#include "bits/stdc++.h"

using namespace std;

#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(ll i = m;i < n;i++)
#define FORR(i, m, n) for(ll i = m;i >= n;i--)
#define REPO(i, n) for(ll i = 1;i <= n;i++)
#define ll long long
#define INF (ll)1ll << 60
#define MINF (-1 * INF)
#define ALL(n) n.begin(),n.end()
#define MOD (ll)1000000007
#define P pair<int, int>


vector<vector<int>> g;
vector<int> sz, used;
void dfs_sz(int nv, int np) {
	stack<P> st;
	st.push(P(nv - 1000000, np));
	st.push(P(nv, np));

	while(!st.empty()){
		P tp = st.top();
		st.pop();
		ll v = tp.first, p = tp.second;
		if(v >= 0){
			for(auto& i: g[v]) {
				if(used[i] or i == p)continue;
				st.push(P(i - 1000000, v));
				st.push(P(i, v));
			}
		}
		else{
			v += 1000000;
			sz[v] = 1;
			for(auto& i: g[v]) {
				if(used[i] or i == p)continue;
				sz[v] += sz[i];
			}
		}
	}
}

P dfs_search(int nv, int np, int nsz){
	stack<P> st;

	st.push(P(nv, np));

	while(!st.empty()){
		ll now = -1;
		P tp = st.top();
		st.pop();
		ll v = tp.first, p = tp.second;
		bool ok = false;
		for(auto& i: g[v]) {
			if(used[i] or i == p)continue;
			if(sz[i] > nsz / 2){
				ok = true;
				st.push(P(i, v));
			}
			if(sz[i] * 2 == nsz) now = i;
		}
		if(!ok){
			return P(v, now);
		}
	}
	return P(nv, -1);
}

void dfs_used(int nv, int np){
	stack<P> st;

	st.push(P(nv, np));
	while(!st.empty()){
		P tp = st.top();
		st.pop();
		ll v = tp.first, p = tp.second;
		used[v] = true;
		for(auto& i: g[v]) {
			if(i == p or used[i])continue;
			st.push(P(i, v));
		}
	}
}

ll query(P p){
	// 2
	if(p.second != -1){
		cout << "? " << p.first + 1 << " " << p.second + 1 << endl;
		int a;
		cin >> a;
		if(a == 0){
			dfs_used(p.second, p.first);
			return p.first;
		}
		else {
			dfs_used(p.first, p.second);
			return p.second;
		}
	}
	// 3
	int v = p.first;
	vector<int> h;
	for(auto& i: g[v]) {
		if(used[i])continue;
		h.push_back(i);
	}
	//3-0(goal)
	if(h.size() == 0) return v - 1000000;
	else if(h.size() == 1) { // 3-1
		return query(P(v, h[0]));
	}
	else { // 3 - 2, 3
		cout << "? " << h[0] + 1 <<" " << h[1] + 1<< endl;
		int a;
		cin >> a;
		if(a == 0){ //h[0]
			dfs_used(v, h[0]);
			return h[0];
		}
		else if(a == 1){
			dfs_used(h[0], v);
			dfs_used(h[1], v);
			return v;
		}
		else {//h1
			dfs_used(v, h[1]);
			return h[1];
		}
	}
}

ll solve2(int v){
	dfs_sz(v, -1);
	ll nsz = sz[v];
	P d = dfs_search(v, -1, nsz);
	ll nx = query(d);
	if(nx < 0) return nx + 1000000;
	return solve2(nx);
}
void solve(ll n){
	g.resize(0);
	sz.resize(0);
	used.resize(0);

	g.resize(n + 10);
	sz.resize(n + 10);
	used.resize(n + 10);
	REP(i, n){
		ll a, b;
		cin >> a >> b;
		a--;
		b--;
		if(a != -1) {
			g[i].push_back(a);
			g[a].push_back(i);
		}
		if(b != -1) {
			g[i].push_back(b);
			g[b].push_back(i);
		}
		//ok
	}
	ll res = solve2(0);
	cout << "! " << res + 1 << endl;
}

int main() {
	ll tt;
	cin >> tt;
	REP(i, tt){
		ll n;
		cin >> n;
		solve(n);
	}
}