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.util.*;
import java.math.*;
import java.io.*; 
 public class B{
static int[] dx={-1,1,0,0};
static int[] dy={0,0,1,-1};
    static FastReader scan=new FastReader();
   public static PrintWriter out = new PrintWriter (new BufferedOutputStream(System.out));
  static ArrayList<Pair>es;
  static LinkedList<Integer>edges[];
   static boolean prime[];
   static void sieve(int n) 
    { 
        
        prime = new boolean[n+1]; 
        for(int i=0;i<n;i++) 
            prime[i] = true; 
          
        for(int p = 2; p*p <=n; p++) 
        { 
           
            if(prime[p] == true) 
            { 
                
                for(int i = p*p; i <= n; i += p) 
                    prime[i] = false; 
            } 
        } 
          
        
    }      
     public static int lowerBound(long[] array, int length, long value) {
        int low = 0;
        int high = length;
        while (low < high) {
            final int mid = (low + high) / 2;
            //checks if the value is less than middle element of the array
            if (value <= array[mid]) {
                high = mid;
            } else {
                low = mid + 1;
            }
        }
        return low;
    }
    public static int upperBound(long[] array, int length, long value) {
        int low = 0;
        int high = length;
        while (low < high) {
            final int mid = low+(high-low) / 2;
            if ( array[mid]>value) {
                high = mid ;
            } else {
                low = mid+1;
            }
        }
        return low;
    }
static long mod(long x,long y)
    {
        if(x<0)
            x=x+(-x/y+1)*y;
        return x%y;
    }    
    static boolean isPowerOfTwo(int n)
{
    if(n==0)
    return false;
 
return (int)(Math.ceil((Math.log(n) / Math.log(2)))) == 
       (int)(Math.floor(((Math.log(n) / Math.log(2)))));
}

  
   
static boolean isprime(long x)
           {
            for(long i=2;i*i<=x;i++)
                if(x%i==0)
                    return false;
                return true;
           }


static int dist(int x1,int y1,int x2,int y2){
return Math.abs(x1-x2)+Math.abs(y1-y2);
}


    static long cuberoot(long x)
    {
        long lo = 0, hi = 1000005;
        while(lo<hi)
        {
            long m = (lo+hi+1)/2;
            if(m*m*m>x)
                hi = m-1;
            else
                lo = m;
        }
        return lo;
    }
     public static int log2(int N) 
    { 
  
        // calculate log2 N indirectly 
        // using log() method 
        int result = (int)(Math.log(N) / Math.log(2)); 
  
        return result; 
    } 
  
    
   
       static int gcd(int a, int b) {
    if(a!=0&&b!=0)
        while((a%=b)!=0&&(b%=a)!=0);
    return a^b;
}
    static int LCM(int a,int b){
    return (Math.abs(a*b))/gcd(a,b);
   }
   public static class comp1 implements Comparator<Integer>{  
public int compare(Integer o1,Integer o2){
return Math.abs(o1)-Math.abs(o2);
}
  }
  static int n,k;
  static int arr[];
  static boolean ok(int x)
{
    int cnt=0;
    for(int i=0;i<n;i++)
    {
        if(arr[i]<=x)
            cnt++;
        
    }
    if(cnt==k)
        return true;
    else return false;
}
static boolean isSubSequence(String str1,  
                    String str2, int m, int n) 
    { 
        int j = 0; 
          
        // Traverse str2 and str1, and compare  
        // current character of str2 with first 
        // unmatched char of str1, if matched  
        // then move ahead in str1 
        for (int i = 0; i < n && j < m; i++) 
            if (str1.charAt(j) == str2.charAt(i)) 
                j++; 
  
        // If all characters of str1 were found 
        // in str2 
        return (j == m);  
    } 
    static int goal[],init[];
    static ArrayList<Integer>sol;
    static boolean vis[];
static int count=0;
    static void dfs1(int x,int cur,int even,int odd,int level)
    {
        vis[x]=true;
        if(cur!=goal[x])
        {   
            if(level%2==0)
              even++;
            else  
odd++;

                sol.add(x);
        }
        for(int i:edges[x])
        {
            if(!vis[i]){
                if(level%2==0)
                dfs1(i,(odd+init[i])%2,even,odd,level+1);
            else 
                dfs1(i,(even+init[i])%2,even,odd,level+1);

            }
        }

    }
    
public static void main(String[] args)  throws Exception 
{
//java.util.Scanner scan=new java.util.Scanner(new File("mootube.in"));
 //PrintWriter out = new PrintWriter (new FileWriter("mootube.out"));
 //scan=new FastReader("input.txt");
 //out = new PrintWriter ("output.txt");
 //System.out.println(~-1);
//System.out.println(2<<5);
    //System.out.println(0^1023);
//System.out.println(gcd(672,840));

  int tt=1;
//tt=scan.nextInt();
 outer:while(tt-->0)
 {
  int n=scan.nextInt();
  edges=new LinkedList[n+1];
  sol=new ArrayList<Integer>();
  for(int i=0;i<=n;i++)
    edges[i]=new LinkedList();
vis=new boolean[n];
 init=new int[n];
goal=new int[n];
  for(int i=0;i<n-1;i++)
  {
    int a=scan.nextInt()-1,b=scan.nextInt()-1;
    edges[a].add(b);
    edges[b].add(a);
  }
  for(int i=0;i<n;i++)
    init[i]=scan.nextInt();
for(int i=0;i<n;i++)
    goal[i]=scan.nextInt();
dfs1(0,init[0],0,0,0);

out.println(sol.size());
for(int k:sol)
out.println(k+1);
}

out.close();
    
}
static long binexp(long a,long n,long mod)
{
    if(n==0)
        return 1;
    long res=binexp(a,n/2,mod)%mod;
    res=res*res;
    if(n%2==1)
        return (res*a)%mod;
    else 
        return res%mod;
}
static class special implements Comparable<special>{
    int x;
    char id;
    special(int x,char id)
    {
        this.id=id;
       this.x=x;
    }
    public int compareTo(special o)
    {
        
        return x-o.x;
    }
   
}
 public static  long pow(long b, long e) {
            long r = 1;
            while (e > 0) {
                if (e % 2 == 1) r = r * b ;
                b = b * b;
                e >>= 1;
            }
            return r;
        }

private static void sort(int[] arr) {
        List<Integer> list = new ArrayList<>();
        for (int object : arr) list.add(object);
        Collections.sort(list);
        for (int i = 0; i < list.size(); ++i) arr[i] = list.get(i);
    }
 public static class FastReader {
        BufferedReader br;
        StringTokenizer root;
        
 
        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }
        FastReader(String filename)throws Exception
        {

            br=new BufferedReader(new FileReader(filename));
        }
 
        String next() {
            while (root == null || !root.hasMoreTokens()) {
                try {
                    root = new StringTokenizer(br.readLine());
                } catch (Exception addd) {
                    addd.printStackTrace();
                }
            }
            return root.nextToken();
        }
 
        int nextInt() {
            return Integer.parseInt(next());
        }
 
        double nextDouble() {
            return Double.parseDouble(next());
        }
 
        long nextLong() {
            return Long.parseLong(next());
        }
 
        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (Exception addd) {
                addd.printStackTrace();
            }
            return str;
        }
         public int[] nextIntArray(int arraySize) {
            int array[] = new int[arraySize];
 
            for (int i = 0; i < arraySize; i++) {
                array[i] = nextInt();
            }
 
            return array;
        }
}
public static class Pair implements Comparable<Pair>{
         int x;
         int y;
        
        int id;
        public Pair(){}
        public Pair(int x1, int y1,int id) {
            x=x1;
            y=y1;
            this.id=id;
        }
        public Pair(int x1, int y1) {
            x=x1;
            y=y1;
        
        }
        @Override
        public int hashCode() {
            return (int)(x + 31 * y);
        }
        public String toString() {
            return x + " " + y;
        }
        @Override
        public boolean equals(Object o){
            if (o == this) return true;
            if (o.getClass() != getClass()) return false;
            Pair t = (Pair)o;
            return t.x == x && t.y == y;
        }
        public  int compareTo(Pair o)
        {
            if(x==o.x)
                return y-o.y;
        return x-o.x;
        }
}

}