#include <bits/stdc++.h>
using namespace std;
vector<int> p;
int init[100000], goal[100000], a = 0, b = 0;
vector<int> g[110000], ans;
void dfs(int v, int pr, int h) {
  if (h % 2 == 0) {
    if (a % 2 == 1) {
      init[v] = 1 - init[v];
    }
  } else {
    if (b % 2 == 1) {
      init[v] = 1 - init[v];
    }
  }
  if (init[v] != goal[v]) {
    ans.push_back(v);
    if (h % 2 == 0) {
      a++;
    } else
      b++;
  }
  for (auto to : g[v]) {
    if (to != pr) {
      dfs(to, v, h + 1);
    }
  }
  if (init[v] != goal[v]) {
    if (h % 2 == 0) {
      a++;
    } else
      b++;
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  for (int i = 1; i < n; ++i) {
    int a, b;
    cin >> a >> b;
    a--;
    b--;
    g[a].push_back(b);
    g[b].push_back(a);
  }
  for (int i = 0; i < n; ++i) {
    cin >> init[i];
  }
  for (int i = 0; i < n; ++i) {
    cin >> goal[i];
  }
  dfs(0, 0, 0);
  cout << ans.size() << '\n';
  for (auto to : ans) {
    cout << to + 1 << '\n';
  }
  return 0;
}
