#include<bits/stdc++.h>

using namespace std;
#define int long long
vector<vector<int>> q;
vector<int> fa1;

int js(int a, int b) {
    cout << "? " << a << " " << b << endl;
    int x;
    cin >> x;
    return x;
}

vector<int> ma, vis, siz;
int ans1 = 0, ans2 = 0;
int id1, id2;
int num = 0;

void dfs(int u, int fa) {
    num++;
    siz[u] = 1;
    ma[u] = 0;
    for (auto j: q[u]) {
        if (j == fa || vis[j])continue;
        dfs(j, u);
        siz[u] += siz[j];
        ma[u] = max(siz[j], ma[u]);
    }
}

void dfs2(int u, int fa) {
    ma[u] = max(ma[u], num - siz[u]);
    for (auto j: q[u]) {
        if (j == fa || vis[j])continue;
        dfs2(j, u);
    }
    if (ans1 > ma[u]) {
        ans1 = ma[u];
        id1 = u;
    }

}

void solve() {
    int n;
    cin >> n;
    siz = vis = ma = fa1 = vector<int>(n + 5);

    q = vector<vector<int>>(n + 5);
    for (int i = 1, a, b; i <= n; i++) {
        cin >> a >> b;
        if (a) {
            q[i].push_back(a);
            q[a].push_back(i);
        }
        if (b) {
            q[i].push_back(b);
            q[b].push_back(i);
        }
    }
    ans1 = 0, ans2 = 0;
    num = 0;
    ans1 = 1e9;
    dfs(1, 0);
    dfs2(1, 0);
    int cnt = 0;
    int fa1 = id1;
    for (int i = 0; i < q[id1].size(); i++) {
        int y = q[id1][i];
        if (vis[y])continue;
        cnt++;
        if (cnt == 1) {
            id2 = y;
        } else if (cnt == 2) {
            id1 = y;
        }
    }
    int q1 = js(id1, id2);

    while (1) {
        if (q1 == 0) {
            if (cnt >=2) {
                vis[fa1] = 1;
            } else if (cnt == 1) {
                vis[id2] = 1;
            }
        } else if (q1 == 2) {
            if (cnt >= 2) {
                vis[fa1] = 1;
            } else if (cnt == 1) {
                vis[id1] = 1;
            }
            id1 = id2;
        } else {
            vis[id1] = 1, vis[id2] = 1;
            id1 = fa1;
        }
        num = 0;
        ans1 = 1e9;
        dfs(id1, 0);
        if (num == 1) {
            cout << "!" << " " << id1 << endl;
            return;
        }
        dfs2(id1, 0);
        cnt = 0;
        fa1 = id1;
        for (int i = 0; i < q[id1].size(); i++) {
            int y = q[id1][i];
            if (vis[y])continue;
            cnt++;
            if (cnt == 1) {
                id2 = y;
            } else if (cnt == 2) {
                id1 = y;
            }
        }
        q1 = js(id1, id2);
    }


}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr), cout.tie(nullptr);
    int T = 1;
    cin >> T;
    while (T--) solve();
    return 0;
}