119 lines
2.9 KiB
Python
119 lines
2.9 KiB
Python
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from typing import Any, Dict, List, Optional
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Node = Dict[str, Any]
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def _make_node(name: str, phone: str) -> Node:
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return {"name": name, "phone": phone, "left": None, "right": None}
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def bst_insert(root: Optional[Node], name: str, phone: str) -> Node:
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new_node = _make_node(name, phone)
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if root is None:
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return new_node
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current = root
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parent = None
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while current is not None:
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parent = current
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if name < current["name"]:
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current = current["left"]
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elif name > current["name"]:
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current = current["right"]
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else:
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current["phone"] = phone
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return root
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if name < parent["name"]:
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parent["left"] = new_node
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else:
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parent["right"] = new_node
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return root
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def bst_find(root: Optional[Node], name: str) -> Optional[str]:
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current = root
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while current is not None:
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if name < current["name"]:
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current = current["left"]
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elif name > current["name"]:
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current = current["right"]
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else:
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return current["phone"]
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return None
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def _find_min_node(node: Node) -> Node:
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current = node
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while current["left"] is not None:
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current = current["left"]
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return current
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def bst_delete(root: Optional[Node], name: str) -> Optional[Node]:
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if root is None:
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return None
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parent = None
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current = root
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while current is not None and current["name"] != name:
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parent = current
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if name < current["name"]:
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current = current["left"]
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else:
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current = current["right"]
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if current is None:
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return root
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if current["left"] is None or current["right"] is None:
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child = current["left"] if current["left"] is not None else current["right"]
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if parent is None:
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return child
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if parent["left"] is current:
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parent["left"] = child
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else:
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parent["right"] = child
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return root
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succ_parent = current
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successor = current["right"]
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while successor["left"] is not None:
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succ_parent = successor
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successor = successor["left"]
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current["name"] = successor["name"]
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current["phone"] = successor["phone"]
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successor_child = successor["right"]
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if succ_parent["left"] is successor:
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succ_parent["left"] = successor_child
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else:
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succ_parent["right"] = successor_child
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return root
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def bst_list_all(root: Optional[Node]) -> List[Dict[str, str]]:
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result: List[Dict[str, str]] = []
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stack: List[Node] = []
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current = root
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while current is not None or stack:
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while current is not None:
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stack.append(current)
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current = current["left"]
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current = stack.pop()
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result.append({"name": current["name"], "phone": current["phone"]})
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current = current["right"]
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return result
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