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 raw_ints():
    ln = input()
    ret = [ x for x in map(int, ln.strip().split()) ]
    return ret

def raw_int():
    ln = input()
    return int(ln)
    # return [ xmap(int, ln.strip().split())[0]

def flip(n, node, edges, goal, init):

    ret = []
    queue = [ (node, True) ]
    seen  = {node}


    while len(queue) != 0:

        current, should_flip = queue.pop()

        if should_flip and init[node - 1] != goal[node - 1] :
            #print("Flipping: ", node)
            ret.append(node)
            init[node - 1] = not init[node - 1]
        else:
            pass
            # print("Already correct")

        for a, b in edges:

            if b not in seen and a == node:
                queue.append( ( b, not should_flip ))
                seen.add(b)
            if a not in seen and b == node:
                queue.append( ( a, not should_flip ))
                seen.add(a)

    return ret

if __name__ == '__main__':

    n = raw_int()

    edges = []
    for i in range(n - 1):
        a, b = raw_ints()
        edges.append([a, b])

    init = raw_ints()
    goal = raw_ints()

    solution = []

    queue = [1]
    seen = set()

    while len(queue) > 0:

        node = queue.pop()
        seen.add(node)
        # print("at node:", node, init[node-1], goal[node-1])
        if goal[node-1] != init[node-1]:
            # print("flipping")
            solution = solution + flip(n, node, edges, goal, init)
        else:
            pass
            # print("not flipping")

        for a, b in edges:
            if b not in seen and a == node:
                queue.append(b)
            if a not in seen and b == node:
                queue.append(a)
        # print("done flipping")
    # print(solution)
    print(len(solution))
    for v in solution:
        print(v)
    # print(edges)
