#include "bits/stdc++.h"
using namespace std;

#define ll long long 
#define INF 0x3f3f3f3f
#define LNF 0x3f3f3f3f3f3f3f3fll
#define MOD 998244353
#define pii pair<int, int>

#define N 100010
#define K 20

int vld[N], f[N], sz[N], w[N], ind[N];
vector<int> G[N];

void add_edge(int u, int v) {
    G[u].emplace_back(v);
    G[v].emplace_back(u);
}

int dfs(int u, int fa) {
    sz[u] = 1;
    for (auto v : G[u]) {
        if (v == fa || !vld[v]) continue;
        sz[u] += dfs(v, u);
    }
    return sz[u];
}

void center(int u, int fa, int psz, int& ans) {
    w[u] = psz ++;
    for (auto v : G[u]) {
        if (v == fa || !vld[v]) continue;
        psz += sz[v];
        w[u] = max(w[u], sz[v]);
    }
    if (ans == -1 || w[u] < w[ans]) ans = u;
    for (auto v : G[u]) {
        if (v == fa || !vld[v]) continue;
        center(v, u, psz - sz[v], ans);
    }
}

void fg(int u, int fa, int flag) {
    f[u] = flag;
    for (auto v : G[u]) {
        if (v == fa || !vld[v]) continue;
        fg(v, u, flag);
    }
}

int query(int u, int v) {
    cout << "? " << u << ' ' << v << '\n';
    cout.flush();
    int res; cin >> res;

    if (res == -1) {
        cout << "ask " << u << ' ' << v << '\n';
        exit(1);
    }
    return res;
}

void show(int u, int fa) {
    cout << u << ' ';
    for (auto v : G[u]) {
        if (v == fa || !vld[v]) continue;
        show(v, u);
    }
}

int main() {
#ifdef TEST
    freopen("zz.in", "r+", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t; cin >> t;
    while (t --) {
        int n; cin >> n;
        for (int i = 1; i <= n; ++ i) {
            G[i].clear();
            vld[i] = 1;
        }

        for (int i = 1; i <= n; ++ i) {
            int l, r; cin >> l >> r;
            if (l) add_edge(i, l);
            if (r) add_edge(i, r);
        }

        int rt = 1;
        while (dfs(rt, 0) > 1) {
            int nrt = -1;
            center(rt, 0, 0, nrt);
            rt = nrt;

            dfs(rt, 0);

            // show(rt, 0);
            // cout << '\n';

            vector<int> vch;
            for (auto v : G[rt]) if (vld[v] && sz[v]) vch.emplace_back(v);
            sort(vch.begin(), vch.end(), [&](auto x, auto y) {
               return sz[x] > sz[y]; 
            });
            
            fg(rt, 0, 0);
            if (vch.size() >= 2) {
                int u = vch[0], v = vch[1];
                int x = query(u, v);
                if (x == 0) fg(u, rt, 1);
                if (x == 1) fg(rt, 0, 1), fg(u, rt, 0), fg(v, rt, 0);
                if (x == 2) fg(v, rt, 1);
            } else {
                assert(sz[rt] == 2);
                int u = vch[0];
                int x = query(u, rt);
                if (x == 0) fg(u, rt, 1);
                if (x == 1) assert(0);
                if (x == 2) fg(rt, 0, 1), fg(u, rt, 0);                
            }
    
            for (int i = 1; i <= n; ++ i) vld[i] &= f[i];
            for (int i = 1; i <= n; ++ i) if (vld[i]) rt = i;
        }

        cout << "! " << rt << '\n';
        cout.flush();
    }
}