#include <bits/stdc++.h>
using namespace std;
const long long N = 1e5 + 5;
long long n, ans = 0;
long long a[N], b[N];
vector<long long> g[N];
vector<long long> v;
long long visited[N];
void dfs(long long k, long long lvl, long long odd, long long even) {
  visited[k] = 1;
  if (lvl % 2) {
    if (odd % 2) {
      a[k] = a[k] ^ 1;
    }
    if (a[k] != b[k]) {
      odd++;
      ans++;
      v.push_back(k);
    }
  } else {
    if (even % 2) {
      a[k] = a[k] ^ 1;
    }
    if (a[k] != b[k]) {
      even++;
      ans++;
      v.push_back(k);
    }
  }
  for (auto it : g[k]) {
    if (visited[it] == 0) {
      dfs(it, lvl + 1, odd, even);
    }
  }
}
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  cin >> n;
  for (long long i = 1; i <= n - 1; i++) {
    long long u, v;
    cin >> u >> v;
    g[u].push_back(v);
    g[v].push_back(u);
  }
  for (long long i = 1; i <= n; i++) cin >> a[i];
  for (long long i = 1; i <= n; i++) cin >> b[i];
  dfs(1, 1, 0, 0);
  cout << ans << "\n";
  for (auto it : v) cout << it << "\n";
  return 0;
}
