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.BufferedWriter;
import java.util.InputMismatchException;
import java.util.ArrayList;
import java.util.List;
import java.util.NoSuchElementException;
import java.math.BigInteger;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.Collections;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.util.Comparator;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 * @author Nguyen Trung Hieu - vuondenthanhcong11@gmail.com
 */
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(1, in, out);
        out.close();
    }
}

class TaskA {
    ArrayList<Integer> answer = new ArrayList<Integer>();
    public void solve(int testNumber, InputReader in, OutputWriter out) {
        int count = in.readInt();
        int[] from = new int[count - 1];
        int[] to = new int[count - 1];
        IOUtils.readIntArrays(in, from, to);
        MiscUtils.decreaseByOne(from, to);

        int[][] graph = GraphUtils.buildSimpleGraph(count, from, to);

        int[] begin = IOUtils.readIntArray(in, count);
        int[] goal = IOUtils.readIntArray(in, count);

        if (begin[0] != goal[0])
            answer.add(1);
        dfs(0, -1, 0, begin[0] != goal[0], begin, goal, graph);
        for (int x : graph[0]) {
            if (begin[x] != goal[x])
                answer.add(x + 1);
            dfs(x, 0, 0, begin[x] != goal[x], begin, goal, graph);
        }

        out.printLine(answer.size());
        for (int x : answer)
            out.printLine(x);
    }

    private void dfs(int cur, int from, int deep, boolean needFlip, int[] begin, int[] goal, int[][] graph) {
        if (needFlip && deep % 2 == 0)
            begin[cur] ^= 1;
        if (begin[cur] != goal[cur] && deep % 2 == 0) {
            needFlip = !needFlip;
            answer.add(cur + 1);
        }
        for (int x : graph[cur]) {
            if (x == from)
                continue;
            dfs(x, cur, deep + 1, needFlip, begin, goal, graph);
        }
    }
}

class InputReader {
    private InputStream stream;
    private byte[] buf = new byte[1024];
    private int curChar;
    private int numChars;
    private SpaceCharFilter filter;

    public InputReader(InputStream stream) {
        this.stream = stream;
    }

    public int read() {
        if (numChars == -1)
            throw new InputMismatchException();
        if (curChar >= numChars) {
            curChar = 0;
            try {
                numChars = stream.read(buf);
            } catch (IOException e) {
                throw new InputMismatchException();
            }
            if (numChars <= 0)
                return -1;
        }
        return buf[curChar++];
    }

    public int readInt() {
        int c = read();
        while (isSpaceChar(c))
            c = read();
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res *= 10;
            res += c - '0';
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public boolean isSpaceChar(int c) {
        if (filter != null)
            return filter.isSpaceChar(c);
        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }

    public interface SpaceCharFilter {
        public boolean isSpaceChar(int ch);
    }

}

class OutputWriter {
    private final PrintWriter writer;

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

    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();
    }

}

class IOUtils {

    public static int[] readIntArray(InputReader in, int size) {
        int[] array = new int[size];
        for (int i = 0; i < size; i++)
            array[i] = in.readInt();
        return array;
    }

    public static void readIntArrays(InputReader in, int[]... arrays) {
        for (int i = 0; i < arrays[0].length; i++) {
            for (int j = 0; j < arrays.length; j++)
                arrays[j][i] = in.readInt();
        }
    }

}

class MiscUtils {

    public static void decreaseByOne(int[]...arrays) {
        for (int[] array : arrays) {
            for (int i = 0; i < array.length; i++)
                array[i]--;
        }
    }

}

class GraphUtils {
    public static int[][] buildGraph(int vertexCount, int[] from, int[] to) {
        int edgeCount = from.length;
        int[] degree = new int[vertexCount];
        for (int i = 0; i < edgeCount; i++) {
            degree[from[i]]++;
            degree[to[i]]++;
        }
        int[][] graph = new int[vertexCount][];
        for (int i = 0; i < vertexCount; i++)
            graph[i] = new int[degree[i]];
        for (int i = 0; i < edgeCount; i++) {
            graph[from[i]][--degree[from[i]]] = i;
            graph[to[i]][--degree[to[i]]] = i;
        }
        return graph;
    }

    public static int otherVertex(int vertex, int from, int to) {
        return from + to - vertex;
    }

    public static int[][] buildSimpleGraph(int vertexCount, int[] from, int[] to) {
        int[][] graph = buildGraph(vertexCount, from, to);
        simplifyGraph(from, to, graph);
        return graph;
    }

    private static void simplifyGraph(int[] from, int[] to, int[][] graph) {
        for (int i = 0; i < graph.length; i++) {
            for (int j = 0; j < graph[i].length; j++) {
                graph[i][j] = otherVertex(i, from[graph[i][j]], to[graph[i][j]]);
            }
        }
    }

}