#include <bits/stdc++.h>
using namespace std;
constexpr int maxn = 2e5 + 5, inf = 0x3f3f3f3f;
int n, m, k, t, cnt, f[maxn];
struct edge {
  int v, w;
};
vector<edge> e[maxn];
int dfs(int u, int fa) {
  int ans = 0;
  for (auto x : e[u]) {
    int v = x.v;
    int w = x.w;
    if (v == fa) continue;
    if (!w) ans++;
    ans += dfs(v, u);
  }
  return ans;
}
void dfs2(int u, int fa) {
  cnt = min(f[u], cnt);
  for (auto x : e[u]) {
    int v = x.v;
    int w = x.w;
    if (v == fa) continue;
    f[v] = f[u] + (w == 1 ? 1 : -1);
    dfs2(v, u);
  }
}
int main() {
  cin >> n;
  cnt = inf;
  for (int i = 1; i <= n - 1; i++) {
    int u, v;
    cin >> u >> v;
    e[u].push_back((edge){v, 1});
    e[v].push_back((edge){u, 0});
  }
  f[1] = dfs(1, 0);
  dfs2(1, 0);
  cout << cnt << endl;
  for (int i = 1; i <= n; i++) {
    if (f[i] == cnt) {
      printf("%d ", i);
    }
  }
  return 0;
}
