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).
def dfs(node,parent):
    global a,init,goal,l,t
    if init[node-1]!=goal[node-1]:
        update(node,parent,0)
        l=l+1
        t.append(node)
    for i in range(len(a[node])):
        if a[node][i]!=parent:
            dfs(a[node][i],node)
def update(node,parent,p):
    global a,init,goal
    if p%2==0:
        init[node-1]=(init[node-1]^1)
    for i in range(len(a[node])):
        if a[node][i]!=parent:
            update(a[node][i],node,p+1)
    
n = int(input())
import sys
sys.setrecursionlimit(10**6)
a = [[] for _ in range(n+1)]
visited = [False for _ in range(n+1)]
for _ in range(n-1):
    x,y = list(map(int,input().split()))
    a[x].append(y)
    a[y].append(x)
l = 0
init = list(map(int,input().split()))
goal = list(map(int,input().split()))
t = []
dfs(1,0)
print(l)
for i in t:
    print(i)
