['right'], min_node['name'])
+    return root
+
+
+def bst_list_all(root):
+    def inorder(node, res):
+        if node is None:
+            return
+        inorder(node['left'], res)
+        res.append((node['name'], node['phone']))
+        inorder(node['right'], res)
+    result = []
+    inorder(root, result)
+    return result