#include <bits/stdc++.h>
using namespace std;
#define IOS ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
using PII = pair<int, int>;
const int N = 2e5 + 5;
vector<int> G[N];
int siz[N], f[N], vis[N];
int lst = 0;
int mid = 0;
void dfs(int u, int fa)
{
    f[u] = fa;
    siz[u] = 1;
    for (auto v : G[u])
    {
        if (v == fa || vis[v])
            continue;
        dfs(v, u);
        siz[u] += siz[v];
    }
    if (siz[u] == lst / 2)
        mid = u;
}
void delson(int u, int fa)
{
    vis[u] = 1;
    for (auto v : G[u])
    {
        if (v == fa || vis[v])
            continue;
        delson(v, u);
    }
}
void delfa(int u, int fa, int x)
{
    vis[u] = 1;
    for (auto v : G[u])
    {
        if (v == fa || v == x || vis[v])
            continue;
        delfa(v, u, x);
    }
}
void solve()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++)
    {
        int u, v;
        cin >> u >> v;
        if (v)
        {
            G[i].push_back(v);
            G[v].push_back(i);
        }
        if (u)
        {
            G[i].push_back(u);
            G[u].push_back(i);
        }
    }
    lst = n;
    int rt = 1;
    mid = 0;
    while (1)
    {
        int x;
        dfs(rt, 0);
        cerr << mid << endl;
        if (lst == 3)
        {
            for (auto v : G[f[mid]])
            {
                if (vis[v] || v == mid)
                    continue;
                cout << "? " << mid << " " << v << "\n";
                cout.flush();
                cin >> x;
                if (x == 0)
                {
                    cout << "! " << mid << "\n";
                    cout.flush();
                }
                else if (x == 1)
                {
                    cout << "! " << f[mid] << "\n";
                    cout.flush();
                }
                else if (x == 2)
                {
                    cout << "! " << v << "\n";
                    cout.flush();
                }
                return;
            }
        }
        cout << "? " << f[mid] << " " << mid << "\n";
        cout.flush();
        cin >> x;
        if (x == 0)
        {
            delson(mid, f[mid]); // 留父亲 删除儿子及其子树
            rt = f[mid];
            lst -= siz[mid];
        }
        else if (x == 2)
        {
            delfa(1, 0, mid); // 留儿子
            rt = mid;
            lst = siz[mid];
        }
        if (lst == 1)
        {
            cout << "! " << rt << "\n";
            cout.flush();
            return;
        }
    }
    for (int i = 1; i <= n; i++)
    {
        G[i].clear();
        vis[i] = 0;
    }
}
signed main()
{
    IOS;
    int t = 1;
    cin >> t;
    while (t--)
    {
        solve();
    }
    return 0;
}