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

using ll = long long;

void solve() {
    int n;
    cin >> n;
    vector G(n + 1, vector<int>());
    for(int i = 1; i <= n; i++) {
        int l, r;
        cin >> l >> r;
        if(l) G[l].push_back(i), G[i].push_back(l);
        if(r) G[r].push_back(i), G[i].push_back(r);
    }
    vector<int> vis(n + 1), sz(n + 1);
    int mn, p, num;
    auto dfs1 = [&](auto self, int x, int fz) -> void {
        num++;
        for(int y : G[x]) if(y != fz && !vis[y]) {
            self(self, y, x);
        }
    };
    auto dfs2 = [&](auto self, int x, int fz) -> void {
        int mx = 0;
        sz[x] = 1;
        for(int y : G[x]) if(y != fz && !vis[y]) {
            self(self, y, x);
            sz[x] += sz[y];
            mx = max(mx, sz[y]);
        }
        mx = max(mx, num - sz[x]);
        if(mx < mn) {
            mn = mx, p = x;
        }
    };
    auto getRt = [&](int x) {
        mn = 1e9, num = 0;
        dfs1(dfs1, x, -1);
        dfs2(dfs2, x, -1);
        dfs2(dfs2, p, -1);
        return p;
    };
    p = 1;
    while(1) {
        int rt = getRt(p);
        if(sz[rt] == 1) {
            cout << "! " << rt << endl;
            break;
        }
        auto query = [&](int x, int y) {
            cout << "? " << x << ' ' << y << endl;
            int res; cin >> res; return res;
        };
        if(G[rt].size() == 1) {
            int son = G[rt][0];
            int res = query(rt, son);
            if(res == 0) { // rt < son
                p = rt, vis[son] = 1;
            } else if(res == 2) { // son < rt
                p = son, vis[rt] = 1;
            } else {
                assert(false);
            }
        } else {
            assert(G[rt].size() <= 3);
            sort(G[rt].begin(), G[rt].end(), [&](int x, int y) { return sz[x] > sz[y]; });
            int son1 = G[rt][0], son2 = G[rt][1];
            int res = query(son1, son2);
            if(res == 0) { // son1 < son2
                p = son1, vis[rt] = 1;
            } else if(res == 1) { // son1 == son2
                p = rt, vis[son1] = vis[son2] = 1;
            } else { // son1 > son2
                p = son2, vis[rt] = 1;
            }
        }
    }
}
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    int t = 1;
    cin >> t;
    while(t--) solve();
    return 0;
}