#include<iostream>
#include<algorithm>
#include<stdio.h>
#include<math.h>
#include<set>
#include<vector>
#include<string.h>
#include<string>
using namespace std;

int arrstart[14326];
int arrend[14326];

int a[14326];

bool assert(bool t)
{
    if (!t)
        throw 42;
    return true;
}

int cntOst(int a, int b)
{
    int res = a%b;
    if (res < 0)
        res += b;
    return res;
}

int main()
{
#ifdef _DEBUG
    freopen("in.txt","r",stdin);
#endif

    int m;
    cin >> m;

    int zeroCnt = 0;
    int ost = -1;
    int sum1=0,sum2=0;

    for (int i=0; i<m; i++)
    {
        cin >> arrstart[i];
        sum1 += arrstart[i];
        if (arrstart[i] == 0)
            zeroCnt++;
    }

    if (zeroCnt > 1)
    {
        cout << "-1";
        return 0;
    }

    for (int j=0; j<m; j++)
    {
        cin >> arrend[j];
        sum2 += arrend[j];
    }

    if (sum1 != sum2)
    {
        cout << "-1";
        return 0;
    }

    int maxdiff = 0;

    for (int i=0; i<m; i++)
    {
        int curr = cntOst(arrend[i]-arrstart[i],m);
        if (arrend[i]-arrstart[i] < maxdiff)
            maxdiff = arrend[i]-arrstart[i];
        if (ost == -1)
            ost = curr;
        else
        {
            if (ost != curr)
            {
                cout << "-1";
                return 0;
            }
        }
    }

    maxdiff *= -1;

    int N = m - ost;
    while(N == 0 || N < maxdiff)
        N += m;

    for (int i=0; i<m; i++)
    {
        a[i] = (arrend[i] - arrstart[i] + N) / m;
    }

    cout << N << endl;

    for (int i=0; i<N; i++)
    {
        bool minus = true;

        for (int j=0; j<m; j++)
        {
            if (arrstart[j] == 0)
            {
                arrstart[j] += (m-1);
                a[j]--;
                minus = false;
                cout << (j+1) << " ";
            }
            else
            {
                arrstart[j]--;
            }
        }

        if (minus)
        {
            int w=0;
            while (a[w] == 0 && assert(a[w] >= 0))
                w++;
            a[w]--;
            arrstart[w] += m;
            cout << w+1 << " ";
        }

    }

    return 0;
}