#include <algorithm>
#include <cmath>
#include <cstring>
#include <iostream>
#include <vector>

const int N = 1e5;
int head[N + 2], nxt[N * 2 + 2], ver[N * 2 + 2], tot;
int n, v[N + 2], sz[N + 2], mx[N + 2], S, root;

void add(int x, int y) {
    tot++;
    nxt[tot] = head[x];
    ver[tot] = y;
    head[x] = tot;
}

void find(int x, int fa) {
    sz[x] = 1, mx[x] = 0;
    for (int i = head[x]; i; i = nxt[i]) {
        int y = ver[i];
        if (y == fa || v[y]) continue;
        find(y, x);
        sz[x] += sz[y];
        mx[x] = std::max(mx[x], sz[y]);
    }
    mx[x] = std::max(mx[x], S - sz[x]);
    if (mx[x] < mx[root]) root = x;
}

void deal(int x) {
    v[x] = 1;

    std::vector<int> q;
    for (int i = head[x]; i; i = nxt[i]) {
        int y = ver[i];
        if (v[y]) continue;
        q.push_back(y);
    }
    if (q.size() == 0) {
        std::cout << "! " << x << std::endl;
        std::cout.flush();
        return;
    } else if (q.size() == 1) {  // ?
        std::cout << "? "<<q[0] << " " << x << std::endl;
        std::cout.flush();
        int a;
        std::cin >> a;
        if (a == 0)
            std::cout << "! " << q[0] << std::endl;
        else
            std::cout << "! " << x << std::endl;
        std::cout.flush();
        return;
    } else {
        std::cout <<"? "<< q[0] << " " << q[1] << std::endl;
        std::cout.flush();
        int a;
        std::cin >> a;
        if (a == 1) {
            v[q[0]] = 1, v[q[1]] = 1, v[x] = 0;
            find(x, q[0]);
            S = sz[x], root = 0, mx[0] = 1e9;
            find(x, q[0]);
            deal(root);
        } else if (a == 0) {
            find(q[0], x);
            S = sz[q[0]], root = 0, mx[0] = 1e9;
            find(q[0], x);
            deal(root);
        } else {
            find(q[1], x);
            S = sz[q[1]], root = 0, mx[0] = 1e9;
            find(q[1], x);
            deal(root);
        }
    }
    std::cout.flush();
}

void solve() {
    std::cin >> n;
    tot = 0;
    for (int i = 1; i <= n + 1; i++) head[i] = v[i] = sz[i] = mx[i] = 0;
    for (int i = 1; i <= n; i++) {
        int a, b;
        std::cin >> a >> b;
        if (a) add(i, a), add(a, i);
        if (b) add(i, b), add(b, i);
    }
    // add(n, n + 1), add(n + 1, n);
    // root = n + 1;
    find(1, 0);
    S = sz[1], root = 0, mx[0] = 1e9;
    find(1, 0);
    deal(root);
}

int main() {
    int times;
    std::cin >> times;
    while (times--) {
        solve();
    }
    return 0;
}

/*
1
5
4 0
1 3
0 5
0 0
0 0

*/