Problem: Iahub is very proud of his recent discovery, propagating trees. Right now, he invented a new tree, called xor-tree. After this new revolutionary discovery, he invented a game for kids which uses xor-trees.

The game is played on a tree having n nodes, numbered from 1 to n. Each node i has an initial value initi, which is either 0 or 1. The root of the tree is node 1.

One can perform several (possibly, zero) operations on the tree during the game. The only available type of operation is to pick a node x. Right after someone has picked node x, the value of node x flips, the values of sons of x remain the same, the values of sons of sons of x flips, the values of sons of sons of sons of x remain the same and so on.

The goal of the game is to get each node i to have value goali, which can also be only 0 or 1. You need to reach the goal of the game by using minimum number of operations.

Input

The first line contains an integer n (1 ≤ n ≤ 105). Each of the next n - 1 lines contains two integers ui and vi (1 ≤ ui, vi ≤ n; ui ≠ vi) meaning there is an edge between nodes ui and vi. 

The next line contains n integer numbers, the i-th of them corresponds to initi (initi is either 0 or 1). The following line also contains n integer numbers, the i-th number corresponds to goali (goali is either 0 or 1).

Output

In the first line output an integer number cnt, representing the minimal number of operations you perform. Each of the next cnt lines should contain an integer xi, representing that you pick a node xi.

Examples

Input

10
2 1
3 1
4 2
5 1
6 2
7 5
8 6
9 8
10 5
1 0 1 1 0 1 0 1 0 1
1 0 1 0 0 1 1 1 0 1


Output

2
4
7

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;


public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        TaskA solver = new TaskA();
        solver.solve(in, out);
        out.close();
    }
}

class Graph {

    private List<Integer> neighbours[];

    @SuppressWarnings("unchecked")
    public Graph(int n) {
        neighbours = new List[n];
        for (int i = 0; i < n; i++) {
            neighbours[i] = new ArrayList<>();
        }
    }

    public void addEdge(int from, int to) {
        --from;
        --to;
        neighbours[from].add(to);
        neighbours[to].add(from);
    }

    public List<Integer> neighbours(int v) {
        return neighbours[v];
    }
}



class TaskA {


    private int actualValues[];
    private int expectedValues[];
    private Graph G;
    private boolean visited[];
    private int number = 0;

    private List<Integer> checkpoints = new ArrayList<>();

    public void dfs(int v, int even, int odd, int number) {
        if(visited[v]) return;
        if(number % 2 == 0) {
            even = even + neededChange(v, even);
        } else {
            odd = odd + neededChange(v, odd);
        }
        visited[v] = true;
        for (int neighbour : G.neighbours(v)) {
                dfs(neighbour, even, odd, number + 1);
        }
    }

    private int neededChange(int v, int numberOfTimes) {
        int val = actualValues[v];
        if(numberOfTimes % 2 == 1) {
            if(actualValues[v] == 1) {
                val = 0;
            } else {
                val = 1;
            }
        }

        if(val == expectedValues[v]) {
            return 0;
        }

        number++;
        checkpoints.add(v+1);
        return 1;
    }


    public void solve(InputReader in, OutputWriter out) {
        int n = in.nextInt();
        G = new Graph(n);
        int from, to;
        visited = new boolean[n];
        actualValues = new int[n];
        expectedValues = new int[n];
        for (int i = 0; i < n - 1; i++) {
            from = in.nextInt();
            to = in.nextInt();
            G.addEdge(from, to);
        }
        for (int i = 0; i < n; i++) {
            actualValues[i] = in.nextInt();
            visited[i] = false;
        }
        for (int i = 0; i < n; i++) {
            expectedValues[i] = in.nextInt();
        }

        dfs(0,0,0,0);

        out.printLine(number);
        for (int checkpoint : checkpoints) {
            out.printLine(checkpoint);
        }


    }
}

class InputReader {
    public BufferedReader reader;
    public StringTokenizer tokenizer;

    public InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream), 32768);
        tokenizer = null;
    }

    public String next() {
        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }
    public long nextLong() {
        return Long.parseLong(next());
    }

}

class OutputWriter {
    private final PrintWriter writer;

    public OutputWriter(OutputStream outputStream) {
        writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void print(Object... objects) {
        for (int i = 0; i < objects.length; i++) {
            if (i != 0) {
                writer.print(' ');
            }
            writer.print(objects[i]);
        }
    }

    public void printLine(Object... objects) {
        print(objects);
        writer.println();
    }

    public void close() {
        writer.close();
    }

}