#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#define popcount __builtin_popcount
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;

int main()
{
    int n; cin>>n;
    int ret;
    int b[200];
    for(int i=1; i<=n/2; i++){
        cout<<"? "<<2*i<<" "<<2*i-1<<endl;
        cin>>ret;
        b[i]=ret;
    }
    if(n&1) b[n/2+1]=n;
    int mx=b[1], mx2=b[2];
    cout<<"? "<<b[1]<<" "<<b[2]<<endl;
    cin>>ret;
    if(ret==b[2]) swap(mx, mx2);
    for(int i=3; i<=(n+1)/2; i++){
        cout<<"? "<<mx2<<" "<<b[i]<<endl;
        cin>>ret;
        if(ret==mx2) continue;
        cout<<"? "<<mx<<" "<<b[i]<<endl;
        cin>>ret;
        if(ret==mx){
            mx2=b[i];
        }else{
            mx2=mx;
            mx=b[i];
        }
    }
    if((n&1) && mx==n){
        cout<<"! "<<mx2<<endl;
    }else{
        int x=(mx+1)/2*4-1-mx;
        cout<<"? "<<mx2<<" "<<x<<endl;
        cin>>ret;
        cout<<"! "<<ret<<endl;
    }
    return 0;
}