#include <bits/stdc++.h>
using namespace std;
const long long INF = 1e18, MOD = 1e9 + 7, MAXN = 18, MAXM = 1e5 + 1;
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
vector<vector<pair<long long, long long>>> f;
vector<long long> ans, out;
void dfs(long long v, long long p = -1) {
  for (auto to : f[v]) {
    if (to.first != p) {
      dfs(to.first, v);
      out[v] += out[to.first] + to.second;
    }
  }
}
void dfs1(long long v, long long p, long long dir) {
  ans[v] = ans[p] + (dir ? -1 : 1);
  for (auto to : f[v]) {
    if (to.first != p) {
      dfs1(to.first, v, to.second);
    }
  }
}
signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  long long n, a, b;
  cin >> n;
  f.resize(n);
  out.resize(n);
  ans.resize(n);
  for (long long i = 0; i < n - 1; i++) {
    cin >> a >> b;
    a--, b--;
    f[a].push_back({b, 0});
    f[b].push_back({a, 1});
  }
  dfs(0);
  ans[0] = out[0];
  for (auto to : f[0]) {
    dfs1(to.first, 0, to.second);
  }
  long long mn = INF;
  for (long long i = 0; i < n; i++) {
    mn = min(mn, ans[i]);
  }
  cout << mn << '\n';
  for (long long i = 0; i < n; i++) {
    if (ans[i] == mn) cout << i + 1 << ' ';
  }
}
