hash_pointers

M = 100003


class Node:
    def __init__(self, uid, v, next_item=None):
        self.value = [uid, v]
        self.next_item = next_item


def __search_prev_cur__(uid, head):
    if not head:
        return None, None
    if head.value[0] == uid:
        return None, head
    node = head
    while node.next_item and node.next_item.value[0] != uid:
        node = node.next_item
    if node.next_item and node.next_item.value[0] == uid:
        return node, node.next_item
    return None, None


def put(uid, v, head):
    _, node = __search_prev_cur__(uid, head)
    if node:
        node.value[1] = v
    else:
        head = Node(uid, v, next_item=head)
    return None, head


def get(uid, head):
    _, node = __search_prev_cur__(uid, head)
    return node.value[1] if node else False, head


def delete(uid, head):
    prev, node = __search_prev_cur__(uid, head)
    if not node:
        return False, head
    if node == head:
        head = node.next_item
    else:
        prev.next_item = node.next_item
    return node.value[1], head


def process_commands(n):
    hash_table = [None] * M
    for _ in range(n):
        args = (input() + ' 0').split()[:3]
        cmd = args[0]
        uid = int(args[1])
        v = int(args[2])
        bucket = uid % M
        head = hash_table[bucket]
        res, head = {'put': lambda uid, v: put(uid, v, head),
                     'get': lambda uid, _: get(uid, head),
                     'delete': lambda uid, _: delete(uid, head)}[cmd](uid, v)
        [0 if res is None else print(None) if res is False else print(res)]
        hash_table[bucket] = head


n = int(input())
process_commands(n)