#include<bits/stdc++.h>
using namespace std;

int main(){
	int data,N;
	int left,right,mid;
	cin >> N;
	vector<int> A(N+1);
	left=1;
	right = N;
	for(int i=0;i<=N;i++){
		A[i] = -1;
	}
	A[0] = 0;
	A[1] = 1;
	A[N] = N-1;
	for(int i=0;i<10;i++){
		mid = (left+right)/2;
		cout << "? " << mid << endl;
		cin >> data;
		A[mid] = data;
		if(A[right]-A[mid] < right-mid){
			left = mid;
		} else {
			right = mid;
		}
	}
	cout << "Yes " << left << " " << right << endl;
	return 0;
}