#include <bits/stdc++.h>
void err() { std::cout << '\n'; }
template <typename T, typename... Args>
void err(T a, Args... args) {
  std::cout << a << ' ';
  err(args...);
}
template <template <typename...> class T, typename t, typename... A>
void err(const T<t> &arg, const A &...args) {
  for (auto &v : arg) std::cout << v << ' ';
  err(args...);
}
using namespace std;
const int N = 1000 + 5;
int n;
vector<int> G[N], sons[N];
bool chk[N];
int now;
void dfs(int u, int fa) {
  for (auto v : G[u])
    if (v != fa) {
      dfs(v, u);
      sons[u].push_back(v);
    }
}
int query(int u, int v) {
  cout << '?' << ' ' << u << ' ' << v << endl;
  int z;
  cin >> z;
  return z;
}
int get(int u) {
  chk[u] = true;
  int SZ = (int)(sons[u]).size();
  for (auto it : sons[u])
    if (chk[it]) --SZ;
  if (SZ == 0) return u;
  for (auto it : sons[u])
    if (!chk[it]) {
      return get(it);
    }
}
void gao(int u) {
  now = u;
  int SZ = (int)(sons[u]).size();
  for (auto it : sons[u])
    if (chk[it]) --SZ;
  if (SZ == 0) {
    return;
  } else if (SZ == 1) {
    for (auto it : sons[u])
      if (!chk[it]) {
        int to = get(it);
        int z = query(u, to);
        now = z;
        if (z == to || z == u) return;
        gao(now);
        return;
      }
  } else {
    vector<int> v;
    for (auto it : sons[u])
      if (!chk[it]) v.push_back(it);
    for (int i = 0; i < (int)(v).size(); i += 2) {
      if (i + 1 < (int)(v).size()) {
        int z = query(v[i], v[i + 1]);
        if (z == v[i] || z == v[i + 1]) {
          now = z;
          gao(now);
          return;
        }
      } else {
        int to = get(v[i]);
        int z = query(u, to);
        now = z;
        if (z == to || z == u) return;
        gao(now);
        return;
      }
    }
  }
}
void run() {
  cin >> n;
  for (int i = 1; i < n; i++) {
    int u, v;
    cin >> u >> v;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  dfs(1, 0);
  gao(1);
  cout << "!" << ' ' << now << '\n';
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cout << fixed << setprecision(20);
  run();
  return 0;
}
