#include <bits/stdc++.h>
using namespace std;
char alpha[26] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
                  'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r',
                  's', 't', 'u', 'v', 'w', 'x', 'y', 'z'};
vector<int> adj[100001];
vector<int> cmp(100001);
vector<int> ideal(100001);
void addEdge(int u, int v) {
  adj[u].push_back(v);
  adj[v].push_back(u);
}
int ans = 0;
vector<int> vec;
void dfs(int src, int par, int depth, int od, int ev) {
  depth += 1;
  if (depth % 2) {
    if (od % 2) {
      if (cmp[src] == ideal[src]) {
        ans++;
        vec.push_back(src);
        od++;
      }
    } else {
      if (cmp[src] != ideal[src]) {
        ans++;
        vec.push_back(src);
        od++;
      }
    }
  }
  if (depth % 2 == 0) {
    if (ev % 2) {
      if (cmp[src] == ideal[src]) {
        ans++;
        vec.push_back(src);
        ev++;
      }
    } else {
      if (cmp[src] != ideal[src]) {
        ans++;
        vec.push_back(src);
        ev++;
      }
    }
  }
  for (auto child : adj[src]) {
    if (child != par) {
      dfs(child, src, depth, od, ev);
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n;
  cin >> n;
  int u, v;
  for (int i = 1; i < n; i++) {
    cin >> u >> v;
    addEdge(u, v);
  }
  for (int i = 1; i <= n; i++) {
    cin >> cmp[i];
  }
  for (int i = 1; i <= n; i++) {
    cin >> ideal[i];
  }
  dfs(1, 0, 0, 0, 0);
  cout << ans << '\n';
  for (int i : vec) {
    cout << i << '\n';
  }
}
