#include <bits/stdc++.h>

using namespace std;

#define int long long

int tot = 0;

int query(int u, int v) {
    tot--;
    assert(tot >= 0);
    std::cout << "? " << u << " " << v << std::endl;
    int x;
    std::cin >> x;
    return x;
}

void answer(int x) {
    std::cout << "! " << x << std::endl;
}

void solve() {
    int n;
    std::cin >> n;
    tot = std::__lg(n);
    std::vector<std::vector<int>> adj(n + 1);
    for (int i = 1; i <= n; i++) {
        int ls, rs;
        std::cin >> ls >> rs;
        if (ls) {
            adj[i].push_back(ls);
            adj[ls].push_back(i);
        }
        if (rs) {
            adj[i].push_back(rs);
            adj[rs].push_back(i);
        }
    }

    std::vector<int> vis(n + 1), sz(n + 1), f(n + 1);
    f[0] = 1E9;
    auto work = [&](auto self, int x, int SZ) -> void {
        if (SZ == 1) {
            answer(x);
            return;
        }
        auto p = 0;
        auto dfs = [&](auto self, int x, int fx) -> void {
            sz[x] = 1;
            f[x] = 0;
            for (auto y : adj[x]) {
                if (y == fx || vis[y] == 1) continue;
                self(self, y, x);
                sz[x] += sz[y];
                f[x] = std::max(f[x], sz[y]);
            }
            f[x] = std::max(f[x], SZ - sz[x]);
            if (f[x] < f[p]) {
                p = x;
            }

        };
        dfs(dfs, x, 0);
        dfs(dfs, p, 0);

        // std::cerr << "!!!" << p << std::endl;
        std::vector<int> vec;
        for (auto y : adj[p]) {
            if (vis[y] == 0) {
                vec.push_back(y);
            }
        }
        if (vec.size() == 1) {
            int a = p, b = vec[0];
            int v = query(a, b);
            if (v == 0) {
                answer(a);
            } else if (v == 2) {
                answer(b);
            } else {
                assert(0);
            }
        } else if (vec.size() == 2) {
            int a = vec[0], b = vec[1];
            int v = query(a, b);
            vis[p] = 1;
            if (v == 0) {
                self(self, a, sz[a]);
            } else if (v == 2) {
                self(self, b, sz[b]);
            } else {
                answer(p);
            }
        } else if (vec.size() == 3) {
            int a = vec[0], b = vec[1];
            int v = query(a, b);

            if (v == 0) {
                self(self, a, sz[a]);
            } else if (v == 2) {
                self(self, b, sz[b]);
            } else {
                vis[a] = vis[b] = 1;
                self(self, vec[2], sz[vec[2]] + 1);
            }
        }

    };
    work(work, 1, n);
}

signed main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);

    int t = 1;
    std::cin >> t;

    while (t --) {
        solve();
    }
}