#include <bits/stdc++.h>
using namespace std;

int main(){
    int n;cin>>n;
    int l=0,r=n;
    int ctl=1,ctr=n;
    for(int i=0;i<10;i++){
        int c=(l+r)/2;
        cout<<"? "<<c+1<<"\n";
        int ct;cin>>ct;
        if(ct-ctl<c-l){
            ctr=ct;
            r=c;
        }else{
            ctl=ct;
            l=c;
        }
    }
    cout<<"Yes "<<ctl<<" "<<ctl+1<<"\n";
}