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

#define int long long
#define MAXN 500005
#define pb push_back

int n,m;
set<int>v[MAXN];
int s[MAXN];
int c[MAXN],fa[MAXN];

int CNT = 0;
void dfs(int x,int ls) {
    s[x] = 1;
    CNT ++;
    if(CNT > n) exit(0);
    m ++;
    c[m] = x;
    for(auto y:v[x]) {
        if(y != ls) {
            fa[y] = x;
            dfs(y,x);
            s[x] += s[y];
        }
    }
}

signed main() {
    int T;
    cin >> T;
    
    while(T --) {
        for(int i = 0 ; i <= n; i ++) {
            v[i].clear();
            v[i].erase(v[i].begin(),v[i].end());
            s[i] = 0; c[i] = 0; fa[i] = 0;
        }
        cin >> n;
        int pp = 0;
        for(; (1<<pp) <= n; pp ++) ;
        for(int i = 1; i <= n; i ++) {
            int x,y;
            cin >> x >> y;
            if(x != 0) {
                v[i].insert(x);
                v[x].insert(i);
            } 
            if(y != 0) {
                v[i].insert(y);
                v[y].insert(i);
            }
        }
        cout<<"? 1 2\n";
        fflush(stdout);
        return 0;
        int o = 1;
        int cnt = 0;
        while(1) {
            if(o > n) return 0;
            m = 0;
            fa[o] = 0;
            CNT = 0;
            dfs(o,0);
            if(s[o] == 1) {
                cout<<"! "<<o<<"\n";
                cout.flush();
                break;
            }
            int ss = s[o];
            int t = 0,ux = 0,uy = 0;      
            
            for(int i = 1; i <= m; i ++) {
                int x = c[i],mx = 0;
                if(x > n) return 0;
                for(auto y:v[x]) {
                    if(y > n) return 0;
                    if(fa[y] == x) mx = max(mx,s[y]);
                    else {
                        mx = max(mx,ss-s[x]);
                    }
                }
                if(mx <= m/2) {
                    t = x;
                    //cout<<t<<" "<<mx<<" "<<ss<<"?\n";
                    if(v[x].size() == 1) {
                        ux = *v[x].begin();
                        uy = t;
                    } else {
                        int wp[5],nt = 0;
                        for(auto y:v[x]) {
                            int sy = 0;
                            if(fa[y] == x) sy = s[y];
                            else sy = ss-s[y];
                            nt ++;
                            wp[nt] = sy*1000000+y;
                        }
                        sort(wp+1,wp+nt+1);
                        ux = wp[nt]%1000000;
                        uy = wp[nt-1]%1000000;
                    }
                    break;
                }
            }
            if(t == 0 || t > n) return 0;
            if(ux > n) return 0;
            if(v[t].size() == 1) {
                cnt ++;
                if(cnt > pp) {
                    return 0;
                }
                cout<<"? "<<t<<" "<<ux<<"\n";
                cout.flush();
                int ans;
                cin >> ans;
                if(ans == 0) {
                    cout<<"! "<<t<<"\n";
            cout.flush();
                    break;
                }   else {
                    cout<<"! "<<ux<<"\n";
            cout.flush();
                    break;
                }
            }
            if(ux <= 0 || uy <= 0 || ux > n || uy > n) return 0;

            cnt ++;
            if(cnt > pp) {
                cout<<"wtf\n";
                return 0;
            }
            cout<<"? "<<ux<<" "<<uy<<"\n";
            cout.flush();
            int ans;
            cin >> ans;
            if(ans == 0) {
                v[ux].erase(t);
                o = ux;
            }
            if(ans == 2) {
                v[uy].erase(t);
                o = uy;
            }
            if(ans == 1) {
                v[t].erase(ux);
                v[t].erase(uy);
                o = t;
            }
        }
        //cout<<o<<"\n";
    }
    return 0;
}