/* -*- coding: utf-8 -*-
 *
 * 3237.cc:  No.3237 Find the Treasure! - yukicoder
 */

#include<cstdio>
#include<vector>
#include<algorithm>
#include<utility>

using namespace std;

/* constant */

const int MAX_N = 10000;

/* typedef */

using vi = vector<int>;
using pii = pair<int,int>;

/* global variables */

vi nbrs[MAX_N];
pii es[MAX_N];
int ps[MAX_N], cis[MAX_N], ds[MAX_N];
int xs[MAX_N];
bool used[MAX_N];

/* subroutines */

bool query(int m, int xs[]) {
  putchar('?');
  for (int i = 0; i < m; i++) printf(" %d", xs[i] + 1);
  putchar('\n'); fflush(stdout);

  char s[16];
  scanf("%s", s);
  if (s[0] == 'I') exit(0);
  return (s[0] == 'Y');
}

void answer(int t) {
  printf("! %d\n", t + 1); fflush(stdout);
}

/* main */

int main() {
  int n;
  scanf("%d", &n);
  int m = n - 1;
  for (int i = 0; i < m; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--, v--;
    nbrs[u].push_back(v);
    nbrs[v].push_back(u);
    es[i] = {u, v};
  }

  ps[0] = -1, ds[0] = 0;
  vi gvs[2];
  gvs[0].push_back(0);
  
  for (int u = 0; u >= 0;) {
    auto &nbru = nbrs[u];
    int up = ps[u];

    if (cis[u] < nbru.size()) {
      int v = nbru[cis[u]++];
      if (v != up) {
	ps[v] = u, ds[v] = ds[u] ^ 1;
	gvs[ds[v]].push_back(v);
	u = v;
      }
    }
    else {
      u = up;
    }
  }

  for (int i = 0; i < m; i++) {
    auto [u, v] = es[i];
    xs[i] = (! ds[u]) ? u : v;
  }
  int gid = query(m, xs) ? 0 : 1;
  auto &gv = gvs[gid];
  int k = gv.size();
  for (int i = 0; i < m; i++) {
    auto &[u, v] = es[i];
    if (ds[u] != gid) swap(u, v);
  }

  int bits = 0;
  for (int bi = 1; bi < k; bi <<= 1) {
    fill(used, used + n, false);
    for (int i = 0; i < k; i++)
      if (i & bi) used[gv[i]] = true;

    for (int i = 0; i < m; i++) {
      auto [u, v] = es[i];
      xs[i] = used[u] ? u : v;
    }
    if (query(m, xs)) bits |= bi;
  }

  answer(gv[bits]);

  //for (int i = 0; i < 1e9; i++);
  return 0;
}