N = int(input())

left = 0
right = N - 1

while right - left > 1:
    m = (left + right) // 2

    print("? {}".format(m + 1))
    a = int(input())

    if a < m + 1:
        right = m
    else:
        left = m

print("Yes {} {}".format(left + 1, right + 1))