#include <bits/stdc++.h>
using namespace std;
void fast() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
}
vector<vector<long long> > adj;
vector<bool> vis;
long long parents[100001], grandparents[100001], flips[100001];
void dfs(long long node) {
  vis[node] = true;
  for (auto i : adj[node]) {
    if (!vis[i]) {
      parents[i] = node;
      dfs(i);
    }
  }
}
int main() {
  fast();
  long long t, n, i, j, k, x, y, c, m;
  cin >> n;
  adj.resize(n);
  vis.resize(n);
  fill(vis.begin(), vis.end(), false);
  vector<long long> init(n);
  vector<long long> targ(n);
  for (long long i = 0; i < n - 1; i += 1) {
    cin >> x >> y;
    x--;
    y--;
    adj[x].push_back(y);
    adj[y].push_back(x);
  }
  for (long long i = 0; i < n; i += 1) cin >> init[i];
  ;
  for (long long i = 0; i < n; i += 1) cin >> targ[i];
  ;
  memset(grandparents, (-1), sizeof(grandparents));
  dfs(0);
  for (long long i = 0; i < n; i += 1) {
    if (i == 0) {
      continue;
    }
    if (parents[i] == 0) {
      continue;
    }
    grandparents[i] = parents[parents[i]];
  }
  queue<long long> nodes;
  vector<long long> res;
  nodes.push(0);
  fill(vis.begin(), vis.end(), false);
  while (!nodes.empty()) {
    i = nodes.front();
    vis[i] = true;
    nodes.pop();
    if (grandparents[i] == -1) {
      if (init[i] != targ[i]) {
        res.push_back(i + 1);
        flips[i] = 1;
      }
    } else {
      if (flips[grandparents[i]] & 1) {
        init[i] = 1 - init[i];
      }
      if (init[i] == targ[i]) {
        flips[i] = flips[grandparents[i]];
      } else {
        res.push_back(i + 1);
        flips[i] = flips[grandparents[i]] + 1;
      }
    }
    for (auto num : adj[i]) {
      if (!vis[num]) {
        nodes.push(num);
      }
    }
  }
  cout << res.size() << '\n';
  for (long long i = 0; i < res.size(); i += 1) {
    cout << res[i] << '\n';
  }
}
