#include<bits/stdc++.h>
#include<vector>

using namespace std;

int res;
vector<int> roots, init, goal;
vector<vector<int>> suka(100000);

void DFS(int branch, vector<int> change, int level){
    if (abs(init[branch-1] - change[level]) == goal[branch-1]){
        for(int v:suka[branch]){
            DFS(v, change, 1-level);
        }
    }
    else{
        res++;
        roots.push_back(branch);
        change[level] = 1 - change[level];
        for(int v:suka[branch]){
            DFS(v, change, 1-level);
        }
    }
}
int main(){
    int n, child, dad, num;
    cin>>n;
    cin>>child>>dad;
    if (child != 1){
        suka[dad].push_back(child);
        for (int i = 3; i < n+1; i++){
            cin>>child>>dad;
            suka[dad].push_back(child);
    }}
    else{
        suka[child].push_back(dad);
        for (int i = 3; i < n+1; i++){
            cin>>child>>dad;
            suka[child].push_back(dad);
    }
    }
    for (int i = 0; i < n; i++){
        cin >> num;
        init.push_back(num);
    }
    for (int i = 0; i < n; i++){
        cin >> num;
        goal.push_back(num);
    }
    vector<int> c (2, 0);
    DFS(1, c, 0);
    cout<<res;
    for (int i = 0; i < res; i++){
        cout<<endl<<roots[i];
    }
    return 0;
}