#include <bits/stdc++.h>
const int MAXN = 200000 + 10;
struct EdgeType {
  int to, type;
};
std::vector<EdgeType> G[MAXN];
int dp[MAXN], dir[MAXN];
void dfs(int u, int p) {
  dp[u] = 0;
  for (int i = 0; i < G[u].size(); i++) {
    int v = G[u][i].to;
    if (v == p) continue;
    dir[v] = G[u][i].type;
    dfs(v, u);
    dp[u] += dp[v] + dir[v];
  }
}
void solve(int u, int p) {
  for (int i = 0; i < G[u].size(); i++) {
    int v = G[u][i].to;
    if (v == p) continue;
    dp[v] = dp[u] + (dir[v] ? -1 : 1);
    solve(v, u);
  }
}
int main() {
  int n;
  scanf("%d", &n);
  for (int i = 1; i < n; i++) {
    int u, v;
    scanf("%d%d", &u, &v);
    G[u].push_back((EdgeType){v, 0});
    G[v].push_back((EdgeType){u, 1});
  }
  dfs(1, -1);
  solve(1, -1);
  int ans = 0x3f3f3f3f;
  std::vector<int> result;
  for (int i = 1; i <= n; i++) {
    if (dp[i] < ans) {
      ans = dp[i];
      result.clear();
      result.push_back(i);
    } else if (dp[i] == ans)
      result.push_back(i);
  }
  printf("%d\n", ans);
  for (int i = 0; i < result.size(); i++) printf("%d ", result[i]);
}
