#include <bits/stdc++.h>
using namespace std;
const int mx = 2e5 + 3;
vector<int> v[mx];
int col[mx];
bool vis[mx];
int total = 0;
int x[mx], y[mx];
void init() {
  for (int i = 0; i < mx; i++) vis[i] = 0;
}
vector<int> vec;
void dfs(int no, int pn, int p, int q) {
  x[no] ^= p;
  if (x[no] != y[no]) {
    p ^= 1;
    vec.push_back(no + 1);
  }
  for (auto i : v[no]) {
    if (i != pn) {
      dfs(i, no, q, p);
    }
  }
}
void solve() {
  init();
  int n;
  cin >> n;
  int a, b;
  for (int i = 1; i < n; i++) {
    cin >> a >> b;
    a--;
    b--;
    v[a].push_back(b);
    v[b].push_back(a);
  }
  for (int i = 0; i < n; i++) cin >> x[i];
  for (int i = 0; i < n; i++) cin >> y[i];
  dfs(0, -1, 0, 0);
  cout << vec.size() << endl;
  for (int i = 0; i < vec.size(); i++) cout << vec[i] << " ";
}
int32_t main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int t = 1;
loop:
  while (t--) {
    solve();
  }
}
