#include <bits/stdc++.h>
using namespace std;
int n, a, b, mn, down, up, A[200005], B[200005];
vector<vector<int>> in, out;
vector<int> mother;
bitset<200005> visited;
void dfs(int u, int edge, int outs) {
  visited[u] = 1;
  A[u] = outs;
  B[u] = edge;
  bool leaf = 1;
  for (int i = 0; i < out[u].size(); i++) {
    int v = out[u][i];
    if (!visited[v]) {
      dfs(v, edge + 1, outs + 1);
      leaf = 0;
      down++;
    }
  }
  for (int i = 0; i < in[u].size(); i++) {
    int v = in[u][i];
    if (!visited[v]) {
      dfs(v, edge + 1, outs);
      leaf = 0;
      up++;
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  in.resize(n + 1);
  out.resize(n + 1);
  for (int i = 0; i < n - 1; i++) {
    cin >> a >> b;
    out[a].push_back(b);
    in[b].push_back(a);
  }
  dfs(1, 0, 0);
  mn = 1e9;
  for (int u = 1; u <= n; u++) {
    int cur = A[u] + up - (B[u] - A[u]);
    if (cur <= mn) {
      if (cur < mn) {
        mother.clear();
        mn = cur;
      }
      mother.push_back(u);
    }
  }
  cout << mn << '\n';
  for (int i = 0; i < mother.size(); i++) {
    if (i) {
      cout << " ";
    }
    cout << mother[i];
  }
  cout << '\n';
  return 0;
}
