#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ls(p) (p<<1)
#define rs(p) (p<<1|1)
#define mid ((l+r)>>1)
void solve()
{
	int n;cin>>n;
	vector<vector<int> > eg(n+1);
	for(int i=1;i<=n;++i)
	{
		int x,y;
		cin>>x>>y;
		if(x)
		{
			eg[x].emplace_back(i);
			eg[i].emplace_back(x);
		}
		if(y)
		{
			eg[y].emplace_back(i);
			eg[i].emplace_back(y);
		}
	}
	vector<int> str(n+1),son(n+1),vis(n+1);
	int tot=n;
	int rt=0;
	son[0]=n+1;
	function<void(int,int)> find=[&](int now,int fa) -> void
	{
		str[now]=1;
		son[now]=0;
		for(int t:eg[now])
		{
			if(t==fa||vis[t]) continue;
			find(t,now);
			str[now]+=str[t];
			son[now]=max(son[now],str[t]);
		}
		son[now]=max(son[now],tot-str[now]);
		if(son[now]<son[rt])
		{
			rt=now;
		}
	};
	function<void(int,int)> dfs2=[&](int now,int fa) -> void
	{
		str[now]=1;
		for(int t:eg[now])
		{
			if(t==fa||vis[t]) continue;
			find(t,now);
			str[now]+=str[t];
		}
	};
	function<void(int,int)> clear=[&](int now,int fa) -> void
	{
//		cout<<now<<"!!!!!!!!"<<endl;
		vis[now]=1;
		--tot;
		for(int t:eg[now])
		{
			if(t==fa||vis[t]) continue;
			clear(t,now);
		}
	};	
	int cur = 1;
	while(tot>1)
	{
		if(tot==2)
		{
			int x=0,y=0;
			for(int i=1;i<=n;++i)
			{
				if(!vis[i])
				{
					if(!x) x=i;
					else y=i;
				}
			}
			cout<<"? "<<x<<' '<<y<<endl;
			int o;cin>>o;
			if(o==0)
			{
				cout<<"! "<<x<<endl;
				return;
			}
			else
			{
				cout<<"! "<<y<<endl;
				return;
			}
		}
		rt=0;
		find(cur,0);
		dfs2(rt,0);
		vector<int> tmp;
		for(int x:eg[rt])
		{
			if(vis[x]) continue;
			tmp.emplace_back(x);
		}
		sort(tmp.begin(),tmp.end(),[&](int a,int b){
			return str[a]>str[b];
		});
		
		cout<<"? "<<tmp[0]<<' '<<tmp[1]<<endl;
		int o;cin>>o;
		if(o==0)
		{
			clear(rt,tmp[0]);
			cur = tmp[0];
		}
		if(o==1)
		{
			clear(tmp[0],rt);
			clear(tmp[1],rt);
			cur = rt;
//			cout<<tot<<"!!!!!!!!!"<<endl;
		}
		if(o==2)
		{
			clear(rt,tmp[1]);
			cur = tmp[1];
		}
	}
	for(int i=1;i<=n;++i)
	{
		if(!vis[i])
		{
			cout<<"! "<<i<<endl;
			return;
		}
	}
}
signed main()
{
	// ios::sync_with_stdio(0);
	// cin.tie(0);
	int T=1;
	cin>>T;
	while(T--) solve();
	return 0;
}