#include <bits/stdc++.h>
using namespace std;
vector<int> adjList[100005], goal, ini, ans, isVisited;
void DFS(int x, bool odd, bool even, int status) {
  if (!isVisited[x]) {
    isVisited[x] = 1;
    if (((status & 1) && odd) || (!(status & 1) && even))
      ini[x - 1] = !ini[x - 1];
    if (ini[x - 1] != goal[x - 1]) {
      ans.push_back(x);
      status& 1 ? odd = !odd : even = !even;
    }
    for (auto child : adjList[x]) DFS(child, odd, even, status + 1);
  }
}
int main(void) {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cerr.tie(NULL);
  ;
  int n, u, v;
  cin >> n;
  isVisited.assign(n + 1, 0);
  for (int i = 1; i < n; i++) {
    cin >> u >> v;
    adjList[u].push_back(v);
    adjList[v].push_back(u);
  }
  for (int i = 0; i < n; i++) {
    cin >> u;
    ini.push_back(u);
  }
  for (int i = 0; i < n; i++) {
    cin >> u;
    goal.push_back(u);
  }
  DFS(1, 0, 0, 0);
  cout << ans.size() << '\n';
  for (auto it : ans) cout << it << '\n';
  cout << '\n';
  return 0;
}
