def bst_insert(root: dict | None, name: str, phone: str) -> dict: new_node = {'name': name, 'phone': phone, 'left': None, 'right': None} if root is None: return new_node current = root while True: if name == current['name']: current['phone'] = phone return root if name < current['name']: if current['left'] is None: current['left'] = new_node return root current = current['left'] else: if current['right'] is None: current['right'] = new_node return root current = current['right'] def bst_find(root: dict | None, name: str) -> str | None: current = root while current is not None: if name == current['name']: return current['phone'] if name < current['name']: current = current['left'] else: current = current['right'] return None def bst_min(node: dict) -> dict: while node['left'] is not None: node = node['left'] return node def bst_delete(root: dict | None, name: str) -> dict | None: 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'] successor = bst_min(root['right']) root['name'] = successor['name'] root['phone'] = successor['phone'] root['right'] = bst_delete(root['right'], successor['name']) return root def bst_list_all(root: dict | None) -> list: result = [] def inorder(node): if node is None: return inorder(node['left']) result.append((node['name'], node['phone'])) inorder(node['right']) inorder(root) return result