I = [min(1 << i, 10 ** 6) for i in range(21)]

for _ in range(int(input())):
    print('? 1 0')
    r0 = int(input())
    print('? 1 1')
    r1 = int(input())
    k = r1 - r0
    def f(x):
        print(f'? 1 {x}')
        res = int(input())
        return res - r0 - k * x
    if not f(I[-1]):
        # m | n
        assert k > 0
        if k == 1:
            # m = n
            print('? 2 0')
            r = int(input())
            # 2r or 2r+1
            print('? 2 1')
            t = int(input())
            n = 2 * r if r == t else 2 * r + 1
            print('!', n)
        else:
            sm = k * (k - 1) // 2
            assert sm > 0 and r0 % sm == 0
            m = r0 // sm
            n = m * k
            print('!', n)
        continue
    l = 0
    r = 20
    memo = [-1] * 21
    while r - l > 1:
        c = (l + r) // 2
        memo[c] = f(I[c])
        if memo[c]:
            r = c
        else:
            l = c
    unit = k * (k + 1) // 2
    d = I[r] - memo[r]
    sm = r0 + k * unit
    assert sm % unit == 0
    m = sm // unit
    n = m * (k + 1) - d
    print('!', n)
    if int(input()) == -1:
        break