from itertools import accumulate def cumsum(seq, reverse=False) -> list: if reverse: res = cumsum(reversed(seq)) res.reverse() return res return list(accumulate(seq)) INF = 1 << 60 N = int(input()) A = list(map(int, input().split())) B = list(map(int, input().split())) A.sort() B.sort() lefts = [] for a, b in zip(A, B): lefts.append(abs(a - b)) rights = [] for a, b in zip(A[1:], B): rights.append(abs(a - b)) lacc = cumsum(lefts) racc = [0] + cumsum(rights, reverse=True) min_d = INF # 不満度 s = set() for i in range(N): # i 番目のハチマキを残したときの不満度 x = lacc[i-1] if i > 0 else 0 y = racc[i+1] if i+1 < N else 0 d = x + y if min_d > d: min_d = d s.clear() if min_d == d: s.add(A[i]) print(len(s)) print(*s)