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).
'''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
'''

from sys import stdin, setrecursionlimit
from collections import defaultdict
setrecursionlimit(15000)


def counter(num):
	if num == 0:
		return 1
	else:
		return 0


def flip_me(original, count, index):
	if count % 2 == 0:
		return original[index]
	else:
		return counter(original[index])


def dfs(graph, visited, ans, original, goal, change, node):
	visited[node] = True

	value = flip_me(original, change[node], node - 1)
	add = 0
	if goal[node - 1] == value:
		pass
	else:
		add = 1
		ans.append(node)
	
	for i in  graph[node]:
		if visited[i] == False:
			for j in graph[i]:
				if visited[j] == False:
					change[j] += change[node] + add

			dfs(graph, visited, ans, original, goal, change, i)


def calculate(graph, original, goal):
	visited = dict()
	change = dict()
	for i in graph:
		visited[i] = False
		change[i] = 0
	ans = []
	dfs(graph, visited, ans, original, goal, change, 1)
	return ans

# main starts 
n = int(stdin.readline().strip())
graph = defaultdict(list)
for _ in range(n - 1):
	u, v = list(map(int, stdin.readline().split()))
	graph[u].append(v)
	graph[v].append(u)

original = list(map(int, stdin.readline().split()))
goal = list(map(int, stdin.readline().split()))
count = [0]
ans = calculate(graph, original, goal)
print(len(ans))
for i in ans:
	print(i)