from math import inf


def main():
    N = int(input())
    A = sorted(map(int, input().split()))
    B = sorted(map(int, input().split()))

    ans = []
    left_diff = 0
    right_diff = sum(abs(a_elm-b_elm) for a_elm, b_elm in zip(A[1:], B))
    ans.append(right_diff)
    for idx, v in enumerate(A[1:], 1):
        left_diff += abs(A[idx-1]-B[idx-1])
        right_diff -= abs(v-B[idx-1])
        ans.append(left_diff+right_diff)

    ans_length = set()
    min_v = inf
    for a_elm, ans_elm in zip(A, ans):
        if min_v < ans_elm:
            continue
        if min_v == ans_elm:
            ans_length.add(a_elm)
            continue

        min_v = ans_elm
        ans_length.clear()
        ans_length.add(a_elm)
    print(len(ans_length))
    print(*sorted(ans_length))


if __name__ == "__main__":
    main()