#include <bits/stdc++.h>

using namespace std;

const int MAX_N =  400000 + 1;

int A[MAX_N];
long long sum[MAX_N];
int N;

int main()
{
   // freopen("in.txt","r",stdin);
   // freopen("out.txt","w",stdout);
  //  ios_base::sync_with_stdio(false);

    cin >> N;

    for (int i = 1; i <= N; ++i)
    {
        cin >> A[i];
        A[i] %= N;

        sum[i] = (sum[i - 1] + A[i]) % N;

        if (sum[i] == 0)
        {
            cout << i << "\n";

            for (int j = 1; j <= i; ++j)
                cout << j << " ";

            cout << endl;

            return 0;
        }
    }


    }