#include<bits/stdc++.h>
#define N 1000005
using namespace std;
int a[N],b[N],n,ct[N],pos[N],ret[N],tt;
#define pii pair<int,int>
#define fi first
#define se second
set<pii>s;
int main(){
	scanf("%d",&n);
	int mx=0;
	for(int i=1;i<=n;++i)scanf("%d",&a[i]),mx=max(mx,a[i]),++ct[a[i]];
	for(int i=1;i<=n;++i)scanf("%d",&b[i]),pos[b[i]]=i,--ct[b[i]];
	for(int i=1;i<=n;++i)if(ct[i]!=0)puts("-1"),exit(0);
	if(mx<=2){
		int f=1;
		for(int i=1;i<=n;++i)f&=(a[i]==b[n-i+1]);
		if(f){
			puts("1");
			for(int i=1;i<n;++i)printf("1 ");printf("1\n");
			for(int i=1;i<n;++i)printf("1 ");printf("1\n");
		}else{
			puts("2");
			for(int i=1;i<n;++i)printf("%d ",a[i]);printf("%d\n",a[n]);
			for(int i=1;i<n;++i)printf("%d ",b[i]);printf("%d\n",b[n]);
		}return 0;
	}
	for(int i=1;i<=n;++i){
		if(!s.size()||(*(--s.end())).fi<pos[a[i]]){
			int q=pos[a[i]];
			++tt,ret[i]=tt;
			s.insert(make_pair(q,tt));
		}else{
			set<pii>::iterator it=s.lower_bound(make_pair(pos[a[i]],0));
			ret[i]=(*it).se;s.erase(it),s.insert(make_pair(pos[a[i]],ret[i]));
		}
	}
	printf("%d\n",tt);
	for(int i=1;i<=n;++i)printf("%d ",ret[i]),pos[a[i]]=i;
	printf("\n");
	for(int i=1;i<=n;++i)printf("%d ",ret[pos[b[i]]]);printf("\n");
	return 0;
}