#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
#define Inf 1000000001

void answer(int n){
	cout<<"! 1 "<<n<<endl;
	exit(0);
}

int query(int N){
	cout<<"? "<<N<<endl;
	int ret;
	cin>>ret;
	if(ret*2 == N){
		answer(N);
	}
	return ret;
}


int main(){
	int N;
	cin>>N;
	int sum = query(N-1);
	
	int ok = N-1;
	int ng = 0;
	
	while(ok-ng>1){
		int mid = (ok+ng)/2;
		int ret=  query(mid);
		if(sum!=N/2){
			if(N/2 != mid-ret)ng = mid;
			else ok = mid;
		}
		else{
			if(N/2 != ret)ng = mid;
			else ok = mid;
		}
	}
	cout<<"! "<<ok<<' '<<ok+1<<endl;
	
	return 0;
}