N = int(input())
left = 1
right = N + 1
for _ in range(10):
    if right - left > 2:
        mid = (left + right) >> 1
        print("?", mid)
        x = int(input())
        if x >= mid:
            left = mid
        else:
            right = mid + 1

print("Yes", left, right - 1)