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 *init*<sub class="lower-index">*i*</sub>, 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 *goal*<sub class="lower-index">*i*</sub>, which can also be only 0 or 1. You need to reach the goal of the game by using minimum number of operations.
The first line contains an integer *n* (1 ≤ *n* ≤ 10<sup class="upper-index">5</sup>). Each of the next *n* - 1 lines contains two integers *u*<sub class="lower-index">*i*</sub> and *v*<sub class="lower-index">*i*</sub> (1 ≤ *u*<sub class="lower-index">*i*</sub>, *v*<sub class="lower-index">*i*</sub> ≤ *n*; *u*<sub class="lower-index">*i*</sub> ≠ *v*<sub class="lower-index">*i*</sub>) meaning there is an edge between nodes *u*<sub class="lower-index">*i*</sub> and *v*<sub class="lower-index">*i*</sub>. 

The next line contains *n* integer numbers, the *i*-th of them corresponds to *init*<sub class="lower-index">*i*</sub> (*init*<sub class="lower-index">*i*</sub> is either 0 or 1). The following line also contains *n* integer numbers, the *i*-th number corresponds to *goal*<sub class="lower-index">*i*</sub> (*goal*<sub class="lower-index">*i*</sub> is either 0 or 1).
import math
import sys
from collections import defaultdict
import heapq
#input = sys.stdin.readline
USE_FILE = False 

def search(k, v):
    p = 0
    a, n = len(v), len(v)
    while a >= 1:
        while p + a < n and k > v[p+a]:
            p += a
        a //= 2
    if k > v[p+a]:
        p += 1
    return p+1

def sum_digits(nr):
    return sum([int(i) for i in str(nr)])

def clean_heap(heap, count):
    while heap and count[heap[0]] <= 0:
        heapq.heappop(heap)

def dfs(start, level = 0):
    if level % 2 == 0:
        actual_values[start] ^= 1
    for e in tree[start]: 
        dfs(e, level + 1)




def main():
    global actual_values
    global goal_values
    global tree
    tree = defaultdict(list)
    n = int(input())
    for i in range(n-1):
        x, y = tuple(map(int, input().split()))
        tree[x].append(y)
    actual_values = [int(i) for i in input().split()]
    goal_values = [int(i) for i in input().split()]
    moves = 0
    picked = []
    for i in range(len(actual_values)):
        if actual_values[i] != goal_values[i]:
            moves += 1
            picked.append(i+1)
            dfs(i)
    print(moves)
    for p in picked:
        print(p)


if __name__=="__main__":
    if USE_FILE:
        sys.stdin = open('/home/stefan/input.txt', 'r')
    main()
