n=int(input())
A=list(map(int,input().split()))
B=list(map(int,input().split()))
A.sort()
B.sort()
kazu=sum([abs(A[i+1]-B[i]) for i in range(n-1)])
C=[(kazu,0)]
for i in range(n-1):
	kazu+=abs(A[i]-B[i])-abs(A[i+1]-B[i])
	C.append((kazu,i+1))
mx=min([x[0] for x in C])
ans=set()
for i in range(n):
	if C[i][0]==mx:
		ans.add(A[C[i][1]])
print(len(ans))
print(*sorted(list(ans)))