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

#define int long long
#define MAXN 200005
#define pb push_back

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

void dfs(int x,int ls) {
    s[x] = 1;
    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);
            }
        }
        int o = 1;
        int cnt = 0;
        while(1) {
            cnt ++;
            if(cnt > pp) {
                return 0;
            }
            m = 0;
            fa[o] = 0;
            dfs(o,0);
            if(s[o] == 1) {
                cout<<"! "<<o<<"\n";
                 fflush(stdout);
                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;
                for(auto y:v[x]) {
                    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) return 0;
            if(v[t].size() == 1) {
                cout<<"? "<<t<<" "<<ux<<"\n"; fflush(stdout);
                int ans;
                cin >> ans;
                if(ans == 0) {
                    cout<<"! "<<t<<"\n"; fflush(stdout);
                    break;
                }   else {
                    cout<<"! "<<ux<<"\n"; fflush(stdout);
                    break;
                }
            }
            if(ux <= 0 || uy <= 0 || ux > n || uy > n) return 0;
            cout<<"? "<<ux<<" "<<uy<<"\n"; fflush(stdout);
            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;
}

answer.code:1:1: error: ‘include’ does not name a type
    1 | include<bits/stdc++.h>
      | ^~~~~~~
answer.code:9:1: error: ‘set’ does not name a type
    9 | set<int>v[MAXN];
      | ^~~
answer.code: In function ‘void dfs(long long int, long long int)’:
answer.code:17:16: error: ‘v’ was not declared in this scope
   17 |     for(auto y:v[x]) {
      |                ^
answer.code: In function ‘int main()’:
answer.code:28:5: error: ‘cin’ was not declared in this scope
   28 |     cin >> T;
      |     ^~~
answer.code:31:13: error: ‘v’ was not declared in this scope
   31 |             v[i].clear();
      |             ^
answer.code:42:17: error: ‘v’ was not declared in this scope
   42 |                 v[i].insert(x);
      |                 ^
answer.code:46:17: error: ‘v’ was not declared in this scope
   46 |                 v[i].insert(y);
      |                 ^
answer.code:61:17: error: ‘cout’ was not declared in this scope
   61 |                 cout<<"! "<<o<<"\n";
      |                 ^~~~
answer.code:62:25: error: ‘stdout’ was not declared in this scope
   62 |                  fflush(stdout);
      |                         ^~~~~~
answer.code:1:1: note: ‘stdout’ is defined in header ‘<cstdio>’; did you forget to ‘#include <cstdio>’?
  +++ |+#include <cstdio>
    1 | include<bits/stdc++.h>
answer.code:62:18: error: ‘fflush’ was not declared in this scope
   62 |                  fflush(stdout);
      |                  ^~~~~~
answer.code:70:28: error: ‘v’ was not declared in this scope
   70 |                 for(auto y:v[x]) {
      |                            ^
answer.code:71:41: error: ‘max’ was not declared in this scope; did you mean ‘mx’?
   71 |                     if(fa[y] == x) mx = max(mx,s[y]);
      |                                         ^~~
      |                                         mx
answer.code:73:30: error: ‘max’ was not declared in this scope; did you mean ‘mx’?
   73 |                         mx = max(mx,ss-s[x]);
      |                              ^~~
      |                              mx
answer.code:79:24: error: ‘v’ was not declared in this scope
   79 |                     if(v[x].size() == 1) {
      |                        ^
answer.code:91:25: error: ‘sort’ was not declared in this scope; did you mean ‘short’?
   91 |                         sort(wp+1,wp+nt+1);
      |                         ^~~~
      |                         short
answer.code:99:16: error: ‘v’ was not declared in this scope
   99 |             if(v[t].size() == 1) {
      |                ^
answer.code:100:17: error: ‘cout’ was not declared in this scope
  100 |                 cout<<"? "<<t<<" "<<ux<<"\n"; fflush(stdout);
      |                 ^~~~
answer.code:100:54: error: ‘stdout’ was not declared in this scope
  100 |                 cout<<"? "<<t<<" "<<ux<<"\n"; fflush(stdout);
      |                                                      ^~~~~~
answer.code:100:54: note: ‘stdout’ is defined in header ‘<cstdio>’; did you forget to ‘#include <cstdio>’?
answer.code:100:47: error: ‘fflush’ was not declared in this scope
  100 |                 cout<<"? "<<t<<" "<<ux<<"\n"; fflush(stdout);
      |                                               ^~~~~~
answer.code:112:13: error: ‘cout’ was not declared in this scope
  112 |             cout<<"? "<<ux<<" "<<uy<<"\n"; fflush(stdout);
      |             ^~~~
answer.code:112:51: error: ‘stdout’ was not declared in this scope
  112 |             cout<<"? "<<ux<<" "<<uy<<"\n"; fflush(stdout);
      |                                                   ^~~~~~
answer.code:112:51: note: ‘stdout’ is defined in header ‘<cstdio>’; did you forget to ‘#include <cstdio>’?
answer.code:112:44: error: ‘fflush’ was not declared in this scope
  112 |             cout<<"? "<<ux<<" "<<uy<<"\n"; fflush(stdout);
      |                                            ^~~~~~
answer.code:116:17: error: ‘v’ was not declared in this scope
  116 |                 v[ux].erase(t);
      |                 ^
answer.code:120:17: error: ‘v’ was not declared in this scope
  120 |                 v[uy].erase(t);
      |                 ^
answer.code:124:17: error: ‘v’ was not declared in this scope
  124 |                 v[t].erase(ux);
      |                 ^