#include <bits/stdc++.h>
using namespace std;
const int inf = int(1e9);
const double eps = 1e-9;
const double pi = 4 * atan(double(1));
const int N = int(1e5) + 100;
bool used[N];
int init[N], goal[N];
vector<int> g[N];
vector<int> ans;
void dfs(int v, int col, int iadd[2]) {
  used[v] = true;
  int add[2];
  add[0] = iadd[0];
  add[1] = iadd[1];
  if (init[v] ^ add[col] != goal[v]) {
    ans.push_back(v);
    add[col] ^= 1;
  }
  for (int i = 0; i < int((g[v]).size()); ++i) {
    if (!used[g[v][i]]) {
      dfs(g[v][i], col ^ 1, add);
    }
  }
}
int main() {
  int n;
  scanf("%d", &n);
  for (int i = 0; i < n - 1; ++i) {
    int a, b;
    scanf("%d %d", &a, &b);
    --a;
    --b;
    g[a].push_back(b);
    g[b].push_back(a);
  }
  for (int i = 0; i < n; ++i) {
    scanf("%d", &init[i]);
  }
  for (int i = 0; i < n; ++i) {
    scanf("%d", &goal[i]);
  }
  int add[2];
  add[0] = add[1] = 0;
  dfs(0, 0, add);
  printf("%d\n", int((ans).size()));
  for (int i = 0; i < int((ans).size()); ++i) {
    printf("%d\n", ans[i] + 1);
  }
  return 0;
}
