#include<bits/stdc++.h>
#define int long long
using namespace std;
using ll = long long;
using ld = double;
const ll mod = 1e9 + 7;
const ll inf = 1e18 + 5;
const int N = 1e6 + 5;
vector<vector<int> >ed;	//存边
vector<int>siz,mxsiz,vis;	//siz存每个以x为根的子树大小，mxsiz存每个x的儿子的最大子树
int qans;
void init(int n){			//qans存重心
    siz=mxsiz=vector<int>(n+5);
}
void dfs(int x,int fa,int n){
    siz[x]=1;
    mxsiz[x]=0;
    for(auto son:ed[x]){
        if(son==fa||vis[son])continue;
        dfs(son,x,n);
        siz[x]+=siz[son];
        mxsiz[x]=max(mxsiz[x],siz[son]);
    }
    mxsiz[x]=max(mxsiz[x],n-siz[x]);
    if(mxsiz[x]<=n/2){
        qans=x;
    }
}
void solve(){
    int n;
    cin>>n;
    ed=vector<vector<int> >(n+5);
    vis=vector<int>(n+5);
    for(int i=1;i<=n;i++){
        int a,b;
        cin>>a>>b;
        if(a){
            ed[i].push_back(a);
            ed[a].push_back(i);
        }
        if(b){
            ed[i].push_back(b);
            ed[b].push_back(i);
        }
    }
    int n1=n,now=1;
    while(n1>2){
        init(n);
        dfs(now,0,n1);
        int mx=0,pos=0,pos1=0;
        now=qans;
        init(n);
        dfs(now,0,n1);
        for(auto son:ed[now]){
            if(mx<siz[son]){
                mx=siz[son];
                pos=son;
            }
        }
        for(auto son:ed[now]){
            if(pos!=son){
                pos1=son;
                break;
            }
        }
        cout<<"? "<<pos<<' '<<pos1<<endl;
        int op;
        cin>>op;
        if(op==0){
            vis[now]=1;
            now=pos;
            n1=siz[pos];
        }else if(op==1){
            vis[pos]=vis[pos1]=1;
            n1=n1-siz[pos]-siz[pos1];
        }else{
            vis[now]=1;
            now=pos1;
            n1=siz[pos1];
        }
    }
    if(n1==2){
        int pos=0;
        for(auto son:ed[now]){
            if(!vis[son]){
                pos=son;
                break;
            }
        }
        cout<<"? "<<pos<<' '<<now<<endl;
        int op;
        cin>>op;
        if(op==0){
            cout<<"! "<<pos<<endl;
        }else{
            cout<<"! "<<now<<endl;
        }
    }else{
        cout<<"! "<<now<<endl;
    }
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
//    cout<<fixed<<setprecision(6);
//    srand(time(0));
    int T = 1;
    cin >> T;
    while (T--)solve();
    return 0;
}