#include <bits/stdc++.h>
using namespace std;
int main () {
	int N;
	cin >> N;
	int ok = 1, ng = N;
	for (int pkj = 0; pkj < 10; pkj ++) {
		if (abs(ok - ng) > 1) {
			int mu = (ok + ng) / 2;
			cout << "? " << mu << endl;
			int a;
			cin >> a;
			if (a < mu) {
				ng = mu;
			} else {
				ok = mu;
			}
		} else {
			cout << "? 1" << endl;
			int a;
			cin >> a;
		}
	}
	cout << "Yes " << ok << " " << ok + 1 << endl;
}