#include <bits/stdc++.h>
using namespace std;
long long ok[200009], tt = 0;
long long nok[200009];
bool visit[200009];
vector<pair<long long, long long> > edge[200009];
vector<long long> vec;
queue<int> q;
void bfs(int x) {
  visit[x] = 1;
  q.push(x);
  while (!q.empty()) {
    int u = q.front();
    int si = edge[u].size();
    q.pop();
    for (int i = 0; i <= si - 1; i++) {
      int v = edge[u][i].first;
      int f = edge[u][i].second;
      if (visit[v] == 0) {
        visit[v] = 1;
        q.push(v);
        ok[v] = ok[u];
        nok[v] = nok[u];
        if (f == 1) {
          ok[v]++;
          tt++;
        } else
          nok[v]++;
      }
    }
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  long long n, u, v;
  cin >> n;
  for (int i = 1; i <= n - 1; i++) {
    cin >> u >> v;
    edge[u].push_back({v, 1});
    edge[v].push_back({u, 0});
  }
  bfs(1);
  long long ans = n - 1;
  for (int i = 1; i <= n; i++) {
    long long change = ok[i] - nok[i] + n - 1 - tt;
    if (change < ans) {
      vec.clear();
      vec.push_back(i);
      ans = change;
    } else if (change == ans) {
      vec.push_back(i);
    }
  }
  cout << ans << endl;
  sort(vec.begin(), vec.end());
  for (int i = 0; i <= vec.size() - 1; i++) cout << vec[i] << " ";
  cout << endl;
}
