CF 2E 求条

#include<bits/stdc++.h>
using namespace std;
#define PII pair<int,int>
#define PLI pair<ll,int>
#define PIL pair<int,ll>
#define PLL pair<ll,ll>
#define fi first
#define se second
#define YES() cout<<"YES\n",0
#define NO() cout<<"NO\n",0
#define Yes() cout<<"Yes\n",0
#define No() cout<<"No\n",0
using ll=long long;
using uint=unsigned int;
using ull=unsigned long long;
using lb=long double;
const int N=555;
int T;
ll n,c[N],p[N],lst[N],vis[N],in[N];
vector<PLL>ans;
int main(){
    cin>>T;
    while(T--){
        cin>>n;ans.clear();
        for(int i=1;i<=n;i++)   c[i]=p[i]=lst[i]=vis[i]=in[i]=0;
        in[1]=1;
        for(ll i=2;;){
            cout<<"? "<<i<<endl;
            int x;
            cin>>x;
            if(x==-1)   assert(0);
            if(!x)  break;
            for(int j=1;j<=x;j++){
                cin>>p[j];
                if(!in[p[j]])   in[p[j]]=i;
            }
            for(int j=1;j<=n;j++){
                p[j]*=(j<=x);
                if(!vis[lst[j]]&&p[j]!=lst[j])  vis[lst[j]]=1,c[lst[j]]=i-in[lst[j]];
                lst[j]=p[j];
            }
            //for(int j=1;j<=n;j++) cerr<<vis[j]<<" ";cerr<<"\n";
            for(int j=1;j<x;j++)    ans.push_back({p[j],p[j+1]});
            if(vis[p[x]])   i+=c[p[x]];
            else    i++;
        }
        sort(ans.begin(),ans.end());
        ans.resize(unique(ans.begin(),ans.end())-ans.begin());
        cout<<"! "<<ans.size()<<endl;
        for(auto it:ans)    cout<<it.fi<<" "<<it.se<<endl;
    }
}