"""Телефонный справочник на трёх структурах данных."""


def _node(name, phone, next_node=None):
    return {"name": name, "phone": phone, "next": next_node}


def ll_insert(head, name, phone):
    """Добавить запись в конец списка или обновить существующую."""
    if head is None:
        return _node(name, phone)

    current = head
    while True:
        if current["name"] == name:
            current["phone"] = phone
            return head
        if current["next"] is None:
            current["next"] = _node(name, phone)
            return head
        current = current["next"]


def ll_find(head, name):
    current = head
    while current is not None:
        if current["name"] == name:
            return current["phone"]
        current = current["next"]
    return None


def ll_delete(head, name):
    if head is None:
        return None
    if head["name"] == name:
        return head["next"]

    previous, current = head, head["next"]
    while current is not None:
        if current["name"] == name:
            previous["next"] = current["next"]
            break
        previous, current = current, current["next"]
    return head


def ll_list_all(head):
    records = []
    current = head
    while current is not None:
        records.append((current["name"], current["phone"]))
        current = current["next"]
    return sorted(records, key=lambda record: record[0])


def _require_buckets(buckets):
    if not buckets:
        raise ValueError("Хеш-таблица должна содержать хотя бы один бакет")


def _hash_index(name, bucket_count):
    """Хеш-функция."""
    value = 0
    for character in name:
        value = (value * 31 + ord(character)) % bucket_count
    return value


def ht_insert(buckets, name, phone):
    _require_buckets(buckets)
    index = _hash_index(name, len(buckets))
    buckets[index] = ll_insert(buckets[index], name, phone)


def ht_find(buckets, name):
    _require_buckets(buckets)
    return ll_find(buckets[_hash_index(name, len(buckets))], name)


def ht_delete(buckets, name):
    _require_buckets(buckets)
    index = _hash_index(name, len(buckets))
    buckets[index] = ll_delete(buckets[index], name)


def ht_list_all(buckets):
    _require_buckets(buckets)
    records = []
    for head in buckets:
        records.extend(ll_list_all(head))
    return sorted(records, key=lambda record: record[0])


def _bst_node(name, phone):
    return {"name": name, "phone": phone, "left": None, "right": None}


def bst_insert(root, name, phone):
    if root is None:
        return _bst_node(name, phone)

    current = root
    while True:
        if name == current["name"]:
            current["phone"] = phone
            return root
        side = "left" if name < current["name"] else "right"
        if current[side] is None:
            current[side] = _bst_node(name, phone)
            return root
        current = current[side]


def bst_find(root, name):
    current = root
    while current is not None:
        if name == current["name"]:
            return current["phone"]
        current = current["left"] if name < current["name"] else current["right"]
    return None


def bst_delete(root, name):
    parent = None
    current = root
    while current is not None and current["name"] != name:
        parent = current
        current = current["left"] if name < current["name"] else current["right"]
    if current is None:
        return root

    if current["left"] is not None and current["right"] is not None:
        successor_parent = current
        successor = current["right"]
        while successor["left"] is not None:
            successor_parent = successor
            successor = successor["left"]
        current["name"], current["phone"] = successor["name"], successor["phone"]
        parent, current = successor_parent, successor

    child = current["left"] if current["left"] is not None else current["right"]
    if parent is None:
        return child
    if parent["left"] is current:
        parent["left"] = child
    else:
        parent["right"] = child
    return root


def bst_list_all(root):
    records, stack = [], []
    current = root
    while stack or current is not None:
        while current is not None:
            stack.append(current)
            current = current["left"]
        current = stack.pop()
        records.append((current["name"], current["phone"]))
        current = current["right"]
    return records