#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n;
  cin >> n;
  vector<long long> gr[n];
  vector<long long> ind(n, 0);
  for (int i = 0; i < n - 1; i++) {
    long long x, y;
    cin >> x >> y;
    x--;
    y--;
    gr[x].push_back(y);
    gr[y].push_back(x);
    ind[x]++;
    ind[y]++;
  }
  while (1) {
    vector<long long> arr;
    for (int i = 0; i < n; i++)
      if (ind[i] == 1) arr.push_back(i);
    long long a = arr[0], b = arr[1];
    cout.flush();
    cout << "? " << a + 1 << " " << b + 1 << "\n";
    long long c;
    cin >> c;
    c--;
    if (c == a || c == b) {
      cout.flush();
      cout << "! " << c + 1 << "\n";
      break;
    }
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < gr[i].size(); j++) {
        long long k = gr[i][j];
        if (k == a || k == b) ind[i]--;
      }
    }
    ind[a] = 0;
    ind[b] = 0;
    long long mx = 0;
    for (int i = 0; i < n; i++) mx = max(mx, ind[i]);
    if (mx == 0) {
      cout.flush();
      cout << "! " << c + 1 << "\n";
      break;
    }
  }
}
