#include<bits/stdc++.h>
using namespace std;
typedef int ll;
typedef pair<ll,ll> PII;
typedef pair<ll,PII> PIII;
#define x first
#define y second
const ll N =2e5+100,M=N,INF = 1e18;
ll n,m,k;
multiset<ll> v[N];
ll root=-1;
ll sz[N];
ll ans=1e9;
ll dfszx(ll u,ll fa,ll pp){
    ll sum=1,res=0;
    for(auto j:v[u]){
        if(j!=fa){
            ll s=dfszx(j,u,pp);
            res=max(res,s);
            sum+=s;
        }
    }
    res=max(res,pp-sum);
    if(res<ans){
        ans=res;
        root=u;
    }
    return sum;
}
void dfs(ll u,ll fa){
	sz[u]=1;
	for(auto j:v[u]){
		if(j!=fa){
			dfs(j,u);
			sz[u]+=sz[j];
		}
	}
}
bool cmp(ll x,ll y){
	return sz[x]>=sz[y];
}
void solve(){
	cin>>n;
	for(ll i=1;i<=n;i++) v[i].clear();
	root=-1;
	for(ll i=1;i<=n;i++){
		ll x,y;cin>>x>>y;
		if(x) v[i].insert(x),v[x].insert(i);
		if(y) v[i].insert(y),v[y].insert(i);
	}
	ll pp=1;
	ll szz=n;
	while(1){
		ans=1e9;
	    dfszx(pp,-1,szz);
	    dfs(root,-1);
	    if(v[root].size()==1){
	    	cout<<"? "<<root<<" "<<*v[root].begin()<<endl;
	    	ll x;cin>>x;
	    	if(x==0) cout<<"! "<<root<<endl;
	    	else cout<<"! "<<*v[root].begin()<<endl;
	    	return ;
	    }
	    else if(v[root].size()==2){
	    	ll p1=*v[root].begin(),p2=*(--v[root].end());
	    	cout<<"? "<<p1<<" "<<p2<<endl;
	    	ll x;cin>>x;
	    	if(x==0){
	    		pp=p1;
	    		szz=sz[pp];
	    		v[pp].erase(root);
	    	}
	    	else if(x==1){
	    		cout<<"! "<<root<<endl;
	    		return ;
	    	}
	    	else{
	    		pp=p2;
	    		szz=sz[pp];
	    		v[pp].erase(root);
	    	}
	    }
	    else{
	    	vector<ll> pl;
	    	for(auto j:v[root]) pl.push_back(j);
	    	sort(pl.begin(),pl.end(),cmp);
	    	cout<<"? "<<pl[0]<<" "<<pl[1]<<endl;
	    	ll x;cin>>x;
	    	if(x==0){
	    		pp=pl[0];
	    		szz=sz[pp];
	    		v[pp].erase(root);
	    	}
	    	else if(x==1){
	    		pp=root;
	    		szz=sz[pl[2]]+1;
	    		v[pp].erase(pl[0]);
	    		v[pp].erase(pl[1]);
	    	}
	    	else if(x==2){
	    		pp=pl[1];
	    		szz=sz[pp];
	    		v[pp].erase(root);
	    	}
	    }
	}
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	ll __=1;cin>>__;
    while(__--) solve();
    return 0;
}