#include<bits/stdc++.h>
#define se second
using namespace std;
const int N = 1e5;
int n;
int del[N];
int root;
vector<int> e[N];
vector<int> V;
int siz[N], mxs[N];
void dfs(int u, int p) {
    V.push_back(u);
    siz[u] = 1;
    mxs[u] = 0;
    for (int v : e[u]) if (v != p && !del[v])
        dfs(v, u), mxs[u] = max(mxs[u], siz[v]), siz[u] += siz[v];
}
void Del(int u, int p) {
    del[u] = 1;
    for (int v : e[u]) if (v != p && !del[v])
        Del(v, u);
}

void solve() {
    cin >> n;
    for(int i = 1;i <= n;++i) e[i].clear(), del[i] = 0;
    for(int i = 1;i <= n;++i){
        int x, y; cin >> x >> y;
        if (x) e[i].push_back(x), e[x].push_back(i);
        if (y) e[i].push_back(y), e[y].push_back(i);
    }
    root = 1;
    while (true) {
        V.clear();
        dfs(root, 0);
        int tot = (int)V.size();
        root = 0;
        for (int u : V) {
            mxs[u] = max(mxs[u], tot - siz[u]);
            if (!root || mxs[root] > mxs[u])
                root = u;
        }
        V.clear();
        dfs(root, 0);
        if (tot == 1) {
            cout << "! " << root << endl;
            return ;
        }
        vector<pair<int, int>> w;
        for (int v : e[root]) if (!del[v])
            w.push_back({siz[v], v});
        sort(w.begin(), w.end());
        reverse(w.begin(), w.end());
        int deg = (int)w.size();
        if (deg == 1) {
            cout << "? " << root << ' ' << w[0].se << endl;
            int t; cin >> t;
            if (t == 0) del[w[0].se] = 1;
            else del[root] = 1, root = w[0].se;
        } else if (deg == 2) {
            cout << "? " << w[0].se << ' ' << w[1].se << endl;
            int t; cin >> t;
            if (t == 0) Del(root, w[0].se), root = w[0].se;
            else if (t == 1) Del(w[0].se, root), Del(w[1].se, root);
            else Del(root, w[1].se), root = w[1].se;
        } else {
            cout << "? " << w[0].se << ' ' << w[1].se << endl;
            int t; cin >> t;
            if (t == 0) Del(root, w[0].se), root = w[0].se;
            else if (t == 1) Del(w[0].se, root), Del(w[1].se, root);
            else Del(root, w[1].se), root = w[1].se;
        }
    }
}
int main() {
    // ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int t = 1;
    cin >> t;
    while(t--){
        solve();
    }
    return 0;
}