#include <bits/stdc++.h>
using namespace std;
long long int tt;
vector<vector<long long int> > adj(200005, vector<long long int>());
vector<long long int> dp(200005, 0);
map<pair<long long int, long long int>, long long int> mp;
vector<long long int> ans;
long long int ans1;
long long int dfs(long long int x, long long int par) {
  for (long long int i = 0; i < adj[x].size(); i++) {
    if (adj[x][i] != par) {
      if (mp[{x, adj[x][i]}] == 0) {
        dp[x]++;
      }
      dp[x] += dfs(adj[x][i], x);
    }
  }
  return dp[x];
}
void dfs1(long long int x, long long int par, long long int s) {
  if (x == 1) {
    ans1 = dp[1];
    ans.push_back(x);
    for (long long int i = 0; i < adj[x].size(); i++) {
      long long int y;
      if (mp[{adj[x][i], x}] == 1) {
        y = -1;
      } else {
        y = 1;
      }
      dfs1(adj[x][i], x, s + dp[x] - dp[adj[x][i]] + y);
    }
  } else {
    long long int s1;
    s1 = s + dp[x];
    if (s1 < ans1) {
      ans1 = s1;
      ans.clear();
      ans.push_back(x);
    } else if (ans1 == s1) {
      ans.push_back(x);
    }
    for (long long int i = 0; i < adj[x].size(); i++) {
      if (adj[x][i] != par) {
        long long int y;
        if (mp[{adj[x][i], x}] == 1) {
          y = -1;
        } else {
          y = 1;
        }
        dfs1(adj[x][i], x, s + dp[x] - dp[adj[x][i]] + y);
      }
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long int n;
  cin >> n;
  for (long long int i = 1; i < n; i++) {
    long long int u, v;
    cin >> u >> v;
    adj[u].push_back(v);
    adj[v].push_back(u);
    mp[{u, v}]++;
  }
  dfs(1, -1);
  dfs1(1, -1, 0);
  cout << ans1 << endl;
  sort(ans.begin(), ans.end());
  for (long long int i = 0; i < ans.size(); i++) {
    cout << ans[i] << " ";
  }
  return 0;
}
