#include<bits/stdc++.h>
using namespace std;
using i64=long long;
using u64=unsigned long long;
#define ll long long
const int inf=1e9;
const ll inff=1e18;
using i128=__int128;

void solve(){
    int n;
    cin>>n;
    vector<vector<int>> adj(n+1);
    for(int i=0;i<n;i++){
        int x,y;
        cin>>x>>y;
        if(x){
            adj[i+1].emplace_back(x);
            adj[x].emplace_back(i+1);
        }
        if(y){
            adj[i+1].emplace_back(y);
            adj[y].emplace_back(i+1);
        }
    }
    vector<int> siz(n+1);
    vector<int> w(n+1);
    vector<int> vis(n+1);
    int sum=n;
    int ct=-1; //centroid
    auto dfs=[&](auto self,int u,int p)->void{
        siz[u]=1;
        for(int v:adj[u]){
            if(v==p) continue;
            self(self,v,u);
            siz[u]+=siz[v];
        }
    };
    auto get=[&](auto self,int u,int p)->void{
        siz[u]=1;
        w[u]=0;
        for(int v:adj[u]){
            if(v==p || vis[v]) continue;
            self(self,v,u);
            siz[u]+=siz[v];
            w[u]=max(w[u],siz[v]);
        }
        w[u]=max(w[u],sum-siz[u]);
        if(w[u]<=sum/2){
            ct=u;
        }
    };
    get(get,1,0);
    auto ask=[&](auto self,int u)->void{
        dfs(dfs,u,0);
        if(siz[u]==1){
            cout<<"! "<<u<<'\n';
            cout.flush();
            return;
        }
        int v1=0,v2=0,v3=0;
        for(int v:adj[u]){
            if(vis[v]){
                continue;
            }
            if(!v1){
                v1=v;
            }else if(!v2){
                v2=v;
            }else{
                v3=v;
            }
        }
        if(v3){
            if(siz[v1]==min({siz[v1],siz[v2],siz[v3]})){
                swap(v1,v3);
            }
            if(siz[v2]==min({siz[v1],siz[v2],siz[v3]})){
                swap(v2,v3);
            }
            cout<<"? "<<v1<<' '<<v2<<'\n';
            cout.flush();
            int x;
            cin>>x;
            if(x==0){
                int v=v1;
                vis[u]=1;
                sum=siz[v];
                get(get,v,u);
                self(self,ct);
                return;
            }
            if(x==1){
                vis[v1]=vis[v2]=1;
                int v=u;
                sum=siz[v3]+1;
                get(get,u,v1);
                self(self,ct);
                return;
            }
            if(x==2){
                int v=v2;
                vis[u]=1;
                sum=siz[v];
                get(get,v,u);
                self(self,ct);
                return;
            }
        }
        if(v2){
            cout<<"? "<<v1<<' '<<v2<<'\n';
            cout.flush();
            int x;
            cin>>x;
            if(x==0){
                int v=v1;
                vis[u]=1;
                sum=siz[v];
                get(get,v,u);
                self(self,ct);
                return;
            }
            if(x==1){
                cout<<"! "<<u<<'\n';
                cout.flush();
                return;
            }
            if(x==2){
                int v=v2;
                vis[u]=1;
                sum=siz[v];
                get(get,v,u);
                self(self,ct);
                return;
            }
        }
        if(v1){
            cout<<"? "<<v1<<' '<<u<<'\n';
            cout.flush();
            int x;
            cin>>x;
            if(x==0){
                cout<<"! "<<v1<<'\n';
                cout.flush();
                return;
            }
            if(x==2){
                cout<<"! "<<u<<'\n';
                cout.flush();
                return;
            }
        }
    };
    ask(ask,ct);
}

int main(){
    ios::sync_with_stdio(0);cin.tie(0);
    int t=1;
    cin>>t; 
    while(t--){
        solve();
    }
    return 0;
}