N=int(input())
list1=list(map(str,input().split()))
list2=list(map(str,input().split()))

if N==1:
    print(1)
    print(list1[0])
    print(list2[0])
else:
    for i in range(N):
        if list1[i]!=list2[i]:
            print(i+1)
            print(list1[i])
            print(list2[i])