#include <bits/stdc++.h>
using namespace std;
template <typename Arg1>
void __f(const char* name, Arg1&& arg1) {
  std::cerr << name << " : " << arg1 << endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args) {
  const char* comma = strchr(names + 1, ',');
  std::cerr.write(names, comma - names) << " : " << arg1 << " | ";
  __f(comma + 1, args...);
}
std::vector<pair<long long int, long long int>> adj[200010];
bool visited[200010];
long long int poss_ans[200010];
long long int dfs(long long int num) {
  visited[num] = true;
  long long int sum = 0;
  for (long long int i = 0; i < (long long int)adj[num].size(); i++) {
    long long int z = adj[num][i].first;
    long long int edge = adj[num][i].second;
    if (!visited[z]) {
      if (edge == 0) {
        sum++;
      }
      sum += dfs(z);
    }
  }
  return sum;
}
long long int dfs_calc(long long int num) {
  visited[num] = true;
  for (long long int i = 0; i < (long long int)adj[num].size(); i++) {
    long long int z = adj[num][i].first;
    long long int edge = adj[num][i].second;
    if (!visited[z]) {
      if (edge == 0) {
        poss_ans[z] = poss_ans[num] - 1;
        dfs_calc(z);
      } else {
        poss_ans[z] = poss_ans[num] + 1;
        dfs_calc(z);
      }
    }
  }
  return 0;
}
long long int solve() {
  long long int n;
  cin >> n;
  for (long long int i = 0; i < n - 1; i++) {
    long long int a, b;
    cin >> a >> b;
    adj[a].push_back(make_pair(b, 1));
    adj[b].push_back(make_pair(a, 0));
  }
  for (long long int i = 0; i < n + 1; i++) {
    visited[i] = false;
  }
  poss_ans[1] = dfs(1);
  for (long long int i = 0; i < n + 1; i++) {
    visited[i] = false;
  }
  dfs_calc(1);
  long long int ans = 1000000007;
  for (long long int i = 1; i <= n; i++) {
    ans = min(ans, poss_ans[i]);
  }
  std::vector<long long int> fin_ans;
  for (long long int i = 1; i < n + 1; i++) {
    if (poss_ans[i] == ans) {
      fin_ans.push_back(i);
    }
  }
  cout << ans << "\n";
  for (long long int i = 0; i < fin_ans.size(); i++) {
    cout << fin_ans[i] << " ";
  }
  cout << "\n";
  ;
  return 0;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long int T = 1;
  while (T--) {
    solve();
  }
  return 0;
}
