#include <bits/stdc++.h>
using namespace std;
int ans = 0;
vector<int> ver(0);
vector<int> used(100001);
vector<int> goal(100001);
vector<int> init(100001);
vector<vector<int>> gr(100001);
void dfs(int i, int odd, int even, int n) {
  if (n % 2) {
    if (odd % 2) {
      init[i] ^= 1;
    }
    if (goal[i] != init[i]) {
      ++ans;
      ver.push_back(i + 1);
      ++odd;
    }
  } else {
    if (even % 2) {
      init[i] ^= 1;
    }
    if (goal[i] != init[i]) {
      ++ans;
      ver.push_back(i + 1);
      ++even;
    }
  }
  for (int j = 0; j < gr[i].size(); ++j) {
    if (used[gr[i][j]] == 0) {
      used[gr[i][j]] = 1;
      dfs(gr[i][j], odd, even, n + 1);
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int n, a, b;
  cin >> n;
  for (int i = 0; i < n - 1; ++i) {
    cin >> a >> b;
    --a;
    --b;
    gr[a].push_back(b);
    gr[b].push_back(a);
  }
  for (int i = 0; i < n; ++i) {
    cin >> init[i];
  }
  for (int i = 0; i < n; ++i) {
    cin >> goal[i];
  }
  used[0] = 1;
  dfs(0, 0, 0, 0);
  cout << ans << '\n';
  for (int i = 0; i < ans; ++i) cout << ver[i] << '\n';
  return 0;
}
