#include <bits/stdc++.h>
using namespace std;
int init[100005], goal[100005];
vector<int> g[100005], ans;
void dfs(int v, int p, int odd, int even, int h) {
  if (h % 2 == 1) {
    if (odd == 1) init[v] = 1 - init[v];
    if (init[v] != goal[v]) ans.push_back(v), odd = 1 - odd;
  } else {
    if (even == 1) init[v] = 1 - init[v];
    if (init[v] != goal[v]) ans.push_back(v), even = 1 - even;
  }
  for (int i = 0; i < g[v].size(); i++)
    if (g[v][i] != p) dfs(g[v][i], v, odd, even, h + 1);
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int i, n;
  cin >> n;
  for (i = 1; i <= n - 1; i++) {
    int a, b;
    cin >> a >> b;
    g[a].push_back(b);
    g[b].push_back(a);
  }
  for (i = 1; i <= n; i++) cin >> init[i];
  for (i = 1; i <= n; i++) cin >> goal[i];
  dfs(1, 0, 0, 0, 1);
  cout << ans.size() << '\n';
  for (int kk = 0; kk < ans.size(); kk++) cout << ans[kk] << '\n';
}
