#include <bits/stdc++.h>

using namespace std;   const int N = 1e5+10;

int l[N], r[N], f[N], m, rt;

int dfs(int x){
	if(!x) return 0;
	int a = dfs(l[x]), b = dfs(r[x]);
	if(a == -1 || b == -1) return -1;
	if(a == 0 && b == 0) return 1;
	int c = m - a - b - 1, o;
	if(a <= m / 2 && b <= m / 2 && c <= m / 2){
		if(min(a, c) >= b){
			cout << "? " << l[x] << ' ' << f[x] << endl;
			cin >> o;
			if(o == 0) m = a, rt = l[x];
			if(o == 1) m = b + 1, l[x] = 0, rt = x;
			if(o == 2) m = c, (x == l[f[x]] ? l[f[x]] : r[f[x]]) = 0;
		}
		else if(min(b, c) >= a){
			cout << "? " << r[x] << ' ' << f[x] << endl;
			cin >> o;
			if(o == 0) m = b, rt = r[x];
			if(o == 1) m = a + 1, r[x] = 0, rt = x;
			if(o == 2) m = c, (x == l[f[x]] ? l[f[x]] : r[f[x]]) = 0;
		}
		else{
			cout << "? " << l[x] << ' ' << r[x] << endl;
			cin >> o;
			if(o == 0) m = a, rt = l[x];
			if(o == 1) m = c + 1, l[x] = r[x] = 0;
			if(o == 2) m = b, rt = r[x];
		}
		return -1;
	}
	return a + b + 1;
}

int main(){
	int t, n;   cin >> t;
	while(t--){
		cin >> n;   m = rt = 0;
		for(int i = 1; i <= n; i++){
			cin >> l[i] >> r[i];
			f[l[i]] = f[r[i]] = i;
		}
		for(int i = 1; i <= n; i++) if(!f[i]) {rt = i; break;}
		for(m = n; ; dfs(rt)){
			if(m == 1){
				cout << "! " << rt << endl;
				break;
			}
			if(m == 2){
				int x = (l[rt] ? l[rt] : r[rt]), o;
				cout << "? " << rt << ' ' << x << endl;
				cin >> o;
				cout << "! " << (!o ? rt : x) << endl;
				break;
			}
		}
		for(int i = 1; i <= n; i++) l[i] = r[i] = f[i] = 0;
	}
	return 0;
}