import sys
sys.setrecursionlimit(5*10**5)
input = sys.stdin.readline
from collections import defaultdict, deque, Counter
from heapq import heappop, heappush
from bisect import bisect_left, bisect_right
from math import gcd

n = int(input())
last = [0,n]
l,r = 1, n+1
cnt = [i for i in range(n)]
for i in range(10):
    m = (l+r)//2
    print("?", m)
    t = int(input())
    if t < m:
        l, r = l,m
    else:
        l, r = m,r

print('Yes', l, r, flush = True)