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

int main(){
  int t=0;
  int n;
  cin>>n;
  auto query=[&](vector<int> a,vector<int> b){
    int ka=a.size(),kb=b.size();
    if (ka==0||kb==0) return 0;
    cout<<"? "<<ka<<" "<<kb;
    for (int i=0;i<ka;i++) cout<<" "<<a[i]+1;
    for (int i=0;i<kb;i++) cout<<" "<<b[i]+1;
    cout<<endl;
    int r;
    cin>>r;
    //assert(r!=-1);
    ++t;
    return r;
  };
  vector<pair<int,int>> ans;
  for (int i=0;i<n;i++){
    int l=i+1,r=n;
    while (true){
      {
        vector<int> b;
        for (int j=l;j<n;j++) b.push_back(j);
        if (!query({i},b)) break;
      }
      while (r-l>1){
        int mid=(l+r)/2;
        vector<int> b;
        for (int j=l;j<mid;j++) b.push_back(j);
        if (query({i},b)) r=mid;
        else l=mid;
      }
      ans.push_back({i,r-1});
      l=r;
      r=n;
    }
  }
  int m=ans.size();
  assert(t<=10*m+n);
  cout<<"! "<<m<<endl;
  for (int i=0;i<m;i++) cout<<ans[i].first+1<<" "<<ans[i].second+1<<endl;
}