def linked_list_add(head, name, phone):
    curr = head
    while curr is not None:
        if curr['name'] == name:
            curr['phone'] = phone
            return head
        curr = curr['next']

    new_node = {'name': name, 'phone': phone, 'next': None}
    if head is None:
        return new_node

    curr = head
    while curr['next'] is not None:
        curr = curr['next']
    curr['next'] = new_node
    return head


def linked_list_find(head, name):
    curr = head
    while curr is not None:
        if curr['name'] == name:
            return curr['phone']
        curr = curr['next']
    return None


def linked_list_remove(head, name):
    if head is None:
        return None
    if head['name'] == name:
        return head['next']
    prev = head
    curr = head['next']
    while curr is not None:
        if curr['name'] == name:
            prev['next'] = curr['next']
            return head
        prev = curr
        curr = curr['next']
    return head


def linked_list_collect_all(head):
    records = []
    curr = head
    while curr is not None:
        records.append((curr['name'], curr['phone']))
        curr = curr['next']
    records.sort(key=lambda pair: pair[0])
    return records



#HASH
def _hash_bucket_index(key, table_size):
    return hash(key) % table_size


def hash_table_create(bucket_count=10):
    return [None] * bucket_count


def hash_table_put(table, name, phone):
    idx = _hash_bucket_index(name, len(table))
    table[idx] = linked_list_add(table[idx], name, phone)
    return table


def hash_table_get(table, name):
    idx = _hash_bucket_index(name, len(table))
    return linked_list_find(table[idx], name)


def hash_table_remove(table, name):
    idx = _hash_bucket_index(name, len(table))
    table[idx] = linked_list_remove(table[idx], name)
    return table


def hash_table_collect_all(table):
    all_records = []
    for head in table:
        curr = head
        while curr is not None:
            all_records.append((curr['name'], curr['phone']))
            curr = curr['next']
    all_records.sort(key=lambda pair: pair[0])
    return all_records


#BST
def _bst_new_node(name, phone):
    return {'name': name, 'phone': phone, 'left': None, 'right': None}


def bst_add(root, name, phone):
    """Insert or update. Returns (possibly new) root."""
    if root is None:
        return _bst_new_node(name, phone)

    if name == root['name']:
        root['phone'] = phone
    elif name < root['name']:
        root['left'] = bst_add(root['left'], name, phone)
    else:
        root['right'] = bst_add(root['right'], name, phone)
    return root


def bst_find(root, name):
    if root is None:
        return None
    if name == root['name']:
        return root['phone']
    elif name < root['name']:
        return bst_find(root['left'], name)
    else:
        return bst_find(root['right'], name)


def _bst_find_minimum(node):
    while node['left'] is not None:
        node = node['left']
    return node


def bst_remove(root, name):
    if root is None:
        return None

    if name < root['name']:
        root['left'] = bst_remove(root['left'], name)
    elif name > root['name']:
        root['right'] = bst_remove(root['right'], name)
    else:
        if root['left'] is None:
            return root['right']
        if root['right'] is None:
            return root['left']

        successor = _bst_find_minimum(root['right'])
        root['name'] = successor['name']
        root['phone'] = successor['phone']
        root['right'] = bst_remove(root['right'], successor['name'])
    return root


def bst_collect_inorder(root):
    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


if __name__ == '__main__':
    tree = None
    tree = bst_add(tree, 'Zoe', '111')
    tree = bst_add(tree, 'Alice', '222')
    tree = bst_add(tree, 'Bob', '333')
    tree = bst_add(tree, 'Alice', '444')
    print(bst_find(tree, 'Alice'))   # 444
    tree = bst_remove(tree, 'Bob')
    print(bst_collect_inorder(tree)) # [('Alice','444'), ('Zoe','111')]