n=int(input())
a=sorted(list(map(int,input().split())))
b=sorted(list(map(int,input().split())))
x=[0]
y=[0]
for i in range(n-1):
	x.append(x[-1]+abs(a[i]-b[i]))
	y.append(y[-1]+abs(a[i+1]-b[i]))
z=[]
for i in range(n):
	z.append((x[i]+y[-1]-y[i],i))
z.sort()
ans=set()
i=0
while i<n and z[i][0]==z[0][0]:
	ans.add(a[z[i][1]])
	i+=1 
print(len(ans))
print(*ans)