def fast_bitwise_and(S):
    if len(S) == 0:
        return -1

    MAX_BITS = 32
    count = [0] * MAX_BITS

    for num in S:
        for bit in range(MAX_BITS):
            if num & (1 << bit):
                count[bit] += 1

    result = 0
    for bit in range(MAX_BITS):
        if count[bit] == len(S):
            result |= (1 << bit)

    return result

Q = int(input().strip())
S = set()
for _ in range(Q):
    query = list(map(int, input().strip().split()))
    if query[0] == 1:
        S.add(query[1])
    elif query[0] == 2:
        if query[1] in S:
            S.remove(query[1])
    elif query[0] == 3:
        print(fast_bitwise_and(S))