import sys

int1 = lambda x: int(x) - 1

# input = lambda: sys.stdin.buffer.readline()
input = lambda: sys.stdin.readline().rstrip()
ii = lambda: int(input())
i1 = lambda: int1(input())
mi = lambda: map(int, input().split())
mi1 = lambda: map(int1, input().split())
li = lambda: list(mi())
li1 = lambda: list(mi1())
lli = lambda n: [li() for _ in range(n)]

INF = float("inf")
mod = int(1e9 + 7)
# mod = 998244353


n = ii()

print("?", 1)
sys.stdout.flush()
a1 = ii()
print("?", n - 1)
sys.stdout.flush()
an = n // 2 - ii()

if a1 != an:
    print("!", 2, n - 1)
    exit(0)


def ask(k):
    print("?", k)
    sys.stdout.flush()
    x = ii()
    if an == 0:
        x = k - x
    return x


l, r = 1, n
for i in range(18):
    m = (l + r) // 2
    x = ask(m)
    if x * 2 == m:
        r = m
        break
    elif x * 2 < m:
        r = m
    elif x * 2 > m:
        l = m
if n // 2 <= r:
    print("!", 1, r)
else:
    print("!", r + 1, n)