#include <bits/stdc++.h>
using namespace std;
const int maxn = 200010;
int head[maxn];
struct Node {
  int to, next;
  int value;
};
Node edge[maxn * 2];
int tot;
int dp[maxn];
int ans[maxn];
int path;
void init() {
  path = 0;
  memset(dp, 0, sizeof(dp));
  memset(head, -1, sizeof(head));
  tot = 0;
}
void addedge(int u, int v, int value) {
  edge[tot].to = v;
  edge[tot].next = head[u];
  edge[tot].value = value;
  head[u] = tot++;
}
void dfs1(int u, int pre) {
  for (int i = head[u]; i != -1; i = edge[i].next) {
    int v = edge[i].to;
    if (v != pre) {
      path += edge[i].value;
      dfs1(v, u);
    }
  }
}
void dfs2(int u, int pre) {
  for (int i = head[u]; i != -1; i = edge[i].next) {
    int v = edge[i].to;
    if (v != pre) {
      if (edge[i].value == 0)
        dp[v] = dp[u] + 1;
      else
        dp[v] = dp[u] - 1;
      dfs2(v, u);
    }
  }
}
int main() {
  int n;
  scanf("%d", &n);
  int a, b;
  init();
  for (int i = 1; i < n; i++) {
    scanf("%d %d", &a, &b);
    addedge(a, b, 0);
    addedge(b, a, 1);
  }
  dfs1(1, 0);
  dp[1] = path;
  dfs2(1, 0);
  int min_value = 9999999, k;
  for (int i = 1; i <= n; i++) {
    if (min_value > dp[i]) {
      min_value = dp[i];
      k = i;
    }
  }
  printf("%d\n", min_value);
  for (int i = 1; i <= n; i++)
    if (min_value == dp[i]) printf("%d ", i);
  puts("");
  return 0;
}
