#include <bits/stdc++.h>
using namespace std;
pair<int, int> add(pair<int, int> p1, pair<int, int> p2, int odd, int even) {
  return make_pair(p1.first + p2.first - odd, p1.second + p2.second - even);
}
pair<int, int> dfs(vector<int>* adj, int* visited, int* store, int u,
                   int parent, int odd, int even, int* l, int* m,
                   vector<int>& v) {
  visited[u] = 1;
  int level = store[u];
  if (level % 2 == 1) {
    if (l[u] != m[u] ^ odd % 2 == 1) {
      odd++;
      v.push_back(u);
    }
  } else {
    if (l[u] != m[u] ^ even % 2 == 1) {
      even++;
      v.push_back(u);
    }
  }
  pair<int, int> p = make_pair(odd, even);
  int a = p.first, b = p.second;
  for (int i = 0; i < adj[u].size(); i++) {
    if (adj[u][i] != parent && !visited[adj[u][i]])
      p = add(p, dfs(adj, visited, store, adj[u][i], u, a, b, l, m, v), a, b);
  }
  return p;
}
int main() {
  int n;
  scanf("%d", &n);
  ;
  vector<int>* adj = new vector<int>[n];
  for (int i = 0; i < n - 1; i++) {
    int a, b;
    scanf("%d", &a);
    ;
    scanf("%d", &b);
    ;
    a--;
    b--;
    adj[a].push_back(b);
    adj[b].push_back(a);
  }
  int l[n], m[n];
  for (int i = 0; i < n; i++) scanf("%d", &l[i]);
  ;
  for (int i = 0; i < n; i++) scanf("%d", &m[i]);
  ;
  int* visited = (int*)calloc(n, sizeof(int));
  int* store = (int*)calloc(n, sizeof(int));
  queue<int> q;
  int even = 0, odd = 0, level = 1;
  q.push(0);
  q.push(-1);
  visited[0] = 1;
  while (!q.empty()) {
    int u = q.front();
    q.pop();
    if (u == -1 && !q.empty()) {
      level++;
      q.push(-1);
      continue;
    } else if (u == -1)
      break;
    visited[u] = 1;
    store[u] = level;
    for (int i = 0; i < adj[u].size(); i++) {
      if (!visited[adj[u][i]]) {
        q.push(adj[u][i]);
        visited[adj[u][i]] = 1;
      }
    }
  }
  for (int i = 0; i < n; i++) visited[i] = 0;
  vector<int> v;
  pair<int, int> p = dfs(adj, visited, store, 0, -1, 0, 0, l, m, v);
  cout << p.first + p.second << endl;
  for (int i = 0; i < v.size(); i++) cout << v[i] + 1 << endl;
  return 0;
}
