#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, a, b) for(ll i = a; i < b; i++)


void solve(){
    int n;
    cin >> n;
    vector<vector<int>> g(n);
    rep(i, 0, n){
        int a,b;
        cin >> a >> b;
        a--,b--;
        if(a != -1){
            g[i].emplace_back(a);
            g[a].emplace_back(i);
        }
        if(b != -1){
            g[i].emplace_back(b);
            g[b].emplace_back(i);
        }
    }

    vector<int> none(n, 0);
    int ex = n;

    auto deldfs = [&](auto self, int nw, int p)-> void {
        ex--;
        none[nw] = 1;
        for(auto to: g[nw]){
            if(to == p) continue;
            self(self, to, nw);
        }
    };

    while(ex > 1){
        if(ex == 2){
            vector<int> d;
            rep(i,0,n) if(none[i] == 0) d.push_back(i);
            assert(ex == 2);
            cout << "? " << d[0] + 1 << " " << d[1] + 1 << endl;
            int ch;
            cin >> ch;
            if(ch == 0){
                none[d[1]] = 1;
            }else{
                none[d[0]] = 1;
            }
            break;
        }
        priority_queue<pair<int,int>> q;
        vector<int> out(n, 0);
        vector<int> v(n, 1);
        rep(i, 0, n){
            if(none[i]) out[i] = 0;
            else{
                int cnt = 0;
                for(auto to: g[i]){
                    if(none[to]) continue;
                    cnt++;
                }
                if(cnt == 1) q.push({-1, i});
                else out[i] = cnt;
            }
        }

        while(q.size()){
            auto [_v, nw] = q.top();
            q.pop();
            for(auto to: g[nw]){
                if(none[to]) continue;
                out[to]--;
                if(out[to] < 0) continue;
                v[to] += v[nw];

                if(out[to] == 0){
                    q.push({-v[to], to});
                }
            }
        }

        int mx = 0;
        int mid = -1;
        rep(i,0,n){
            if(none[i]) continue;
            if(mx < v[i]) {
                mx = v[i];
                mid = i;
            }
        }

        int U =-1,V =-1;
        for(auto to: g[mid]){
            if(U == -1) U = to;
            else if(V == -1) V = to;
            else{
                if(v[U] <= v[V] && v[U] < v[to]) U = to;
                else if(v[V] <= v[U] && v[V] < v[to]) V = to;
            }
        }
        cout << "? " << U + 1 << " " << V + 1 << endl;
        int ch;
        cin >> ch;
        if(ch == 0){
            deldfs(deldfs, mid, U);
        }
        if(ch == 1){
            deldfs(deldfs, U, mid);
            deldfs(deldfs, V, mid);
        }
        if(ch == 2){
            deldfs(deldfs, mid, V);
        }
    }

    int ls = 0;
    rep(i,0,n) if(none[i] == 0) ls = i+1;
    cout << "! " << ls << endl;
}

int main(){
    int t;
    cin >> t;
    while(t--){
        solve();
    }
}