#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#define _GLIBCXX_DEBUG
using namespace std;
using std::cout;
using std::cin;
using std::endl;
using ll=long long;
using ld=long double;
ll ILL=1167167167167167167;
const int INF=2100000000;
const ll mod=998244353;
#define rep(i,a) for (ll i=0;i<a;i++)
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> ll LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> ll UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,const T &b){if(a>b){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,const T &b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
void yneos(bool a){if(a) cout<<"Yes\n"; else cout<<"No\n";}

void out(int a){
	cout<<"? "<<a<<endl;
}

void solve();

//  rainy ~ 雨に打たれて ~
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int t=1;
	//cin>>t;
	rep(i,t) solve();
}

void solve(){
	int N;
	cin>>N;
	int a,b,l=1,r=N-1;
	out(l);
	cin>>a;
	out(r);
	cin>>b;
	a=(a*2)-l;
	b=(b*2)-r;
	if(a==b){
		cout<<"! "<<l+1<<" "<<r<<endl;
		return ;
	}
	while(r-l>1){
		int med=(l+r)/2;
		out(med);
		int x;
		cin>>x;
		x=(x*2-med);
		if(x==0){
			l=med;
			break;
		}
		if((a<0)^(x<0)) r=med;
		else l=med;
	}
	if(l<N/2) cout<<"! "<<l+1<<" "<<N<<endl;
	else cout<<"! 1 "<<l<<endl;
}