#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define f(x) for(ll i = 1; i <= x; i ++)





void solve(){
    ll n;
    cin >> n;
    vector<ll> edge[n + 1];
    vector<ll> ind(n + 1);
    f(n){
        ll u, v;
        cin >> u >> v;
        if(u != 0)
            edge[i].push_back(u);
        if(v != 0)
            edge[i].push_back(v);
        ind[u]++;
        ind[v]++;
    }

    f(n){
        if(ind[i] == 0){
            ll x = i ;
            while(1){
                if(edge[x].size() == 0) {
                    cout << "! " << x << endl;
                    return ;
                }
                if(edge[x].size() == 1){
                    cout << "? " << edge[x][0] << ' ' << x << endl;
                    ll q;
                    cin >> q;
                    if(q == 0){
                        x = edge[x][0];
                    }
                    else {
                        cout << "! " << x << endl;
                        return ;
                    }
                }
                else {
                    cout << "? " << edge[x][0] << ' ' << edge[x][1] << endl;
                    ll q;
                    cin >> q;
                    if(q == 0){
                        x = edge[x][0];
                    }
                    else if(q == 1){
                        cout << "! " << x << endl;
                        return ;
                    }
                    else {
                        x = edge[x][1];
                    }
                }
            }
        }
    }

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

//nanjingnanjing

//4 1  15 -> n 2