n=int(input())
a=list(map(int,input().split()))
b=list(map(int,input().split()))
a.sort()
b.sort()
ans=0
sets=set([a[0]])
tmp=0
for i in range(n-1):
    tmp+=abs(a[i+1]-b[i])
ans=tmp
for i in range(n-1):
    tmp-=abs(a[i+1]-b[i])
    tmp+=abs(a[i]-b[i])
    if ans>tmp:
        ans=tmp
        sets=set([a[i+1]])
    elif ans==tmp:
        sets.add(a[i+1])
print(len(sets))
print(*sorted(sets))