#include <bits/stdc++.h>
using namespace std;
const int N = 2 * 1e5 + 7;
vector<pair<int, int> > V[N];
int F[N], G[N];
bool b[N];
void dfs(int u) {
  b[u] = false;
  for (int i = 0; i < V[u].size(); i++) {
    int v = V[u][i].first;
    int t = V[u][i].second;
    if (b[v]) {
      dfs(v);
      if (t == 1)
        F[u] = F[u] + F[v] + 1;
      else
        F[u] = F[u] + F[v];
    }
  }
}
void dfss(int u) {
  b[u] = false;
  for (int i = 0; i < V[u].size(); i++) {
    int v = V[u][i].first;
    int t = V[u][i].second;
    if (b[v]) {
      if (t == 0)
        G[v] = G[u] + 1;
      else
        G[v] = G[u] - 1;
      dfss(v);
    }
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  for (int i = 1; i < n; i++) {
    int u, v;
    cin >> u >> v;
    V[u].push_back(make_pair(v, 0));
    V[v].push_back(make_pair(u, 1));
  }
  memset(b, true, sizeof(b));
  memset(F, 0, sizeof(F));
  memset(G, 0, sizeof(G));
  dfs(1);
  G[1] = F[1];
  memset(b, true, sizeof(b));
  dfss(1);
  int res = N;
  for (int i = 1; i <= n; i++) res = min(res, G[i]);
  cout << res << endl;
  for (int i = 1; i <= n; i++)
    if (res == G[i]) cout << i << " ";
  return 0;
}
