#include <bits/stdc++.h>
using namespace std;
int main(){
  int N;
  cin >> N;
  cout << "? " << 1 << endl;
  int S1;
  cin >> S1;
  cout << "? " << N - 1 << endl;
  int S2;
  cin >> S2;
  if (S1 == S2){
    cout << "! " << 2 << ' ' << N - 1 << endl;
  } else {
    int tv = 1, fv = N - 1;
    int p = -1;
    while (fv - tv > 1){
      int mid = (tv + fv) / 2;
      cout << "? " << mid << endl;
      int S;
      cin >> S;
      if (S == 0){
        p = mid;
        break;
      } else if (S1 > 0 && S > 0 || S1 < 0 && S < 0){
        tv = mid;
      } else {
        fv = mid;
      }
    }
    if (p == -1){
      p = tv;
    }
    if (p >= N / 2){
      cout << "! " << 1 << ' ' << p << endl;
    } else {
      cout << "! " << p + 1 << ' ' << N << endl;
    }
  }
}