#include <bits/stdc++.h>

using namespace std;
using LL = long long;
using PII = pair<int , int>;

void solved() {
    int n;
    cin >> n;

    vector<vector<int>> g(n + 1);

    int nn = n;
    auto add = [&](int a , int b){
        g[a].push_back(b);
        g[b].push_back(a);
    };

    auto ask = [&](int u , int v){
        cout << "? " << u << " " << v << endl;
        cout.flush();

        int x;
        cin >> x;
        return x;
    };

    for(int i = 1 ; i <= n ; i ++ ){
        int x , y;
        cin >> x >> y;
        if(x) add(i , x);
        if(y) add(i , y);
    }

    auto find = [&](int x){
        vector<int> cnt(nn + 1) , sum(nn + 1) , st(nn + 1);
        int mx = 1e9 , k = 0;
        auto dfs = [&](auto f , int u) -> int {
            st[u] = true;

            for(int v : g[u]){
                if(st[v]) continue;
                int s = f(f , v);
                sum[u] += s;
                cnt[u] = max(cnt[u] , s);
            }

            cnt[u] = max(cnt[u] , n - sum[u] - 1);
            if(mx > cnt[u]){
                mx = cnt[u];
                k = u;
            }
            return sum[u] + 1;
        };

        dfs(dfs , x);

        return k;
    };

    int last = 1;
    while(1){
        if(n == 1){
            cout << "! " << last << endl;
            cout.flush();
            return ;
        }
        int x = find(last);

        cout << "! " << x << endl;
        cout.flush();
        return ;
//        cout << x << endl;
        if(g[x].size() == 0){
            cout << "! " << x << endl;
            cout.flush();
            return ;
        }

        if(g[x].size() == 1){
            int t = ask(x , g[x][0]);
            int ans;
            if(t == 0) ans = x;
            else ans = g[x][0];
            cout << "! " << ans << endl;
            cout.flush();
            return ;
        }

        if(g[x].size() == 2){
            cout << "! " << x << endl;
            cout.flush();
            return ;
            auto a = g[x];
            int t = ask(x , a[0]);
            g[x].clear();
            if(t == 0){
                last = a[1];
                g[a[1]].erase(std::find(g[a[1]].begin(), g[a[1]].end(),x));
            }else last = a[0] , g[a[0]].erase(std::find(g[a[0]].begin(), g[a[0]].end(),x));
        }

        if(g[x].size() == 3){
            cout << "! " << x << endl;
            cout.flush();
            return ;
//            auto a = g[x];
//            int t = ask(a[0] , a[1]);
//            g[x].clear();
//            if(t == 0) {
//                last = a[0];
//                g[a[0]].erase(std::find(g[a[0]].begin(), g[a[0]].end(),x));
//            }else if(t == 1){
//                last = a[2];
//                g[a[2]].erase(std::find(g[a[2]].begin(), g[a[2]].end(),x));
//            }else { last = a[1];
//                g[a[1]].erase(std::find(g[a[1]].begin(), g[a[1]].end(),x));
//            }
        }

        vector<int> st(nn + 1);
        n = 0;
        auto dfs = [&](auto f , int u) -> void{
            st[u] = true;
            n ++;

            for(int x : g[u]){
                if(st[x]) continue;
                f(f , x);
            }
        };

        dfs(dfs , last);

//        for(int i = 1 ; i <= nn ; i ++ )
//            for(int x : g[i])
//                cout << i << " " << x << endl;
    }

}

int main(){

    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t = 1;
    cin >> t;

    while(t -- )
        solved();

    return 0;
}