#include <bits/stdc++.h>
using namespace std;
int n, pai[200010], ans[200010], T[200010], res;
vector<int> adj[200010], tipo[200010], dp[200010];
int go(int u) {
  T[u] = 0;
  for (int i = 0; i < adj[u].size(); i++) {
    int v = adj[u][i];
    if (v == pai[u]) continue;
    pai[v] = u;
    dp[u][i] = (go(v) + tipo[u][i]);
    T[u] += dp[u][i];
  }
  return T[u];
}
void solve(int u, int x) {
  ans[u] = T[u] + x;
  res = min(res, ans[u]);
  for (int i = 0; i < adj[u].size(); i++) {
    int v = adj[u][i];
    if (v == pai[u]) continue;
    pai[v] = u;
    solve(v, T[u] + x - dp[u][i] + 1 - tipo[u][i]);
  }
  return;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n - 1; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    u--;
    v--;
    adj[u].push_back(v);
    tipo[u].push_back(0);
    dp[u].push_back(0);
    adj[v].push_back(u);
    tipo[v].push_back(1);
    dp[v].push_back(0);
  }
  pai[0] = -1;
  go(0);
  pai[0] = -1;
  res = n;
  solve(0, 0);
  printf("%d\n", res);
  int first = 1;
  for (int i = 0; i < n; i++)
    if (ans[i] == res) {
      if (!first) printf(" ");
      first = 0;
      printf("%d", i + 1);
    }
  printf("\n");
  return 0;
}
