#include<iostream>
#include<random>
#include<vector>
#include<algorithm>
#include<set>
using namespace std;
void ask(int x, int y){
    cout<<"? "<<x<<" "<<y<<endl;
}
int main(){
    int n; cin>>n;
    int ret;
    if(n<=168){
        int mx=1, mx2=2;
        ask(1, 2);
        cin>>ret;
        if(ret==2) swap(mx, mx2);
        for(int i=3; i<=n; i++){
            ask(i, mx2);
            cin>>ret;
            if(ret==mx2) continue;
            ask(i, mx);
            cin>>ret;
            if(ret==mx){
                mx2=i;
            }else{
                mx2=mx;
                mx=i;
            }
        }
        cout<<"! "<<mx2<<endl;
        return 0;
    }
    int d=(int)sqrt((double)(2*n));
    int t=0;
    int v=-1;
    set<int> st;
    while(t<d){
        int r=rand()%n+1;
        if(st.find(r)!=st.end()) continue;
        st.insert(r);
        if(v==-1) v=r;
        else{
            ask(v, r);
            cin>>ret;
            v=ret;
        }
        t++;
    }
    vector<int> vec;
    for(int i=1; i<=n; i++){
        if(st.find(i)!=st.end()) continue;
        ask(v, i);
        cin>>ret;
        if(ret==i) vec.push_back(i);
    }
    int mx=v, mx2=vec[0];
    ask(mx, mx2); cin>>ret;
    if(ret==mx2) swap(mx, mx2);
    for(int i=1; i<vec.size(); i++){
        ask(mx2, vec[i]);
        cin>>ret;
        if(ret==mx2) continue;
        ask(mx, vec[i]);
        cin>>ret;
        if(ret==mx) mx2=vec[i];
        else{
            mx2=mx;
            mx=vec[i];
        }
    }
    cout<<"! "<<mx2<<endl;
    return 0;
}