import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################

n = ni()

a = na()
b = na()
a.sort()
b.sort()

s = 0
for i in range(n-1):
    s += abs(a[i+1] - b[i])

f = [s]
for i in range(n-1):
    s += abs(a[i] - b[i]) - abs(a[i+1] - b[i])
    f.append(s)

m = min(f)

ans = sorted(set([a[i] for i in range(n) if f[i] == m]))
print(len(ans))
print(*ans)