#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  if (n == 1) {
    cout << "! 1" << endl;
    return 0;
  }
  vector<vector<int>> g(n);
  for (int i = 0; i < n - 1; ++i) {
    int u, v;
    cin >> u >> v;
    --u;
    --v;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  vector<int> imp(n, false);
  int q = n / 2;
  srand(time(NULL));
  while (q--) {
    vector<int> pos;
    for (int i = 0; i < n; ++i) {
      if (!imp[i]) pos.push_back(i);
    }
    if (pos.size() <= 1) break;
    sort(pos.begin(), pos.end(),
         [&g](int x, int y) { return g[x].size() < g[y].size(); });
    int u = pos[0], v = pos[1];
    cout << "? " << u + 1 << ' ' << v + 1 << endl;
    int w;
    cin >> w;
    --w;
    function<bool(int, int)> dfs = [&](int x, int p) {
      if (x == u || x == v) return true;
      bool res = false;
      for (int y : g[x]) {
        if (y != p) {
          res |= dfs(y, x);
        }
      }
      return res;
    };
    function<void(int, int)> dfs2 = [&](int x, int p) {
      imp[x] = true;
      for (int y : g[x]) {
        if (y != p) {
          dfs2(y, x);
        }
      }
    };
    for (int x : g[w]) {
      if (dfs(x, w)) {
        dfs2(x, w);
      }
    }
  }
  for (int i = 0; i < n; ++i) {
    if (!imp[i]) {
      cout << "! " << i + 1 << endl;
      return 0;
    }
  }
  assert(false);
}
