#include <bits/stdc++.h>
using namespace std;
const int INF = numeric_limits<int>::max();
const long long LLINF = numeric_limits<long long>::max();
const unsigned long long ULLINF = numeric_limits<unsigned long long>::max();
vector<bool> goal, state;
vector<vector<int> > g;
vector<int> ans;
void dfs(int v, int p, int depth, bool chEven, bool chOdd) {
  if (depth % 2) {
    if (chOdd) state[v] = state[v] ^ 1;
    if (state[v] != goal[v]) {
      state[v] = state[v] ^ 1, chOdd = chOdd ^ 1;
      ans.push_back(v);
    }
  } else {
    if (chEven) state[v] = state[v] ^ 1;
    if (state[v] != goal[v]) {
      state[v] = state[v] ^ 1, chEven = chEven ^ 1;
      ans.push_back(v);
    }
  }
  for (int to : g[v])
    if (to != p) dfs(to, v, depth + 1, chEven, chOdd);
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  state.resize(n);
  goal.resize(n);
  g.resize(n);
  for (int i = 0; i < n - 1; 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++) {
    int a;
    cin >> a;
    state[i] = a;
  }
  for (int i = 0; i < n; i++) {
    int a;
    cin >> a;
    goal[i] = a;
  }
  dfs(0, -1, 0, 0, 0);
  cout << ans.size() << '\n';
  for (int i : ans) cout << i + 1 << '\n';
  return 0;
}
