#include <bits/stdc++.h>
using namespace std;
const int maxn = 3e5 + 10;
const int mod = 1e9 + 7;
vector<pair<int, int>> G[maxn];
int ans = 0;
int dp[maxn];
void dfs(int x, int fa) {
  for (int i = 0; i < G[x].size(); i++) {
    int to = G[x][i].first;
    if (to == fa) continue;
    ans += G[x][i].second;
    dfs(to, x);
  }
}
void dfs2(int x, int fa) {
  for (int i = 0; i < G[x].size(); i++) {
    int to = G[x][i].first;
    if (to == fa) continue;
    if (G[x][i].second == 1) {
      dp[to] = dp[x] - 1;
    } else {
      dp[to] = dp[x] + 1;
    }
    dfs2(to, x);
  }
}
vector<int> vec;
int main() {
  int n;
  cin >> n;
  for (int i = 1; i < n; i++) {
    int u, v;
    cin >> u >> v;
    G[u].push_back({v, 0});
    G[v].push_back({u, 1});
  }
  dfs(1, 0);
  dp[1] = ans;
  dfs2(1, 0);
  int mx = 0x3f3f3f3f;
  for (int i = 1; i <= n; i++) {
    mx = min(dp[i], mx);
  }
  for (int i = 1; i <= n; i++) {
    if (mx == dp[i]) vec.push_back(i);
  }
  cout << mx << endl;
  for (int i = 0; i < vec.size(); i++) cout << vec[i] << " ";
}
